oneshot

2026-07-04 19:27:17 +09:00
parent 34cd5ad2e7
commit ba6a0b2c17
30 changed files with 2935 additions and 247 deletions
@@ -12,8 +12,8 @@ defmodule Rsh26pool.Application do
      Rsh26pool.Repo,
      {DNSCluster, query: Application.get_env(:rsh26pool, :dns_cluster_query) || :ignore},
      {Phoenix.PubSub, name: Rsh26pool.PubSub},
-      # Start a worker by calling: Rsh26pool.Worker.start_link(arg)
-      # {Rsh26pool.Worker, arg},
+      # Periodically closes rooms that have reached their auto-end time.
+      Rsh26pool.RoomCloser,
      # Start to serve requests, typically the last entry
      Rsh26poolWeb.Endpoint
    ]
@@ -0,0 +1,52 @@
+defmodule Rsh26pool.JST do
+  @moduledoc """
+  Helpers for converting between UTC (how timestamps are stored) and
+  Japan Standard Time (JST, UTC+9) which is what the UI shows and accepts.
+
+  A full time zone database is not configured for this demo, and JST has no
+  daylight saving time, so a fixed +9h offset is sufficient and dependency free.
+  """
+
+  @offset_seconds 9 * 3600
+
+  @doc """
+  Parses a `datetime-local` form value (e.g. `"2026-07-04T15:30"`), interpreting
+  it as wall-clock JST, and returns the corresponding UTC `DateTime`.
+  """
+  @spec parse_local(String.t()) :: {:ok, DateTime.t()} | :error
+  def parse_local(value) when is_binary(value) do
+    with {:ok, naive} <- NaiveDateTime.from_iso8601(ensure_seconds(value)) do
+      utc =
+        naive
+        |> DateTime.from_naive!("Etc/UTC")
+        |> DateTime.add(-@offset_seconds, :second)
+        |> DateTime.truncate(:second)
+
+      {:ok, utc}
+    else
+      _ -> :error
+    end
+  end
+
+  def parse_local(_), do: :error
+
+  @doc "Converts a stored UTC `DateTime` to a JST `DateTime` for display."
+  @spec to_local(DateTime.t()) :: DateTime.t()
+  def to_local(%DateTime{} = dt), do: DateTime.add(dt, @offset_seconds, :second)
+
+  @doc "Formats a stored UTC `DateTime` as a human friendly JST string."
+  @spec format(DateTime.t() | nil) :: String.t()
+  def format(nil), do: ""
+
+  def format(%DateTime{} = dt) do
+    l = to_local(dt)
+
+    "~4..0B/~2..0B/~2..0B ~2..0B:~2..0B"
+    |> :io_lib.format([l.year, l.month, l.day, l.hour, l.minute])
+    |> to_string()
+  end
+
+  defp ensure_seconds(value) do
+    if Regex.match?(~r/T\d{2}:\d{2}$/, value), do: value <> ":00", else: value
+  end
+end
@@ -0,0 +1,45 @@
+defmodule Rsh26pool.RoomCloser do
+  @moduledoc """
+  Periodically closes rooms whose `closes_at` deadline has passed (the "auto
+  end" feature). Closing broadcasts to any connected LiveViews so open pages
+  transition to the results/grouping view without a manual refresh.
+  """
+  use GenServer
+
+  require Logger
+
+  alias Rsh26pool.Voting
+
+  @interval :timer.seconds(10)
+
+  def start_link(opts) do
+    GenServer.start_link(__MODULE__, opts, name: __MODULE__)
+  end
+
+  @impl true
+  def init(_opts) do
+    schedule()
+    {:ok, %{}}
+  end
+
+  @impl true
+  def handle_info(:sweep, state) do
+    sweep()
+    schedule()
+    {:noreply, state}
+  end
+
+  defp sweep do
+    for room <- Voting.list_rooms_to_auto_close() do
+      case Voting.close_room(room) do
+        {:ok, _} ->
+          :ok
+
+        other ->
+          Logger.warning("RoomCloser failed to close room #{room.id}: #{inspect(other)}")
+      end
+    end
+  end
+
+  defp schedule, do: Process.send_after(self(), :sweep, @interval)
+end
@@ -0,0 +1,523 @@
+defmodule Rsh26pool.Voting do
+  @moduledoc """
+  The Voting context: rooms, participants, ideas/opinions, votes, results and
+  (in grouping mode) team assignment via the Hungarian algorithm.
+
+  Timestamps are stored in UTC. Real-time updates are published over
+  `Phoenix.PubSub`; interested LiveViews call `subscribe/1` and handle
+  `{:voting, event}` messages.
+  """
+
+  import Ecto.Query, warn: false
+
+  alias Rsh26pool.Repo
+  alias Rsh26pool.Voting.{Hungarian, Idea, Participant, Room, Vote}
+
+  @pubsub Rsh26pool.PubSub
+
+  ## Real-time -------------------------------------------------------------
+
+  @doc "Subscribe the calling process to a room's update stream."
+  def subscribe(room_id) do
+    Phoenix.PubSub.subscribe(@pubsub, topic(room_id))
+  end
+
+  defp broadcast(room_id, event) do
+    Phoenix.PubSub.broadcast(@pubsub, topic(room_id), {:voting, event})
+  end
+
+  defp topic(room_id), do: "room:#{room_id}"
+
+  ## Rooms ----------------------------------------------------------------
+
+  @doc "Builds a creation changeset for the room settings form."
+  def change_room_creation(%Room{} = room \\ %Room{}, attrs \\ %{}) do
+    Room.create_changeset(room, attrs)
+  end
+
+  @doc "Builds a settings changeset for the manage page rename form."
+  def change_room_settings(%Room{} = room, attrs \\ %{}) do
+    Room.settings_changeset(room, attrs)
+  end
+
+  @doc """
+  Creates a room from the settings form and its owner participant.
+
+  Returns `{:ok, %{room: room, owner: owner}}` or `{:error, changeset}`.
+  """
+  def create_room(attrs) do
+    changeset = Room.create_changeset(%Room{}, attrs)
+
+    if changeset.valid? do
+      changeset = Ecto.Changeset.put_change(changeset, :room_number, unique_room_number())
+
+      Repo.transaction(fn ->
+        room = Repo.insert!(changeset)
+
+        owner =
+          Repo.insert!(%Participant{
+            room_id: room.id,
+            role: "owner",
+            name: "オーナー",
+            token: generate_token()
+          })
+
+        %{room: room, owner: owner}
+      end)
+    else
+      {:error, %{changeset | action: :insert}}
+    end
+  end
+
+  def get_room_by_number(number) when is_binary(number) do
+    Repo.get_by(Room, room_number: number)
+  end
+
+  def get_room_by_number(_), do: nil
+
+  def get_room!(id), do: Repo.get!(Room, id)
+
+  def reload_room(%Room{id: id}), do: Repo.get(Room, id)
+
+  @doc "Updates owner-editable settings (currently the room name)."
+  def update_room_settings(%Room{} = room, attrs) do
+    room
+    |> Room.settings_changeset(attrs)
+    |> Repo.update()
+    |> case do
+      {:ok, room} = ok ->
+        broadcast(room.id, :room_updated)
+        ok
+
+      other ->
+        other
+    end
+  end
+
+  @doc """
+  The status a room should be treated as *right now*, accounting for a passed
+  `closes_at` deadline even if the background closer has not run yet.
+  """
+  def effective_status(%Room{status: "closed"}), do: "closed"
+  def effective_status(%Room{closes_at: nil}), do: "open"
+
+  def effective_status(%Room{closes_at: closes_at}) do
+    if DateTime.compare(closes_at, DateTime.utc_now()) != :gt, do: "closed", else: "open"
+  end
+
+  def room_open?(%Room{} = room), do: effective_status(room) == "open"
+
+  @doc """
+  Closes a room: marks it closed and, in grouping mode, computes the team
+  assignments (idempotent — safe to call more than once).
+  """
+  def close_room(%Room{} = room) do
+    room = Repo.get!(Room, room.id)
+
+    if room.status == "closed" do
+      {:ok, room}
+    else
+      {:ok, closed} =
+        room
+        |> Ecto.Changeset.change(status: "closed")
+        |> Repo.update()
+
+      closed = if closed.grouping_mode, do: compute_grouping(closed), else: closed
+      broadcast(closed.id, :room_updated)
+      {:ok, closed}
+    end
+  end
+
+  @doc """
+  Ensures a room past its deadline is actually closed. Returns the (possibly
+  updated) room. Used lazily by pages so viewers never see a stale open room.
+  """
+  def ensure_closed(%Room{} = room) do
+    if room.status == "open" and effective_status(room) == "closed" do
+      {:ok, closed} = close_room(room)
+      closed
+    else
+      room
+    end
+  end
+
+  @doc "Lists rooms that are open but past their auto-close deadline."
+  def list_rooms_to_auto_close do
+    now = DateTime.utc_now()
+
+    Repo.all(
+      from r in Room,
+        where: r.status == "open" and not is_nil(r.closes_at) and r.closes_at <= ^now
+    )
+  end
+
+  ## Participants ---------------------------------------------------------
+
+  @doc "Changeset for the join form."
+  def change_participant(%Participant{} = participant \\ %Participant{}, attrs \\ %{}) do
+    Participant.changeset(participant, attrs)
+  end
+
+  @doc """
+  Joins a room as a member, generating an auth token.
+
+  Returns `{:ok, participant}` or `{:error, changeset}`.
+  """
+  def join_room(%Room{} = room, attrs) do
+    %Participant{room_id: room.id, role: "member", token: generate_token()}
+    |> Participant.changeset(attrs)
+    |> Repo.insert()
+  end
+
+  def get_participant_by_token(nil), do: nil
+
+  def get_participant_by_token(token) when is_binary(token) do
+    Repo.one(from p in Participant, where: p.token == ^token, preload: [:room])
+  end
+
+  def list_participants(%Room{} = room) do
+    Repo.all(from p in Participant, where: p.room_id == ^room.id, order_by: [asc: p.id])
+  end
+
+  def count_participants(%Room{} = room) do
+    Repo.aggregate(from(p in Participant, where: p.room_id == ^room.id), :count)
+  end
+
+  ## Ideas ----------------------------------------------------------------
+
+  def change_idea(%Idea{} = idea \\ %Idea{}, attrs \\ %{}) do
+    Idea.changeset(idea, attrs)
+  end
+
+  @doc """
+  Posts an idea/opinion. In grouping mode each participant has a single opinion,
+  so an existing one is updated instead of inserting a second.
+  """
+  def create_idea(%Room{} = room, %Participant{} = participant, attrs) do
+    cond do
+      not room_open?(room) ->
+        {:error, :closed}
+
+      room.grouping_mode ->
+        case get_participant_idea(room, participant) do
+          nil -> do_insert_idea(room, participant, attrs)
+          existing -> do_update_idea(room, existing, attrs)
+        end
+
+      true ->
+        do_insert_idea(room, participant, attrs)
+    end
+  end
+
+  defp do_insert_idea(room, participant, attrs) do
+    %Idea{room_id: room.id, participant_id: participant.id}
+    |> Idea.changeset(attrs)
+    |> Repo.insert()
+    |> tap_broadcast(room, :ideas_changed)
+  end
+
+  defp do_update_idea(room, idea, attrs) do
+    idea
+    |> Idea.changeset(attrs)
+    |> Repo.update()
+    |> tap_broadcast(room, :ideas_changed)
+  end
+
+  def get_participant_idea(%Room{} = room, %Participant{} = participant) do
+    Repo.one(
+      from i in Idea,
+        where: i.room_id == ^room.id and i.participant_id == ^participant.id,
+        order_by: [asc: i.id],
+        limit: 1
+    )
+  end
+
+  def list_ideas(%Room{} = room) do
+    Repo.all(
+      from i in Idea,
+        where: i.room_id == ^room.id,
+        order_by: [asc: i.id],
+        preload: [:participant]
+    )
+  end
+
+  @doc """
+  Ideas ordered by a per-viewer deterministic shuffle. Order is stable for a
+  given `seed` (so it does not jump around on live updates) but differs between
+  viewers, satisfying the "shuffled choices" requirement.
+  """
+  def shuffled_ideas(%Room{} = room, seed) do
+    room
+    |> list_ideas()
+    |> Enum.sort_by(fn idea -> :erlang.phash2({seed, idea.id}) end)
+  end
+
+  ## Votes ----------------------------------------------------------------
+
+  @doc """
+  Casts a vote for `idea_id` by `participant`, enforcing the room's per-user
+  vote limit, one-vote-per-idea, and that the room is still open.
+  """
+  def vote(%Participant{} = participant, idea_id) do
+    room = Repo.get!(Room, participant.room_id)
+    idea = Repo.get_by(Idea, id: idea_id, room_id: room.id)
+
+    cond do
+      not room_open?(room) -> {:error, :closed}
+      is_nil(idea) -> {:error, :not_found}
+      voted?(participant, idea.id) -> {:error, :already_voted}
+      votes_used(participant) >= room.votes_per_user -> {:error, :limit_reached}
+      true -> insert_vote(room, participant, idea)
+    end
+  end
+
+  defp insert_vote(room, participant, idea) do
+    %Vote{}
+    |> Vote.changeset(%{idea_id: idea.id, participant_id: participant.id})
+    |> Repo.insert()
+    |> case do
+      {:ok, vote} ->
+        broadcast(room.id, :votes_changed)
+        {:ok, vote}
+
+      {:error, changeset} ->
+        {:error, changeset}
+    end
+  end
+
+  @doc "Removes a participant's vote for an idea, if the room is still open."
+  def unvote(%Participant{} = participant, idea_id) do
+    room = Repo.get!(Room, participant.room_id)
+
+    cond do
+      not room_open?(room) ->
+        {:error, :closed}
+
+      true ->
+        case Repo.get_by(Vote, idea_id: idea_id, participant_id: participant.id) do
+          nil ->
+            {:error, :not_found}
+
+          vote ->
+            {:ok, _} = Repo.delete(vote)
+            broadcast(room.id, :votes_changed)
+            :ok
+        end
+    end
+  end
+
+  def voted?(%Participant{} = participant, idea_id) do
+    Repo.exists?(
+      from v in Vote, where: v.participant_id == ^participant.id and v.idea_id == ^idea_id
+    )
+  end
+
+  def votes_used(%Participant{} = participant) do
+    Repo.aggregate(from(v in Vote, where: v.participant_id == ^participant.id), :count)
+  end
+
+  def votes_remaining(%Room{} = room, %Participant{} = participant) do
+    max(room.votes_per_user - votes_used(participant), 0)
+  end
+
+  @doc "Set of idea ids the participant has voted for (for UI highlighting)."
+  def voted_idea_ids(%Participant{} = participant) do
+    Repo.all(from v in Vote, where: v.participant_id == ^participant.id, select: v.idea_id)
+    |> MapSet.new()
+  end
+
+  ## Results --------------------------------------------------------------
+
+  @doc "Map of `idea_id => vote_count` for a room."
+  def vote_counts(%Room{} = room) do
+    Repo.all(
+      from v in Vote,
+        join: i in Idea,
+        on: i.id == v.idea_id,
+        where: i.room_id == ^room.id,
+        group_by: v.idea_id,
+        select: {v.idea_id, count(v.id)}
+    )
+    |> Map.new()
+  end
+
+  @doc "Ideas with their vote counts, highest first (for the manage page)."
+  def results(%Room{} = room) do
+    counts = vote_counts(room)
+
+    room
+    |> list_ideas()
+    |> Enum.map(fn idea -> %{idea: idea, count: Map.get(counts, idea.id, 0)} end)
+    |> Enum.sort_by(& &1.count, :desc)
+  end
+
+  ## Grouping mode --------------------------------------------------------
+
+  @doc """
+  Returns the computed grouping as `%{groups: [...], ungrouped: [...]}` where
+  each group is `%{leader: participant, opinion: idea, members: [participant]}`.
+  Only meaningful after a grouping-mode room has been closed.
+  """
+  def group_assignments(%Room{} = room) do
+    members = room |> list_participants() |> Enum.filter(&(&1.role == "member"))
+    counts = vote_counts(room)
+    idea_by_participant = idea_by_participant(room)
+
+    leaders =
+      members
+      |> Enum.filter(& &1.is_leader)
+      |> Enum.sort_by(&(-opinion_votes(&1, idea_by_participant, counts)))
+
+    groups =
+      Enum.map(leaders, fn leader ->
+        group_members =
+          Enum.filter(members, fn p ->
+            not p.is_leader and p.assigned_leader_id == leader.id
+          end)
+
+        %{
+          leader: leader,
+          opinion: Map.get(idea_by_participant, leader.id),
+          members: group_members
+        }
+      end)
+
+    ungrouped =
+      Enum.filter(members, fn p -> not p.is_leader and is_nil(p.assigned_leader_id) end)
+
+    %{groups: groups, ungrouped: ungrouped}
+  end
+
+  defp compute_grouping(room) do
+    members = room |> list_participants() |> Enum.filter(&(&1.role == "member"))
+    counts = vote_counts(room)
+    idea_by_participant = idea_by_participant(room)
+
+    leaders =
+      Enum.filter(members, fn p ->
+        Map.has_key?(idea_by_participant, p.id) and
+          opinion_votes(p, idea_by_participant, counts) >= room.leader_threshold
+      end)
+
+    regular = members -- leaders
+
+    Repo.transaction(fn ->
+      if leaders == [] do
+        Enum.each(members, &set_group(&1, false, nil))
+      else
+        Enum.each(leaders, &set_group(&1, true, &1.id))
+
+        regular
+        |> assign_regular_members(leaders, room, idea_by_participant)
+        |> Enum.each(fn {member, leader_id} -> set_group(member, false, leader_id) end)
+      end
+
+      now = DateTime.utc_now() |> DateTime.truncate(:second)
+      Repo.update!(Ecto.Changeset.change(room, grouped_at: now))
+    end)
+    |> case do
+      {:ok, updated_room} -> updated_room
+    end
+  end
+
+  # Assigns non-leader members to leader groups minimising unmet preferences via
+  # the Hungarian algorithm. Returns `[{member, leader_id}]`.
+  defp assign_regular_members([], _leaders, _room, _idea_by_participant), do: []
+
+  defp assign_regular_members(regular, leaders, room, idea_by_participant) do
+    m = length(regular)
+    l = length(leaders)
+    base = div(m, l)
+    remainder = rem(m, l)
+
+    # Balanced capacity per leader; expanded into one slot per capacity unit.
+    caps = Enum.map(0..(l - 1), fn i -> base + if(i < remainder, do: 1, else: 0) end)
+
+    slot_leaders =
+      Enum.flat_map(Enum.zip(leaders, caps), fn {leader, cap} ->
+        List.duplicate(leader, cap)
+      end)
+
+    voted_by = votes_by_participant(room)
+
+    cost =
+      Enum.map(regular, fn member ->
+        voted = Map.get(voted_by, member.id, MapSet.new())
+
+        Enum.map(slot_leaders, fn leader ->
+          opinion = Map.get(idea_by_participant, leader.id)
+
+          if opinion && MapSet.member?(voted, opinion.id), do: 0, else: 1
+        end)
+      end)
+
+    {_total, assignment} = Hungarian.min_cost_assignment(cost)
+
+    regular
+    |> Enum.zip(assignment)
+    |> Enum.map(fn {member, slot_index} ->
+      leader = Enum.at(slot_leaders, slot_index)
+      {member, leader.id}
+    end)
+  end
+
+  defp set_group(participant, is_leader, leader_id) do
+    participant
+    |> Ecto.Changeset.change(is_leader: is_leader, assigned_leader_id: leader_id)
+    |> Repo.update!()
+  end
+
+  defp idea_by_participant(room) do
+    room
+    |> list_ideas()
+    |> Map.new(fn idea -> {idea.participant_id, idea} end)
+  end
+
+  defp opinion_votes(participant, idea_by_participant, counts) do
+    case Map.get(idea_by_participant, participant.id) do
+      nil -> 0
+      idea -> Map.get(counts, idea.id, 0)
+    end
+  end
+
+  defp votes_by_participant(room) do
+    Repo.all(
+      from v in Vote,
+        join: i in Idea,
+        on: i.id == v.idea_id,
+        where: i.room_id == ^room.id,
+        select: {v.participant_id, v.idea_id}
+    )
+    |> Enum.group_by(&elem(&1, 0), &elem(&1, 1))
+    |> Map.new(fn {participant_id, idea_ids} -> {participant_id, MapSet.new(idea_ids)} end)
+  end
+
+  ## Helpers --------------------------------------------------------------
+
+  defp generate_token do
+    :crypto.strong_rand_bytes(24) |> Base.url_encode64(padding: false)
+  end
+
+  defp unique_room_number(attempts \\ 0)
+
+  defp unique_room_number(attempts) when attempts < 20 do
+    number = Integer.to_string(:rand.uniform(900_000) + 99_999)
+
+    if Repo.exists?(from r in Room, where: r.room_number == ^number) do
+      unique_room_number(attempts + 1)
+    else
+      number
+    end
+  end
+
+  defp unique_room_number(_attempts) do
+    raise "could not allocate a unique room number"
+  end
+
+  defp tap_broadcast({:ok, _} = result, room, event) do
+    broadcast(room.id, event)
+    result
+  end
+
+  defp tap_broadcast(other, _room, _event), do: other
+end
@@ -0,0 +1,114 @@
+defmodule Rsh26pool.Voting.Hungarian do
+  @moduledoc """
+  Solves the assignment problem — a minimum-cost perfect matching in a weighted
+  bipartite graph — with the Hungarian (Kuhn–Munkres) algorithm in O(n^3).
+
+  This is the algorithm the proposal calls for when placing members into groups
+  in grouping mode: given a cost of assigning each member to each group slot, it
+  finds the assignment with the lowest total cost.
+
+  `min_cost_assignment/1` takes an `n x m` cost matrix (a list of `n` rows, each
+  a list of `m` numbers) with `n <= m`, and returns `{total_cost, assignment}`
+  where `assignment` is a list of length `n` and `Enum.at(assignment, i)` is the
+  0-based column matched to row `i`.
+  """
+
+  @inf 1_000_000_000
+
+  @spec min_cost_assignment([[number()]]) :: {number(), [non_neg_integer()]}
+  def min_cost_assignment([]), do: {0, []}
+
+  def min_cost_assignment(cost) when is_list(cost) do
+    n = length(cost)
+    m = length(hd(cost))
+
+    if n > m do
+      raise ArgumentError, "cost matrix must have rows <= cols (got #{n} x #{m})"
+    end
+
+    # 1-indexed access into an immutable tuple-of-tuples.
+    c = cost |> Enum.map(&List.to_tuple/1) |> List.to_tuple()
+    cost_at = fn i, j -> c |> elem(i - 1) |> elem(j - 1) end
+
+    u = fill(n + 1, 0)
+    v = fill(m + 1, 0)
+    p = fill(m + 1, 0)
+    way = fill(m + 1, 0)
+
+    {_u, _v, p, _way} =
+      Enum.reduce(1..n, {u, v, p, way}, fn i, {u, v, p, way} ->
+        phase(i, m, cost_at, u, v, p, way)
+      end)
+
+    # p[j] holds the row matched to column j; invert to get column-per-row.
+    row_to_col =
+      Enum.reduce(1..m, %{}, fn j, acc ->
+        row = elem(p, j)
+        if row >= 1 and row <= n, do: Map.put(acc, row, j - 1), else: acc
+      end)
+
+    assignment = Enum.map(1..n, &Map.fetch!(row_to_col, &1))
+
+    total =
+      assignment
+      |> Enum.with_index(1)
+      |> Enum.reduce(0, fn {col0, i}, sum -> sum + cost_at.(i, col0 + 1) end)
+
+    {total, assignment}
+  end
+
+  # Augmenting phase for row `i` (see the classic e-maxx Hungarian description).
+  defp phase(i, m, cost_at, u, v, p, way) do
+    p = put_elem(p, 0, i)
+    minv = fill(m + 1, @inf)
+    used = fill(m + 1, false)
+    walk(0, m, cost_at, u, v, p, way, minv, used)
+  end
+
+  defp walk(j0, m, cost_at, u, v, p, way, minv, used) do
+    used = put_elem(used, j0, true)
+    i0 = elem(p, j0)
+    ui0 = elem(u, i0)
+
+    {delta, j1, minv, way} =
+      Enum.reduce(1..m, {@inf, -1, minv, way}, fn j, {delta, j1, minv, way} ->
+        if elem(used, j) do
+          {delta, j1, minv, way}
+        else
+          cur = cost_at.(i0, j) - ui0 - elem(v, j)
+
+          {minv, way} =
+            if cur < elem(minv, j),
+              do: {put_elem(minv, j, cur), put_elem(way, j, j0)},
+              else: {minv, way}
+
+          mvj = elem(minv, j)
+          if mvj < delta, do: {mvj, j, minv, way}, else: {delta, j1, minv, way}
+        end
+      end)
+
+    {u, v, minv} =
+      Enum.reduce(0..m, {u, v, minv}, fn j, {u, v, minv} ->
+        if elem(used, j) do
+          pj = elem(p, j)
+          {put_elem(u, pj, elem(u, pj) + delta), put_elem(v, j, elem(v, j) - delta), minv}
+        else
+          {u, v, put_elem(minv, j, elem(minv, j) - delta)}
+        end
+      end)
+
+    if elem(p, j1) == 0 do
+      {u, v, reconstruct(j1, p, way), way}
+    else
+      walk(j1, m, cost_at, u, v, p, way, minv, used)
+    end
+  end
+
+  defp reconstruct(j0, p, way) do
+    j1 = elem(way, j0)
+    p = put_elem(p, j0, elem(p, j1))
+    if j1 == 0, do: p, else: reconstruct(j1, p, way)
+  end
+
+  defp fill(size, value), do: value |> List.duplicate(size) |> List.to_tuple()
+end
@@ -0,0 +1,27 @@
+defmodule Rsh26pool.Voting.Idea do
+  @moduledoc """
+  A voting option. In normal mode it is an idea posted by a participant; in
+  grouping mode it is the participant's opinion (one per participant).
+  """
+  use Ecto.Schema
+  import Ecto.Changeset
+
+  alias Rsh26pool.Voting.{Participant, Room, Vote}
+
+  schema "ideas" do
+    field :text, :string
+
+    belongs_to :room, Room
+    belongs_to :participant, Participant
+    has_many :votes, Vote
+
+    timestamps(type: :utc_datetime)
+  end
+
+  def changeset(idea, attrs) do
+    idea
+    |> cast(attrs, [:text])
+    |> validate_required([:text], message: "内容を入力してください")
+    |> validate_length(:text, max: 200, message: "200文字以内で入力してください")
+  end
+end
@@ -0,0 +1,37 @@
+defmodule Rsh26pool.Voting.Participant do
+  @moduledoc """
+  A user taking part in a room. Identified across requests by a random `token`
+  stored in the session cookie. Owners have `role == "owner"`.
+  """
+  use Ecto.Schema
+  import Ecto.Changeset
+
+  alias Rsh26pool.Voting.Room
+
+  schema "participants" do
+    field :token, :string
+    field :name, :string
+    field :role, :string, default: "member"
+
+    # Grouping-mode results, filled in when voting closes.
+    field :is_leader, :boolean, default: false
+
+    belongs_to :room, Room
+    belongs_to :assigned_leader, __MODULE__, foreign_key: :assigned_leader_id
+
+    timestamps(type: :utc_datetime)
+  end
+
+  @doc "Changeset for the user-supplied fields (their display name)."
+  def changeset(participant, attrs) do
+    participant
+    |> cast(attrs, [:name])
+    |> validate_required([:name], message: "名前を入力してください")
+    |> validate_length(:name, max: 40, message: "名前は40文字以内で入力してください")
+    |> unique_constraint(:token)
+  end
+
+  @doc "Owner? convenience predicate."
+  def owner?(%__MODULE__{role: "owner"}), do: true
+  def owner?(%__MODULE__{}), do: false
+end
@@ -0,0 +1,81 @@
+defmodule Rsh26pool.Voting.Room do
+  @moduledoc """
+  A voting room. Identified publicly by a short `room_number` used in URLs.
+  """
+  use Ecto.Schema
+  import Ecto.Changeset
+
+  alias Rsh26pool.Voting.{Idea, Participant}
+
+  schema "rooms" do
+    field :room_number, :string
+    field :name, :string
+    field :votes_per_user, :integer, default: 3
+    field :status, :string, default: "open"
+    field :grouping_mode, :boolean, default: false
+    field :leader_threshold, :integer, default: 2
+    field :closes_at, :utc_datetime
+    field :grouped_at, :utc_datetime
+
+    # Virtual field backing the `datetime-local` input (wall-clock JST).
+    field :closes_at_local, :string, virtual: true
+
+    has_many :participants, Participant
+    has_many :ideas, Idea
+
+    timestamps(type: :utc_datetime)
+  end
+
+  @doc "Changeset used when the owner creates a new room."
+  def create_changeset(room, attrs) do
+    room
+    |> cast(attrs, [
+      :name,
+      :votes_per_user,
+      :grouping_mode,
+      :leader_threshold,
+      :closes_at_local
+    ])
+    |> validate_required([:name, :votes_per_user], message: "入力してください")
+    |> validate_length(:name, max: 80, message: "80文字以内で入力してください")
+    |> validate_number(:votes_per_user,
+      greater_than_or_equal_to: 1,
+      less_than_or_equal_to: 50,
+      message: "1〜50の数値を入力してください"
+    )
+    |> validate_number(:leader_threshold,
+      greater_than_or_equal_to: 1,
+      less_than_or_equal_to: 50,
+      message: "1〜50の数値を入力してください"
+    )
+    |> put_closes_at()
+  end
+
+  @doc "Changeset for owner-editable settings on the manage page."
+  def settings_changeset(room, attrs) do
+    room
+    |> cast(attrs, [:name])
+    |> validate_required([:name], message: "入力してください")
+    |> validate_length(:name, max: 80, message: "80文字以内で入力してください")
+  end
+
+  defp put_closes_at(changeset) do
+    case get_field(changeset, :closes_at_local) do
+      blank when blank in [nil, ""] ->
+        put_change(changeset, :closes_at, nil)
+
+      value ->
+        case Rsh26pool.JST.parse_local(value) do
+          {:ok, dt} ->
+            if DateTime.compare(dt, DateTime.utc_now()) == :gt do
+              put_change(changeset, :closes_at, dt)
+            else
+              add_error(changeset, :closes_at_local, "未来の日時を指定してください")
+            end
+
+          :error ->
+            add_error(changeset, :closes_at_local, "日時の形式が正しくありません")
+        end
+    end
+  end
+end
@@ -0,0 +1,29 @@
+defmodule Rsh26pool.Voting.Vote do
+  @moduledoc """
+  A single vote cast by a participant for an idea. A participant may vote for a
+  given idea at most once (enforced by a unique index).
+  """
+  use Ecto.Schema
+  import Ecto.Changeset
+
+  alias Rsh26pool.Voting.{Idea, Participant}
+
+  schema "votes" do
+    belongs_to :idea, Idea
+    belongs_to :participant, Participant
+
+    timestamps(type: :utc_datetime)
+  end
+
+  def changeset(vote, attrs) do
+    vote
+    |> cast(attrs, [:idea_id, :participant_id])
+    |> validate_required([:idea_id, :participant_id])
+    |> unique_constraint([:idea_id, :participant_id],
+      name: :votes_idea_id_participant_id_index,
+      message: "は既に投票済みです"
+    )
+    |> foreign_key_constraint(:idea_id)
+    |> foreign_key_constraint(:participant_id)
+  end
+end
@@ -0,0 +1,99 @@
+defmodule Rsh26poolWeb.Auth do
+  @moduledoc """
+  Token-based authentication.
+
+  When a user creates or joins a room we generate a random token, persist it on
+  their `Participant` row, and store that token in the session cookie. On every
+  request the token is looked up to identify the current participant. This is
+  the token scheme described in the proposal (a random string whose owner is
+  recorded in the database, kept in a cookie).
+  """
+  use Rsh26poolWeb, :verified_routes
+
+  import Plug.Conn
+
+  alias Phoenix.LiveView
+  alias Rsh26pool.Voting
+
+  @token_key "participant_token"
+
+  ## Plug (controllers) ---------------------------------------------------
+
+  @doc "Assigns `:current_participant` from the session token (may be nil)."
+  def fetch_current_participant(conn, _opts) do
+    participant = participant_from_token(get_session(conn, @token_key))
+    assign(conn, :current_participant, participant)
+  end
+
+  @doc "Persists a participant's token in the session and assigns it."
+  def log_in_participant(conn, participant) do
+    conn
+    |> put_session(@token_key, participant.token)
+    |> assign(:current_participant, participant)
+  end
+
+  @doc "Clears the session token (logout)."
+  def log_out_participant(conn) do
+    conn
+    |> delete_session(@token_key)
+    |> assign(:current_participant, nil)
+  end
+
+  ## LiveView on_mount hooks ---------------------------------------------
+
+  @doc """
+  `on_mount` hooks:
+
+    * `:mount_current_participant` — assigns `:current_participant` (may be nil)
+    * `:require_participant` — requires the viewer to belong to the room in the
+      URL, otherwise redirects to the enter page
+    * `:require_owner` — requires the viewer to be the owner of the room
+  """
+  def on_mount(:mount_current_participant, _params, session, socket) do
+    {:cont, assign_current_participant(socket, session)}
+  end
+
+  def on_mount(:require_participant, params, session, socket) do
+    socket = assign_current_participant(socket, session)
+    participant = socket.assigns.current_participant
+    room_number = params["room_number"]
+
+    if participant && participant.room && participant.room.room_number == room_number do
+      {:cont, socket}
+    else
+      socket =
+        socket
+        |> LiveView.put_flash(:error, "このルームに参加するには入室してください。")
+        |> LiveView.redirect(to: ~p"/enter?#{[room: room_number]}")
+
+      {:halt, socket}
+    end
+  end
+
+  def on_mount(:require_owner, params, session, socket) do
+    socket = assign_current_participant(socket, session)
+    participant = socket.assigns.current_participant
+    room_number = params["room_number"]
+
+    if participant && participant.room && participant.room.room_number == room_number &&
+         participant.role == "owner" do
+      {:cont, socket}
+    else
+      socket =
+        socket
+        |> LiveView.put_flash(:error, "この管理ページにアクセスする権限がありません。")
+        |> LiveView.redirect(to: ~p"/")
+
+      {:halt, socket}
+    end
+  end
+
+  defp assign_current_participant(socket, session) do
+    Phoenix.Component.assign_new(socket, :current_participant, fn ->
+      participant_from_token(session[@token_key])
+    end)
+  end
+
+  defp participant_from_token(nil), do: nil
+  defp participant_from_token(token), do: Voting.get_participant_by_token(token)
+end
@@ -27,43 +27,39 @@ defmodule Rsh26poolWeb.Layouts do
  """
  attr :flash, :map, required: true, doc: "the map of flash messages"

-  attr :current_scope, :map,
+  attr :current_participant, :map,
    default: nil,
-    doc: "the current [scope](https://phoenix.hexdocs.pm/scopes.html)"
+    doc: "the currently logged-in participant, if any"

  slot :inner_block, required: true

  def app(assigns) do
    ~H"""
-    <header class="navbar px-4 sm:px-6 lg:px-8">
+    <header class="navbar bg-base-100 border-b border-base-200 px-4 sm:px-6 lg:px-8">
      <div class="flex-1">
-        <a href="/" class="flex-1 flex w-fit items-center gap-2">
-          <img src={~p"/images/logo.svg"} width="36" />
-          <span class="text-sm font-semibold">v{Application.spec(:phoenix, :vsn)}</span>
-        </a>
+        <.link navigate={~p"/"} class="flex items-center gap-2 text-lg font-bold">
+          <.icon name="hero-check-badge" class="size-7 text-primary" />
+          <span>みんなで投票</span>
+        </.link>
      </div>
-      <div class="flex-none">
-        <ul class="flex flex-column px-1 space-x-4 items-center">
-          <li>
-            <a href="https://phoenixframework.org/" class="btn btn-ghost">Website</a>
-          </li>
-          <li>
-            <a href="https://github.com/phoenixframework/phoenix" class="btn btn-ghost">GitHub</a>
-          </li>
-          <li>
-            <.theme_toggle />
-          </li>
-          <li>
-            <a href="https://phoenix.hexdocs.pm/overview.html" class="btn btn-primary">
-              Get Started <span aria-hidden="true">&rarr;</span>
-            </a>
-          </li>
-        </ul>
+      <div class="flex-none flex items-center gap-3">
+        <.theme_toggle />
+        <div :if={@current_participant} class="flex items-center gap-2">
+          <span class="hidden sm:inline text-sm text-base-content/70">
+            {@current_participant.name} さん
+          </span>
+          <.form for={%{}} action={~p"/logout"} method="delete">
+            <button class="btn btn-sm btn-ghost gap-1" type="submit">
+              <.icon name="hero-arrow-right-on-rectangle" class="size-4" />
+              <span class="hidden sm:inline">ログアウト</span>
+            </button>
+          </.form>
+        </div>
      </div>
    </header>

-    <main class="px-4 py-20 sm:px-6 lg:px-8">
-      <div class="mx-auto max-w-2xl space-y-4">
+    <main class="px-4 py-10 sm:px-6 lg:px-8">
+      <div class="mx-auto max-w-3xl space-y-6">
        {render_slot(@inner_block)}
      </div>
    </main>
@@ -91,7 +87,7 @@ defmodule Rsh26poolWeb.Layouts do
      <.flash
        id="client-error"
        kind={:error}
-        title={gettext("We can't find the internet")}
+        title="インターネットに接続できません"
        phx-disconnected={
          show(".phx-client-error #client-error")
          |> JS.remove_attribute("hidden", to: ".phx-client-error #client-error")
@@ -99,14 +95,13 @@ defmodule Rsh26poolWeb.Layouts do
        phx-connected={hide("#client-error") |> JS.set_attribute({"hidden", ""})}
        hidden
      >
-        {gettext("Attempting to reconnect")}
-        <.icon name="hero-arrow-path" class="ml-1 size-3 motion-safe:animate-spin" />
+        再接続を試みています <.icon name="hero-arrow-path" class="ml-1 size-3 motion-safe:animate-spin" />
      </.flash>

      <.flash
        id="server-error"
        kind={:error}
-        title={gettext("Something went wrong!")}
+        title="問題が発生しました"
        phx-disconnected={
          show(".phx-server-error #server-error")
          |> JS.remove_attribute("hidden", to: ".phx-server-error #server-error")
@@ -114,8 +109,7 @@ defmodule Rsh26poolWeb.Layouts do
        phx-connected={hide("#server-error") |> JS.set_attribute({"hidden", ""})}
        hidden
      >
-        {gettext("Attempting to reconnect")}
-        <.icon name="hero-arrow-path" class="ml-1 size-3 motion-safe:animate-spin" />
+        再接続を試みています <.icon name="hero-arrow-path" class="ml-1 size-3 motion-safe:animate-spin" />
      </.flash>
    </div>
    """
@@ -1,10 +1,10 @@
 <!DOCTYPE html>
-<html lang="en">
+<html lang="ja">
  <head>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1" />
    <meta name="csrf-token" content={get_csrf_token()} />
-    <.live_title default="Rsh26pool" suffix=" · Phoenix Framework" phx-no-format>{assigns[:page_title]}</.live_title>
+    <.live_title default="みんなで投票" suffix=" · 投票アプリ" phx-no-format>{assigns[:page_title]}</.live_title>
    <link phx-track-static rel="stylesheet" href={~p"/assets/css/app.css"} />
    <script defer phx-track-static type="text/javascript" src={~p"/assets/js/app.js"}>
    </script>
@@ -1,199 +1,67 @@
-<Layouts.flash_group flash={@flash} />
-<div class="left-[40rem] fixed inset-y-0 right-0 z-0 hidden lg:block xl:left-[50rem]">
-  <svg
-    viewBox="0 0 1480 957"
-    fill="none"
-    aria-hidden="true"
-    class="absolute inset-0 h-full w-full"
-    preserveAspectRatio="xMinYMid slice"
-  >
-    <path fill="#EE7868" d="M0 0h1480v957H0z" />
-    <path
-      d="M137.542 466.27c-582.851-48.41-988.806-82.127-1608.412 658.2l67.39 810 3083.15-256.51L1535.94-49.622l-98.36 8.183C1269.29 281.468 734.115 515.799 146.47 467.012l-8.928-.742Z"
-      fill="#FF9F92"
-    />
-    <path
-      d="M371.028 528.664C-169.369 304.988-545.754 149.198-1361.45 665.565l-182.58 792.025 3014.73 694.98 389.42-1689.25-96.18-22.171C1505.28 697.438 924.153 757.586 379.305 532.09l-8.277-3.426Z"
-      fill="#FA8372"
-    />
-    <path
-      d="M359.326 571.714C-104.765 215.795-428.003-32.102-1349.55 255.554l-282.3 1224.596 3047.04 722.01 312.24-1354.467C1411.25 1028.3 834.355 935.995 366.435 577.166l-7.109-5.452Z"
-      fill="#E96856"
-      fill-opacity=".6"
-    />
-    <path
-      d="M1593.87 1236.88c-352.15 92.63-885.498-145.85-1244.602-613.557l-5.455-7.105C-12.347 152.31-260.41-170.8-1225-131.458l-368.63 1599.048 3057.19 704.76 130.31-935.47Z"
-      fill="#C42652"
-      fill-opacity=".2"
-    />
-    <path
-      d="M1411.91 1526.93c-363.79 15.71-834.312-330.6-1085.883-863.909l-3.822-8.102C72.704 125.95-101.074-242.476-1052.01-408.907l-699.85 1484.267 2837.75 1338.01 326.02-886.44Z"
-      fill="#A41C42"
-      fill-opacity=".2"
-    />
-    <path
-      d="M1116.26 1863.69c-355.457-78.98-720.318-535.27-825.287-1115.521l-1.594-8.816C185.286 163.833 112.786-237.016-762.678-643.898L-1822.83 608.665 571.922 2635.55l544.338-771.86Z"
-      fill="#A41C42"
-      fill-opacity=".2"
-    />
-  </svg>
-</div>
-<div class="px-4 py-10 sm:px-6 sm:py-28 lg:px-8 xl:px-28 xl:py-32">
-  <div class="mx-auto max-w-xl lg:mx-0">
-    <svg viewBox="0 0 71 48" class="h-12" aria-hidden="true">
-      <path
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-        fill="#FD4F00"
-      />
-    </svg>
-    <div class="mt-10 flex justify-between items-center">
-      <h1 class="flex items-center text-sm font-semibold leading-6">
-        Phoenix Framework
-        <small class="badge badge-warning badge-sm ml-3">
-          v{Application.spec(:phoenix, :vsn)}
-        </small>
-      </h1>
-      <Layouts.theme_toggle />
-    </div>
-
-    <p class="text-[2rem] mt-4 font-semibold leading-10 tracking-tighter text-balance">
-      Peace of mind from prototype to production.
+<Layouts.app flash={@flash} current_participant={@current_participant}>
+  <div class="text-center py-6">
+    <h1 class="text-4xl sm:text-5xl font-extrabold tracking-tight">
+      みんなで<span class="text-primary">投票</span>
+    </h1>
+    <p class="mt-4 text-base-content/70">
+      ルームを作って、アイデアを出し合い、好きなものに投票しよう。
    </p>
-    <p class="mt-4 leading-7 text-base-content/70">
-      Build rich, interactive web applications quickly, with less code and fewer moving parts. Join our growing community of developers using Phoenix to craft APIs, HTML5 apps and more, for fun or at scale.
-    </p>
-    <div class="flex">
-      <div class="w-full sm:w-auto">
-        <div class="mt-10 grid grid-cols-1 gap-x-6 gap-y-4 sm:grid-cols-3">
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-            href="https://phoenix.hexdocs.pm/overview.html"
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-          >
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-              </svg>
-              Guides &amp; Docs
-            </span>
-          </a>
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-                  fill="currentColor"
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-                />
-              </svg>
-              Source Code
-            </span>
-          </a>
-          <a
-            href={"https://github.com/phoenixframework/phoenix/blob/v#{Application.spec(:phoenix, :vsn)}/CHANGELOG.md"}
-            class="group relative rounded-box px-6 py-4 text-sm font-semibold leading-6 sm:py-6"
-          >
-            <span class="absolute inset-0 rounded-box bg-base-200 transition group-hover:bg-base-300 sm:group-hover:scale-105"></span>
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-                  d="M12 1v6M12 17v6"
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-                />
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-                  cx="12"
-                  cy="12"
-                  r="4"
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-                  stroke-width="2"
-                  stroke-linecap="round"
-                  stroke-linejoin="round"
-                />
-              </svg>
-              Changelog
-            </span>
-          </a>
-        </div>
-        <div class="mt-10 grid grid-cols-1 gap-y-4 text-sm leading-6 text-base-content/80 sm:grid-cols-2">
-          <div>
-            <a
-              href="https://elixirforum.com"
-              class="group -mx-2 -my-0.5 inline-flex items-center gap-3 rounded-lg px-2 py-0.5 hover:bg-base-200 hover:text-base-content"
-            >
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-              >
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-              </svg>
-              Discuss on the Elixir Forum
-            </a>
-          </div>
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-            <a
-              href="https://discord.gg/elixir"
-              class="group -mx-2 -my-0.5 inline-flex items-center gap-3 rounded-lg px-2 py-0.5 hover:bg-base-200 hover:text-base-content"
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-              </svg>
-              Deploy your application
-            </a>
-          </div>
-        </div>
-      </div>
-    </div>
  </div>
-</div>
+
+  <div
+    :if={@current_participant}
+    class="alert bg-base-200 border border-base-300 flex items-center justify-between"
+  >
+    <span>
+      現在ルーム「{@current_participant.room.name}」（番号 {@current_participant.room.room_number}）に参加中です。
+    </span>
+    <.link
+      :if={@current_participant.role == "owner"}
+      navigate={~p"/manage/#{@current_participant.room.room_number}"}
+      class="btn btn-sm btn-primary"
+    >
+      管理ページへ
+    </.link>
+    <.link
+      :if={@current_participant.role != "owner"}
+      navigate={~p"/vote/#{@current_participant.room.room_number}"}
+      class="btn btn-sm btn-primary"
+    >
+      投票ページへ
+    </.link>
+  </div>
+
+  <div class="grid gap-4 sm:grid-cols-2 mt-4">
+    <.link
+      navigate={~p"/create"}
+      id="home-create-link"
+      class="card bg-base-100 border border-base-200 shadow-sm hover:shadow-md hover:border-primary transition group"
+    >
+      <div class="card-body items-center text-center">
+        <div class="rounded-full bg-primary/10 p-4 group-hover:bg-primary/20 transition">
+          <.icon name="hero-plus-circle" class="size-8 text-primary" />
+        </div>
+        <h2 class="card-title mt-2">ルームを作成</h2>
+        <p class="text-sm text-base-content/70">
+          投票の設定を決めて、新しいルームを立ち上げます。
+        </p>
+      </div>
+    </.link>
+
+    <.link
+      navigate={~p"/enter"}
+      id="home-enter-link"
+      class="card bg-base-100 border border-base-200 shadow-sm hover:shadow-md hover:border-primary transition group"
+    >
+      <div class="card-body items-center text-center">
+        <div class="rounded-full bg-primary/10 p-4 group-hover:bg-primary/20 transition">
+          <.icon name="hero-arrow-right-on-rectangle" class="size-8 text-primary" />
+        </div>
+        <h2 class="card-title mt-2">ルームに参加</h2>
+        <p class="text-sm text-base-content/70">
+          ルーム番号を入力して、既存のルームに参加します。
+        </p>
+      </div>
+    </.link>
+  </div>
+</Layouts.app>
@@ -0,0 +1,89 @@
+defmodule Rsh26poolWeb.RoomController do
+  use Rsh26poolWeb, :controller
+
+  import Phoenix.Component, only: [to_form: 1, to_form: 2]
+
+  alias Rsh26pool.Voting
+  alias Rsh26poolWeb.Auth
+
+  def new(conn, _params) do
+    render(conn, :new,
+      form: to_form(Voting.change_room_creation()),
+      page_title: "ルームを作成"
+    )
+  end
+
+  def create(conn, %{"room" => room_params}) do
+    case Voting.create_room(room_params) do
+      {:ok, %{room: room, owner: owner}} ->
+        conn
+        |> Auth.log_in_participant(owner)
+        |> put_flash(
+          :info,
+          "ルーム「#{room.name}」を作成しました。ルーム番号は #{room.room_number} です。"
+        )
+        |> redirect(to: ~p"/manage/#{room.room_number}")
+
+      {:error, changeset} ->
+        conn
+        |> put_flash(:error, "ルームを作成できませんでした。入力内容を確認してください。")
+        |> render(:new, form: to_form(changeset), page_title: "ルームを作成")
+    end
+  end
+
+  def enter_form(conn, params) do
+    render(conn, :enter,
+      form: enter_form_data(params["room"] || "", ""),
+      page_title: "ルームに参加"
+    )
+  end
+
+  def enter(conn, %{"enter" => %{"room_number" => number, "name" => name}}) do
+    number = String.trim(number || "")
+    name = String.trim(name || "")
+
+    cond do
+      number == "" or name == "" ->
+        conn
+        |> put_flash(:error, "ルーム番号と名前を入力してください。")
+        |> render(:enter, form: enter_form_data(number, name), page_title: "ルームに参加")
+
+      true ->
+        enter_room(conn, number, name)
+    end
+  end
+
+  def logout(conn, _params) do
+    conn
+    |> Auth.log_out_participant()
+    |> put_flash(:info, "ログアウトしました。")
+    |> redirect(to: ~p"/")
+  end
+
+  defp enter_room(conn, number, name) do
+    case Voting.get_room_by_number(number) do
+      nil ->
+        conn
+        |> put_flash(:error, "ルーム番号「#{number}」のルームが見つかりません。")
+        |> render(:enter, form: enter_form_data(number, name), page_title: "ルームに参加")
+
+      room ->
+        case Voting.join_room(room, %{"name" => name}) do
+          {:ok, participant} ->
+            conn
+            |> Auth.log_in_participant(participant)
+            |> put_flash(:info, "ルーム「#{room.name}」に参加しました。")
+            |> redirect(to: ~p"/vote/#{room.room_number}")
+
+          {:error, _changeset} ->
+            conn
+            |> put_flash(:error, "参加できませんでした。名前は40文字以内で入力してください。")
+            |> render(:enter, form: enter_form_data(number, name), page_title: "ルームに参加")
+        end
+    end
+  end
+
+  defp enter_form_data(number, name) do
+    to_form(%{"room_number" => number, "name" => name}, as: :enter)
+  end
+end
@@ -0,0 +1,8 @@
+defmodule Rsh26poolWeb.RoomHTML do
+  @moduledoc """
+  Templates rendered by `RoomController` (room creation and joining).
+  """
+  use Rsh26poolWeb, :html
+
+  embed_templates "room_html/*"
+end
@@ -0,0 +1,40 @@
+<Layouts.app flash={@flash} current_participant={@current_participant}>
+  <div class="mx-auto max-w-md">
+    <.header>
+      ルームに参加
+      <:subtitle>ルーム番号とあなたの名前を入力してください。</:subtitle>
+    </.header>
+
+    <div class="card bg-base-100 border border-base-200 shadow-sm mt-4">
+      <div class="card-body">
+        <.form for={@form} action={~p"/enter"} method="post" id="enter-room-form">
+          <.input
+            field={@form[:room_number]}
+            type="text"
+            label="ルーム番号"
+            placeholder="6桁の番号"
+            inputmode="numeric"
+            required
+          />
+
+          <.input
+            field={@form[:name]}
+            type="text"
+            label="あなたの名前"
+            placeholder="例：たろう"
+            required
+          />
+
+          <div class="flex items-center justify-between gap-3 mt-2">
+            <.link navigate={~p"/"} class="btn btn-ghost btn-sm">
+              戻る
+            </.link>
+            <button type="submit" class="btn btn-primary">
+              <.icon name="hero-arrow-right-on-rectangle" class="size-4" /> 参加する
+            </button>
+          </div>
+        </.form>
+      </div>
+    </div>
+  </div>
+</Layouts.app>
@@ -0,0 +1,65 @@
+<Layouts.app flash={@flash} current_participant={@current_participant}>
+  <div class="mx-auto max-w-xl">
+    <.header>
+      ルームを作成
+      <:subtitle>投票の設定を入力してください。</:subtitle>
+    </.header>
+
+    <div class="card bg-base-100 border border-base-200 shadow-sm mt-4">
+      <div class="card-body">
+        <.form for={@form} action={~p"/create"} method="post" id="create-room-form">
+          <.input
+            field={@form[:name]}
+            type="text"
+            label="ルーム名"
+            placeholder="例：今日のランチ投票"
+            required
+          />
+
+          <.input
+            field={@form[:votes_per_user]}
+            type="number"
+            label="一人あたりの投票数"
+            min="1"
+            max="50"
+            required
+          />
+
+          <div class="divider text-sm text-base-content/60">追加オプション</div>
+
+          <.input
+            field={@form[:grouping_mode]}
+            type="checkbox"
+            label="グルーピングモードを有効にする（班分けアプリになります）"
+          />
+
+          <.input
+            field={@form[:leader_threshold]}
+            type="number"
+            label="リーダーになるのに必要な票数（グルーピングモードのときのみ使用）"
+            min="1"
+            max="50"
+          />
+
+          <.input
+            field={@form[:closes_at_local]}
+            type="datetime-local"
+            label="投票終了日時（任意・日本時間）"
+          />
+          <p class="text-xs text-base-content/60 -mt-1 mb-3">
+            指定すると、その日時に自動的に投票が終了します。
+          </p>
+
+          <div class="flex items-center justify-between gap-3 mt-2">
+            <.link navigate={~p"/"} class="btn btn-ghost btn-sm">
+              戻る
+            </.link>
+            <button type="submit" class="btn btn-primary">
+              <.icon name="hero-plus" class="size-4" /> ルームを作成
+            </button>
+          </div>
+        </.form>
+      </div>
+    </div>
+  </div>
+</Layouts.app>
@@ -0,0 +1,237 @@
+defmodule Rsh26poolWeb.ManageLive do
+  @moduledoc """
+  The owner's management page: rename the room, end voting, and watch results
+  (with vote counts) and participants update in real time. In grouping mode the
+  computed teams are shown once voting has ended.
+  """
+  use Rsh26poolWeb, :live_view
+
+  alias Rsh26pool.JST
+  alias Rsh26pool.Voting
+
+  @impl true
+  def mount(%{"room_number" => number}, _session, socket) do
+    room = number |> Voting.get_room_by_number() |> Voting.ensure_closed()
+
+    if connected?(socket), do: Voting.subscribe(room.id)
+
+    {:ok,
+     socket
+     |> assign(:room, room)
+     |> assign(:participant, socket.assigns.current_participant)
+     |> assign(:page_title, "管理 - #{room.name}")
+     |> assign(:name_form, to_form(Voting.change_room_settings(room)))
+     |> load_state()}
+  end
+
+  @impl true
+  def handle_event("rename", %{"room" => params}, socket) do
+    case Voting.update_room_settings(socket.assigns.room, params) do
+      {:ok, room} ->
+        {:noreply,
+         socket
+         |> assign(:room, room)
+         |> assign(:name_form, to_form(Voting.change_room_settings(room)))
+         |> put_flash(:info, "ルーム名を変更しました。")}
+
+      {:error, changeset} ->
+        {:noreply, assign(socket, :name_form, to_form(changeset))}
+    end
+  end
+
+  def handle_event("close", _params, socket) do
+    {:ok, room} = Voting.close_room(socket.assigns.room)
+
+    {:noreply,
+     socket
+     |> assign(:room, room)
+     |> put_flash(:info, "投票を終了しました。")
+     |> load_state()}
+  end
+
+  @impl true
+  def handle_info({:voting, :room_updated}, socket) do
+    room =
+      socket.assigns.room.room_number |> Voting.get_room_by_number() |> Voting.ensure_closed()
+
+    {:noreply, socket |> assign(:room, room) |> load_state()}
+  end
+
+  def handle_info({:voting, _event}, socket) do
+    {:noreply, load_state(socket)}
+  end
+
+  ## State ---------------------------------------------------------------
+
+  defp load_state(socket) do
+    room = socket.assigns.room
+    open? = Voting.room_open?(room)
+
+    socket
+    |> assign(:open?, open?)
+    |> assign(:results, Voting.results(room))
+    |> assign(:participants, Voting.list_participants(room))
+    |> assign(:grouping, if(not open? and room.grouping_mode, do: Voting.group_assignments(room)))
+  end
+
+  ## Render --------------------------------------------------------------
+
+  @impl true
+  def render(assigns) do
+    ~H"""
+    <Layouts.app flash={@flash} current_participant={@current_participant}>
+      <.header>
+        管理ページ
+        <:subtitle>{@room.name}</:subtitle>
+        <:actions>
+          <span :if={@open?} class="badge badge-success gap-1">
+            <.icon name="hero-hand-raised" class="size-4" /> 投票受付中
+          </span>
+          <span :if={not @open?} class="badge badge-neutral gap-1">
+            <.icon name="hero-lock-closed" class="size-4" /> 終了
+          </span>
+        </:actions>
+      </.header>
+
+      <div class="card bg-base-100 border border-base-200 shadow-sm">
+        <div class="card-body py-4">
+          <p class="text-sm text-base-content/70">参加者に伝えるルーム番号</p>
+          <p class="text-3xl font-mono font-bold tracking-widest">{@room.room_number}</p>
+          <p class="text-sm text-base-content/60">
+            投票ページ：<span class="font-mono">{url(~p"/vote/#{@room.room_number}")}</span>
+          </p>
+          <p :if={@room.closes_at} class="text-sm text-base-content/70 flex items-center gap-1 mt-1">
+            <.icon name="hero-clock" class="size-4" /> 自動終了予定：{JST.format(@room.closes_at)}（日本時間）
+          </p>
+        </div>
+      </div>
+
+      <div class="grid gap-4 sm:grid-cols-2">
+        <div class="card bg-base-100 border border-base-200 shadow-sm">
+          <div class="card-body py-4">
+            <h2 class="card-title text-base">
+              <.icon name="hero-pencil-square" class="size-5" /> ルーム名を変更
+            </h2>
+            <.form for={@name_form} phx-submit="rename" id="rename-form" class="flex flex-col gap-2">
+              <.input field={@name_form[:name]} type="text" />
+              <div class="flex justify-end">
+                <button type="submit" class="btn btn-primary btn-sm">保存</button>
+              </div>
+            </.form>
+          </div>
+        </div>
+
+        <div class="card bg-base-100 border border-base-200 shadow-sm">
+          <div class="card-body py-4">
+            <h2 class="card-title text-base">
+              <.icon name="hero-lock-closed" class="size-5" /> 投票の終了
+            </h2>
+            <%= if @open? do %>
+              <p class="text-sm text-base-content/70">
+                投票を終了すると、参加者は投票できなくなります。 <span :if={@room.grouping_mode}>終了時にグループ分けが行われます。</span>
+              </p>
+              <div class="flex justify-end">
+                <button
+                  type="button"
+                  phx-click="close"
+                  data-confirm="投票を終了しますか？この操作は取り消せません。"
+                  class="btn btn-error btn-sm"
+                >
+                  投票を終了する
+                </button>
+              </div>
+            <% else %>
+              <p class="text-sm text-base-content/70">この投票は終了しています。</p>
+            <% end %>
+          </div>
+        </div>
+      </div>
+
+      <div>
+        <h2 class="font-semibold mb-2 flex items-center gap-2">
+          <.icon name="hero-trophy" class="size-5 text-warning" /> 現在の結果
+          <span class="badge badge-sm">{length(@results)} 件</span>
+        </h2>
+        <p :if={@results == []} class="text-base-content/60 text-sm">まだ投稿がありません。</p>
+        <ol class="space-y-2">
+          <li
+            :for={{result, index} <- Enum.with_index(@results)}
+            class={[
+              "flex items-center justify-between gap-3 p-3 rounded-box border",
+              index == 0 && @results != [] && "border-warning bg-warning/10",
+              index != 0 && "border-base-200 bg-base-100"
+            ]}
+          >
+            <div class="flex items-center gap-3 min-w-0">
+              <span class="font-bold text-lg w-6 text-center">{index + 1}</span>
+              <div class="min-w-0">
+                <p class="truncate">{result.idea.text}</p>
+                <p :if={@room.grouping_mode} class="text-xs text-base-content/60">
+                  提案者：{result.idea.participant.name}
+                </p>
+              </div>
+            </div>
+            <span class="badge badge-lg gap-1">
+              <.icon name="hero-hand-thumb-up" class="size-4" /> {result.count}
+            </span>
+          </li>
+        </ol>
+      </div>
+
+      <div :if={@grouping}>
+        <h2 class="font-semibold mb-2 flex items-center gap-2">
+          <.icon name="hero-user-group" class="size-5 text-primary" /> グループ分けの結果
+        </h2>
+        <p :if={@grouping.groups == []} class="text-base-content/70 text-sm">
+          リーダーになる人が決まりませんでした（十分な票を集めた意見がありません）。
+        </p>
+        <div class="grid gap-3 sm:grid-cols-2">
+          <div
+            :for={group <- @grouping.groups}
+            class="card bg-base-100 border border-base-200 shadow-sm"
+          >
+            <div class="card-body py-4">
+              <h3 class="font-bold flex items-center gap-2">
+                <.icon name="hero-user-group" class="size-5 text-primary" />
+                {group.leader.name} グループ
+              </h3>
+              <p class="text-sm text-base-content/70">テーマ：{group.opinion && group.opinion.text}</p>
+              <ul class="mt-2 space-y-1 text-sm">
+                <li class="flex items-center gap-2 font-semibold">
+                  <.icon name="hero-trophy" class="size-4 text-warning" /> {group.leader.name}（リーダー）
+                </li>
+                <li :for={member <- group.members} class="flex items-center gap-2 pl-6">
+                  {member.name}
+                </li>
+              </ul>
+            </div>
+          </div>
+        </div>
+        <p :if={@grouping.ungrouped != []} class="text-sm text-base-content/60 mt-2">
+          未割り当て：{Enum.map_join(@grouping.ungrouped, "、", & &1.name)}
+        </p>
+      </div>
+
+      <div>
+        <h2 class="font-semibold mb-2 flex items-center gap-2">
+          <.icon name="hero-users" class="size-5" /> 参加者
+          <span class="badge badge-sm">{length(@participants)} 人</span>
+        </h2>
+        <div class="flex flex-wrap gap-2">
+          <span
+            :for={p <- @participants}
+            class={[
+              "badge badge-lg",
+              p.role == "owner" && "badge-primary",
+              p.role != "owner" && "badge-ghost"
+            ]}
+          >
+            {p.name}
+            <span :if={p.role == "owner"} class="ml-1 text-xs">(オーナー)</span>
+          </span>
+        </div>
+      </div>
+    </Layouts.app>
+    """
+  end
+end
@@ -0,0 +1,367 @@
+defmodule Rsh26poolWeb.VoteLive do
+  @moduledoc """
+  The voting page. Choices are shown in a per-viewer shuffled order and their
+  vote counts are hidden while voting is open. In grouping mode the participant
+  posts a single opinion and votes for the groups they want to join; once voting
+  closes they see their assigned group.
+  """
+  use Rsh26poolWeb, :live_view
+
+  alias Rsh26pool.Voting
+
+  @impl true
+  def mount(%{"room_number" => number}, _session, socket) do
+    participant = socket.assigns.current_participant
+    room = number |> Voting.get_room_by_number() |> Voting.ensure_closed()
+
+    if connected?(socket), do: Voting.subscribe(room.id)
+
+    {:ok,
+     socket
+     |> assign(:room, room)
+     |> assign(:participant, participant)
+     |> assign(:page_title, "投票 - #{room.name}")
+     |> load_state()}
+  end
+
+  @impl true
+  def handle_event("vote", %{"id" => id}, socket) do
+    case Voting.vote(socket.assigns.participant, String.to_integer(id)) do
+      {:ok, _} ->
+        {:noreply, refresh_votes(socket)}
+
+      {:error, :already_voted} ->
+        {:noreply, refresh_votes(socket)}
+
+      {:error, :limit_reached} ->
+        {:noreply, put_flash(socket, :error, "投票できる数の上限に達しました。")}
+
+      {:error, :closed} ->
+        {:noreply, socket |> put_flash(:error, "投票は終了しました。") |> reload_room()}
+
+      {:error, _} ->
+        {:noreply, put_flash(socket, :error, "投票できませんでした。")}
+    end
+  end
+
+  def handle_event("unvote", %{"id" => id}, socket) do
+    case Voting.unvote(socket.assigns.participant, String.to_integer(id)) do
+      :ok ->
+        {:noreply, refresh_votes(socket)}
+
+      {:error, :closed} ->
+        {:noreply, socket |> put_flash(:error, "投票は終了しました。") |> reload_room()}
+
+      {:error, _} ->
+        {:noreply, refresh_votes(socket)}
+    end
+  end
+
+  def handle_event("post_idea", %{"idea" => %{"text" => text}}, socket) do
+    case Voting.create_idea(socket.assigns.room, socket.assigns.participant, %{"text" => text}) do
+      {:ok, _idea} ->
+        message = if socket.assigns.room.grouping_mode, do: "意見を保存しました。", else: "アイデアを投稿しました。"
+        {:noreply, socket |> put_flash(:info, message) |> load_state()}
+
+      {:error, :closed} ->
+        {:noreply, socket |> put_flash(:error, "投票は終了しました。") |> reload_room()}
+
+      {:error, %Ecto.Changeset{} = changeset} ->
+        {:noreply, assign(socket, :idea_form, to_form(changeset, as: :idea))}
+    end
+  end
+
+  @impl true
+  def handle_info({:voting, :ideas_changed}, socket) do
+    {:noreply,
+     assign(
+       socket,
+       :ideas,
+       Voting.shuffled_ideas(socket.assigns.room, socket.assigns.participant.token)
+     )}
+  end
+
+  def handle_info({:voting, :room_updated}, socket) do
+    {:noreply, reload_room(socket)}
+  end
+
+  def handle_info({:voting, _event}, socket), do: {:noreply, socket}
+
+  ## State helpers --------------------------------------------------------
+
+  defp load_state(socket) do
+    room = socket.assigns.room
+    participant = socket.assigns.participant
+    open? = Voting.room_open?(room)
+
+    socket
+    |> assign(:open?, open?)
+    |> assign(:votes_remaining, Voting.votes_remaining(room, participant))
+    |> assign(:voted_ids, Voting.voted_idea_ids(participant))
+    |> assign(:ideas, Voting.shuffled_ideas(room, participant.token))
+    |> assign_idea_form()
+    |> assign_results(open?)
+  end
+
+  defp refresh_votes(socket) do
+    participant = socket.assigns.participant
+
+    socket
+    |> assign(:voted_ids, Voting.voted_idea_ids(participant))
+    |> assign(:votes_remaining, Voting.votes_remaining(socket.assigns.room, participant))
+  end
+
+  defp reload_room(socket) do
+    room =
+      socket.assigns.room.room_number |> Voting.get_room_by_number() |> Voting.ensure_closed()
+
+    socket |> assign(:room, room) |> load_state()
+  end
+
+  defp assign_idea_form(socket) do
+    room = socket.assigns.room
+
+    if room.grouping_mode do
+      opinion = Voting.get_participant_idea(room, socket.assigns.participant)
+      text = if opinion, do: opinion.text, else: ""
+
+      socket
+      |> assign(:my_opinion, opinion)
+      |> assign(:idea_form, to_form(%{"text" => text}, as: :idea))
+    else
+      socket
+      |> assign(:my_opinion, nil)
+      |> assign(:idea_form, to_form(%{"text" => ""}, as: :idea))
+    end
+  end
+
+  defp assign_results(socket, true) do
+    socket |> assign(:results, []) |> assign(:grouping, nil) |> assign(:my_group, nil)
+  end
+
+  defp assign_results(socket, false) do
+    room = socket.assigns.room
+
+    if room.grouping_mode do
+      grouping = Voting.group_assignments(room)
+
+      socket
+      |> assign(:grouping, grouping)
+      |> assign(:my_group, find_my_group(grouping, socket.assigns.participant))
+      |> assign(:results, [])
+    else
+      socket
+      |> assign(:results, Voting.results(room))
+      |> assign(:grouping, nil)
+      |> assign(:my_group, nil)
+    end
+  end
+
+  defp find_my_group(%{groups: groups}, participant) do
+    Enum.find(groups, fn g ->
+      g.leader.id == participant.id or Enum.any?(g.members, &(&1.id == participant.id))
+    end)
+  end
+
+  defp find_my_group(_grouping, _participant), do: nil
+
+  ## Render ---------------------------------------------------------------
+
+  @impl true
+  def render(assigns) do
+    ~H"""
+    <Layouts.app flash={@flash} current_participant={@current_participant}>
+      <.header>
+        {@room.name}
+        <:subtitle>
+          ルーム番号 <span class="font-mono font-semibold">{@room.room_number}</span>
+          <span :if={@room.grouping_mode} class="badge badge-accent badge-sm ml-2">グルーピングモード</span>
+        </:subtitle>
+        <:actions>
+          <span :if={@open?} class="badge badge-success gap-1">
+            <.icon name="hero-hand-raised" class="size-4" /> 投票受付中
+          </span>
+          <span :if={not @open?} class="badge badge-neutral gap-1">
+            <.icon name="hero-lock-closed" class="size-4" /> 終了
+          </span>
+        </:actions>
+      </.header>
+
+      <%= if @open? do %>
+        <div class="alert bg-base-200 border border-base-300">
+          <.icon name="hero-ticket" class="size-5 text-primary" />
+          <span>
+            残りの投票数：<span class="font-bold text-lg">{@votes_remaining}</span> / {@room.votes_per_user}
+          </span>
+        </div>
+
+        <div class="card bg-base-100 border border-base-200 shadow-sm">
+          <div class="card-body">
+            <h2 class="card-title text-base">
+              <%= if @room.grouping_mode do %>
+                あなたの意見（1つだけ投稿できます）
+              <% else %>
+                新しいアイデアを投稿
+              <% end %>
+            </h2>
+            <.form for={@idea_form} phx-submit="post_idea" id="idea-form" class="flex flex-col gap-2">
+              <.input
+                field={@idea_form[:text]}
+                type="text"
+                placeholder={if @room.grouping_mode, do: "例：みんなで公園を掃除したい", else: "例：焼肉に行きたい"}
+              />
+              <div class="flex justify-end">
+                <button type="submit" class="btn btn-primary btn-sm">
+                  <.icon name="hero-plus" class="size-4" />
+                  {if @room.grouping_mode and @my_opinion, do: "意見を更新", else: "投稿する"}
+                </button>
+              </div>
+            </.form>
+          </div>
+        </div>
+
+        <div>
+          <h2 class="font-semibold mb-2 flex items-center gap-2">
+            <.icon name="hero-hand-thumb-up" class="size-5 text-primary" />
+            {if @room.grouping_mode, do: "参加したいグループに投票", else: "アイデアに投票"}
+          </h2>
+
+          <p :if={@ideas == []} class="text-base-content/60 text-sm py-6 text-center">
+            まだ投稿がありません。最初の一つを投稿してみましょう。
+          </p>
+
+          <ul class="space-y-2">
+            <li
+              :for={idea <- @ideas}
+              id={"idea-#{idea.id}"}
+              class="flex items-center justify-between gap-3 p-3 rounded-box border border-base-200 bg-base-100"
+            >
+              <div class="min-w-0">
+                <p class="truncate">{idea.text}</p>
+                <p :if={@room.grouping_mode} class="text-xs text-base-content/60">
+                  提案者：{idea.participant.name}
+                </p>
+              </div>
+
+              <%= if MapSet.member?(@voted_ids, idea.id) do %>
+                <button
+                  type="button"
+                  phx-click="unvote"
+                  phx-value-id={idea.id}
+                  class="btn btn-success btn-sm gap-1 shrink-0"
+                >
+                  <.icon name="hero-check-badge" class="size-4" /> 投票済み
+                </button>
+              <% else %>
+                <button
+                  type="button"
+                  phx-click="vote"
+                  phx-value-id={idea.id}
+                  disabled={@votes_remaining <= 0}
+                  class="btn btn-outline btn-sm shrink-0"
+                >
+                  投票する
+                </button>
+              <% end %>
+            </li>
+          </ul>
+        </div>
+      <% else %>
+        <div class="alert alert-info">
+          <.icon name="hero-lock-closed" class="size-5" />
+          <span>この投票は終了しました。</span>
+        </div>
+
+        <%= if @room.grouping_mode do %>
+          <.grouping_results grouping={@grouping} my_group={@my_group} participant={@participant} />
+        <% else %>
+          <.normal_results results={@results} />
+        <% end %>
+      <% end %>
+    </Layouts.app>
+    """
+  end
+
+  ## Result components ----------------------------------------------------
+
+  attr :results, :list, required: true
+
+  defp normal_results(assigns) do
+    ~H"""
+    <div>
+      <h2 class="font-semibold mb-2 flex items-center gap-2">
+        <.icon name="hero-trophy" class="size-5 text-warning" /> 結果
+      </h2>
+      <p :if={@results == []} class="text-base-content/60 text-sm">投稿はありませんでした。</p>
+      <ol class="space-y-2">
+        <li
+          :for={{result, index} <- Enum.with_index(@results)}
+          class={[
+            "flex items-center justify-between gap-3 p-3 rounded-box border",
+            index == 0 && "border-warning bg-warning/10",
+            index != 0 && "border-base-200 bg-base-100"
+          ]}
+        >
+          <div class="flex items-center gap-3 min-w-0">
+            <span class="font-bold text-lg w-6 text-center">{index + 1}</span>
+            <span class="truncate">{result.idea.text}</span>
+          </div>
+          <span class="badge badge-lg gap-1">
+            <.icon name="hero-hand-thumb-up" class="size-4" /> {result.count}
+          </span>
+        </li>
+      </ol>
+    </div>
+    """
+  end
+
+  attr :grouping, :map, required: true
+  attr :my_group, :map, default: nil
+  attr :participant, :map, required: true
+
+  defp grouping_results(assigns) do
+    ~H"""
+    <div class="space-y-4">
+      <div :if={@my_group} class="card bg-primary/10 border border-primary">
+        <div class="card-body py-4">
+          <p class="text-sm text-base-content/70">あなたのグループ</p>
+          <p class="text-lg font-bold flex items-center gap-2">
+            <.icon name="hero-user-group" class="size-5 text-primary" />
+            {@my_group.leader.name} さんのグループ
+          </p>
+          <p class="text-sm">テーマ：{@my_group.opinion && @my_group.opinion.text}</p>
+        </div>
+      </div>
+
+      <p :if={@grouping.groups == []} class="text-base-content/70 text-sm">
+        リーダーになる人が決まりませんでした（十分な票を集めた意見がありません）。
+      </p>
+
+      <div class="grid gap-3 sm:grid-cols-2">
+        <div
+          :for={group <- @grouping.groups}
+          class="card bg-base-100 border border-base-200 shadow-sm"
+        >
+          <div class="card-body py-4">
+            <h3 class="font-bold flex items-center gap-2">
+              <.icon name="hero-user-group" class="size-5 text-primary" />
+              {group.leader.name} グループ
+            </h3>
+            <p class="text-sm text-base-content/70">
+              テーマ：{group.opinion && group.opinion.text}
+            </p>
+            <ul class="mt-2 space-y-1 text-sm">
+              <li class="flex items-center gap-2 font-semibold">
+                <.icon name="hero-trophy" class="size-4 text-warning" /> {group.leader.name}（リーダー）
+              </li>
+              <li :for={member <- group.members} class="flex items-center gap-2 pl-6">
+                {member.name}
+              </li>
+            </ul>
+          </div>
+        </div>
+      </div>
+    </div>
+    """
+  end
+end
@@ -1,6 +1,8 @@
 defmodule Rsh26poolWeb.Router do
  use Rsh26poolWeb, :router

+  import Rsh26poolWeb.Auth, only: [fetch_current_participant: 2]
+
  pipeline :browser do
    plug :accepts, ["html"]
    plug :fetch_session
@@ -8,6 +10,7 @@ defmodule Rsh26poolWeb.Router do
    plug :put_root_layout, html: {Rsh26poolWeb.Layouts, :root}
    plug :protect_from_forgery
    plug :put_secure_browser_headers
+    plug :fetch_current_participant
  end

  pipeline :api do
@@ -18,6 +21,22 @@ defmodule Rsh26poolWeb.Router do
    pipe_through :browser

    get "/", PageController, :home
+
+    get "/create", RoomController, :new
+    post "/create", RoomController, :create
+    get "/enter", RoomController, :enter_form
+    post "/enter", RoomController, :enter
+    delete "/logout", RoomController, :logout
+
+    live_session :voter,
+      on_mount: [{Rsh26poolWeb.Auth, :require_participant}] do
+      live "/vote/:room_number", VoteLive
+    end
+
+    live_session :owner,
+      on_mount: [{Rsh26poolWeb.Auth, :require_owner}] do
+      live "/manage/:room_number", ManageLive
+    end
  end

  # Other scopes may use custom stacks.