who_need_help/lib/who_need_help/activities.ex

652 lines
19 KiB
Elixir

defmodule WhoNeedHelp.Activities do
@moduledoc """
Social plans are separate from urgent-help assignments and reputation.
"""
import Ecto.Query
alias WhoNeedHelp.Accounts
alias WhoNeedHelp.Accounts.Scope
alias WhoNeedHelp.Activities.{Activity, Message, Participant}
alias WhoNeedHelp.Catalog
alias WhoNeedHelp.Catalog.Category
alias WhoNeedHelp.Pagination
alias WhoNeedHelp.Repo
alias WhoNeedHelp.Trust
alias WhoNeedHelp.Trust.Block
@topic "activities"
def subscribe, do: Phoenix.PubSub.subscribe(WhoNeedHelp.PubSub, @topic)
def subscribe_activity(id),
do: Phoenix.PubSub.subscribe(WhoNeedHelp.PubSub, "activity:#{id}")
def notify_activity_updated(id) do
activity = load_activity(id)
broadcast({:activity_updated, activity})
broadcast_activity(id, {:activity_updated, activity})
:ok
end
def list_open_activities(%Scope{user: user}, filters \\ %{}) do
paginate_open_activities(%Scope{user: user}, filters).entries
end
def paginate_open_activities(%Scope{user: user}, filters \\ %{}, options \\ []) do
now = DateTime.utc_now(:second)
limit = Pagination.limit(options)
cursor = Pagination.cursor(options)
public_creator = Accounts.public_user_query(social_identities: true)
Activity
|> where(
[activity],
activity.status == :open and activity.starts_at > ^now and
activity.join_deadline > ^now and is_nil(activity.hidden_at)
)
|> where(
[activity],
activity.creator_id not in subquery(
from block in Block, where: block.blocker_id == ^user.id, select: block.blocked_id
)
)
|> where(
[activity],
activity.creator_id not in subquery(
from block in Block, where: block.blocked_id == ^user.id, select: block.blocker_id
)
)
|> maybe_filter_category(filters["category_id"] || filters[:category_id])
|> after_open_activity(cursor)
|> order_by([activity], asc: activity.starts_at, asc: activity.id)
|> limit(^(limit + 1))
|> with_approved_participant_count()
|> preload([activity], category: :parent, creator: ^public_creator)
|> Repo.all()
|> Pagination.page(limit, &{&1.starts_at, &1.id})
end
def list_my_activities(%Scope{user: user}) do
paginate_my_activities(%Scope{user: user}).entries
end
def paginate_my_activities(%Scope{user: user}, options \\ []) do
limit = Pagination.limit(options)
cursor = Pagination.cursor(options)
Activity
|> join(:inner, [activity], participant in Participant,
on:
participant.activity_id == activity.id and participant.user_id == ^user.id and
participant.status in [:requested, :approved]
)
|> before_my_activity(cursor)
|> order_by([activity], desc: activity.starts_at, desc: activity.id)
|> limit(^(limit + 1))
|> with_approved_participant_count()
|> preload([activity], category: :parent)
|> Repo.all()
|> Pagination.page(limit, &{&1.starts_at, &1.id})
end
defp after_open_activity(query, nil), do: query
defp after_open_activity(query, {starts_at, id}) do
where(
query,
[activity],
activity.starts_at > ^starts_at or
(activity.starts_at == ^starts_at and activity.id > ^id)
)
end
defp before_my_activity(query, nil), do: query
defp before_my_activity(query, {starts_at, id}) do
where(
query,
[activity],
activity.starts_at < ^starts_at or
(activity.starts_at == ^starts_at and activity.id < ^id)
)
end
defp before_message(query, nil), do: query
defp before_message(query, {inserted_at, id}) do
where(
query,
[message],
message.inserted_at < ^inserted_at or
(message.inserted_at == ^inserted_at and message.id < ^id)
)
end
def get_activity(%Scope{user: user}, id) do
case get_loaded_activity(id) do
nil ->
{:error, :not_found}
activity ->
cond do
activity.creator_id == user.id ->
{:ok, activity}
approved_participant?(activity, user.id) ->
{:ok, activity}
not is_nil(activity.hidden_at) ->
{:error, :not_found}
Trust.blocked_between?(activity.creator_id, user.id) ->
{:error, :not_found}
activity.status == :open ->
{:ok, activity_for_viewer(activity, user.id)}
true ->
{:error, :not_found}
end
end
end
def paginate_messages(%Scope{user: user}, %Activity{} = activity, options \\ []) do
if activity.creator_id == user.id or approved_participant?(activity, user.id) do
limit = Pagination.limit(options, 50)
cursor = Pagination.cursor(options)
public_user = Accounts.public_user_query()
page =
Message
|> where([message], message.activity_id == ^activity.id)
|> before_message(cursor)
|> order_by([message], desc: message.inserted_at, desc: message.id)
|> limit(^(limit + 1))
|> preload([message], sender: ^public_user)
|> Repo.all()
|> Pagination.page(limit, &{&1.inserted_at, &1.id})
%{page | entries: Enum.reverse(page.entries)}
else
%Pagination.Page{}
end
end
def change_activity(%Activity{} = activity, attrs \\ %{}) do
activity
|> Activity.create_changeset(attrs)
|> validate_category_and_data()
end
def create_activity(%Scope{user: user} = scope, attrs) do
result =
with {:ok, _limit} <- Trust.authorize_action(scope, :create_activity) do
Repo.transact(fn ->
with {:ok, activity} <-
%Activity{creator_id: user.id}
|> Activity.create_changeset(attrs)
|> validate_category_and_data()
|> Repo.insert(),
{:ok, _participant} <-
%Participant{}
|> Participant.changeset(%{
activity_id: activity.id,
user_id: user.id,
role: :organizer,
status: :approved,
reviewed_at: DateTime.utc_now(:second)
})
|> Repo.insert(),
{:ok, _audit} <-
Trust.audit(user.id, "activity.created", "activity", activity.id, %{
"category_id" => activity.category_id
}) do
{:ok, activity}
end
end)
end
with {:ok, activity} <- result do
activity = load_activity(activity.id)
broadcast({:activity_created, activity})
{:ok, activity}
end
end
def request_to_join(%Scope{user: user} = scope, activity_id) do
result =
with {:ok, _limit} <- Trust.authorize_action(scope, :join_activity) do
Repo.transact(fn ->
activity = locked_activity(activity_id)
now = DateTime.utc_now(:second)
cond do
activity.creator_id == user.id ->
{:error, :organizer_already_joined}
activity.status != :open or not is_nil(activity.hidden_at) ->
{:error, :not_open}
DateTime.compare(activity.join_deadline, now) != :gt ->
{:error, :join_closed}
Trust.blocked_between?(activity.creator_id, user.id) ->
{:error, :blocked}
approved_count(activity.id) >= activity.capacity ->
{:error, :capacity_reached}
true ->
upsert_join_request(activity.id, user.id, now)
end
end)
end
after_participant_change(result, activity_id, :join_requested)
end
def approve_participant(%Scope{user: organizer}, participant_id) do
result =
Repo.transact(fn ->
participant = locked_participant(participant_id)
activity = locked_activity(participant.activity_id)
cond do
activity.creator_id != organizer.id ->
{:error, :forbidden}
participant.status != :requested ->
{:error, :invalid_transition}
activity.status != :open ->
{:error, :not_open}
Trust.blocked_between?(activity.creator_id, participant.user_id) ->
{:error, :blocked}
approved_count(activity.id) >= activity.capacity ->
{:error, :capacity_reached}
true ->
with {:ok, participant} <-
participant
|> Participant.changeset(%{
status: :approved,
reviewed_at: DateTime.utc_now(:second)
})
|> Repo.update(),
{:ok, _audit} <-
Trust.audit(
organizer.id,
"activity.participant_approved",
"activity_participant",
participant.id,
%{"activity_id" => activity.id, "user_id" => participant.user_id}
) do
{:ok, participant}
end
end
end)
after_participant_change(result, participant_activity_id(result), :participant_approved)
end
def decline_participant(%Scope{user: organizer}, participant_id) do
transition_participant(organizer.id, participant_id, :declined)
end
def leave_activity(%Scope{user: user}, activity_id) do
result =
Repo.transact(fn ->
participant =
Participant
|> where(
[participant],
participant.activity_id == ^activity_id and participant.user_id == ^user.id
)
|> lock("FOR UPDATE")
|> Repo.one()
cond do
is_nil(participant) ->
{:error, :not_found}
participant.role == :organizer ->
{:error, :organizer_cannot_leave}
participant.status not in [:requested, :approved] ->
{:error, :invalid_transition}
true ->
with {:ok, participant} <-
participant
|> Participant.changeset(%{
status: :left,
left_at: DateTime.utc_now(:second)
})
|> Repo.update(),
{:ok, _audit} <-
Trust.audit(user.id, "activity.left", "activity", activity_id) do
{:ok, participant}
end
end
end)
after_participant_change(result, activity_id, :participant_left)
end
def cancel_activity(%Scope{user: user}, activity_id) do
transition_activity(user.id, activity_id, :cancelled)
end
def complete_activity(%Scope{user: user}, activity_id) do
transition_activity(user.id, activity_id, :completed)
end
def send_message(%Scope{user: user} = scope, activity_id, attrs) do
with {:ok, _limit} <- Trust.authorize_action(scope, :send_activity_message),
{:ok, activity} <- get_activity(scope, activity_id),
true <- activity.status == :open,
true <- approved_participant?(activity, user.id) do
%Message{}
|> Message.changeset(%{
body: attrs["body"] || attrs[:body],
activity_id: activity.id,
sender_id: user.id
})
|> Repo.insert()
|> case do
{:ok, message} ->
message = Repo.preload(message, sender: Accounts.public_user_query())
Phoenix.PubSub.broadcast(
WhoNeedHelp.PubSub,
"activity:#{activity.id}",
{:activity_message, message}
)
{:ok, message}
other ->
other
end
else
false -> {:error, :forbidden}
other -> other
end
end
def coordinates_for(%Scope{user: user}, %Activity{} = activity) do
if activity.creator_id == user.id or approved_participant?(activity, user.id) do
Activity.exact_coordinates(activity)
else
Activity.public_coordinates(activity)
end
end
def participant_for(%Activity{} = activity, user_id) do
Enum.find(activity.participants, &(&1.user_id == user_id))
end
def approved_participant?(%Activity{} = activity, user_id) do
Enum.any?(
activity.participants,
&(&1.user_id == user_id and &1.status == :approved)
)
end
defp validate_category_and_data(changeset) do
category_id = Ecto.Changeset.get_field(changeset, :category_id)
case category_id && Repo.get(Category, category_id) do
%Category{mode: :activity, active: true} = category ->
data = Ecto.Changeset.get_field(changeset, :structured_data)
case Catalog.validate_structured_data(category, data) do
{:ok, clean} ->
Ecto.Changeset.put_change(changeset, :structured_data, clean)
{:error, errors} ->
Enum.reduce(
errors,
changeset,
&Ecto.Changeset.add_error(&2, :structured_data, &1)
)
end
_ ->
Ecto.Changeset.add_error(changeset, :category_id, "select an activity category")
end
end
defp upsert_join_request(activity_id, user_id, now) do
case Repo.get_by(Participant, activity_id: activity_id, user_id: user_id) do
nil ->
%Participant{}
|> Participant.changeset(%{
activity_id: activity_id,
user_id: user_id,
role: :participant,
status: :requested
})
|> Repo.insert()
%Participant{status: status} = participant when status in [:declined, :left] ->
participant
|> Participant.changeset(%{
status: :requested,
reviewed_at: nil,
left_at: nil
})
|> Repo.update()
%Participant{} ->
{:error, :already_joined}
end
|> case do
{:ok, participant} ->
with {:ok, _audit} <-
Trust.audit(user_id, "activity.join_requested", "activity", activity_id, %{
"requested_at" => DateTime.to_iso8601(now)
}) do
{:ok, participant}
end
other ->
other
end
end
defp transition_participant(organizer_id, participant_id, status) do
result =
Repo.transact(fn ->
participant = locked_participant(participant_id)
activity = locked_activity(participant.activity_id)
cond do
activity.creator_id != organizer_id ->
{:error, :forbidden}
participant.status != :requested ->
{:error, :invalid_transition}
true ->
with {:ok, participant} <-
participant
|> Participant.changeset(%{
status: status,
reviewed_at: DateTime.utc_now(:second)
})
|> Repo.update(),
{:ok, _audit} <-
Trust.audit(
organizer_id,
"activity.participant_#{status}",
"activity_participant",
participant.id,
%{"activity_id" => activity.id, "user_id" => participant.user_id}
) do
{:ok, participant}
end
end
end)
after_participant_change(result, participant_activity_id(result), :participant_declined)
end
defp transition_activity(user_id, activity_id, target_status) do
result =
Repo.transact(fn ->
activity = locked_activity(activity_id)
cond do
activity.creator_id != user_id ->
{:error, :forbidden}
activity.status != :open ->
{:error, :invalid_transition}
true ->
timestamp = DateTime.utc_now(:second)
attrs =
case target_status do
:cancelled -> %{status: :cancelled, cancelled_at: timestamp}
:completed -> %{status: :completed, completed_at: timestamp}
end
with {:ok, activity} <- activity |> Ecto.Changeset.change(attrs) |> Repo.update(),
{:ok, _audit} <-
Trust.audit(
user_id,
"activity.#{target_status}",
"activity",
activity.id
) do
{:ok, activity}
end
end
end)
with {:ok, activity} <- result do
activity = load_activity(activity.id)
broadcast({:activity_updated, activity})
broadcast_activity(activity.id, {:activity_updated, activity})
{:ok, activity}
end
end
defp after_participant_change({:ok, participant}, activity_id, event)
when is_binary(activity_id) do
activity = load_activity(activity_id)
broadcast({:activity_updated, activity})
broadcast_activity(activity.id, {event, participant})
{:ok, participant}
end
defp after_participant_change(result, _activity_id, _event), do: result
defp participant_activity_id({:ok, %Participant{activity_id: activity_id}}), do: activity_id
defp participant_activity_id(_result), do: nil
defp approved_count(activity_id) do
Repo.aggregate(
from(
participant in Participant,
where: participant.activity_id == ^activity_id and participant.status == :approved
),
:count
)
end
defp load_activity(id) do
Activity
|> Repo.get!(id)
|> preload_activity()
end
defp get_loaded_activity(id) do
Activity
|> Repo.get(id)
|> preload_activity()
end
defp preload_activity(nil), do: nil
defp preload_activity(activity) do
public_user = Accounts.public_user_query(social_identities: true)
public_sender = Accounts.public_user_query()
recent_messages =
Message
|> order_by([message], desc: message.inserted_at, desc: message.id)
|> limit(50)
|> preload([message], sender: ^public_sender)
Repo.preload(
activity,
category: :parent,
creator: public_user,
participants: [user: public_user],
messages: recent_messages
)
end
defp activity_for_viewer(activity, user_id) do
%{
activity
| messages: [],
participants:
Enum.filter(
activity.participants,
&(&1.status == :approved or &1.user_id == user_id)
)
}
end
defp with_approved_participant_count(query) do
counts =
Participant
|> where([participant], participant.status == :approved)
|> group_by([participant], participant.activity_id)
|> select([participant], %{
activity_id: participant.activity_id,
approved_count: count(participant.id)
})
query
|> join(:left, [activity], count in subquery(counts),
on: count.activity_id == activity.id,
as: :approved_counts
)
|> select_merge([approved_counts: count], %{
approved_participant_count: fragment("coalesce(?, 0)", count.approved_count)
})
end
defp locked_activity(id) do
Activity
|> where([activity], activity.id == ^id)
|> lock("FOR UPDATE")
|> Repo.one!()
end
defp locked_participant(id) do
Participant
|> where([participant], participant.id == ^id)
|> lock("FOR UPDATE")
|> Repo.one!()
end
defp maybe_filter_category(query, value) when value in [nil, ""], do: query
defp maybe_filter_category(query, value),
do: where(query, [activity], activity.category_id == ^value)
defp broadcast(message), do: Phoenix.PubSub.broadcast(WhoNeedHelp.PubSub, @topic, message)
defp broadcast_activity(id, message),
do: Phoenix.PubSub.broadcast(WhoNeedHelp.PubSub, "activity:#{id}", message)
end