init

src/routes/conversation/handlers.rs

@@ -0,0 +1,88 @@
+use crate::core::state::AppState;
+use crate::domain::dto::conversation::{
+    ConversationParticipantResponse, ConversationResponse, CreateConversationRequest,
+    ForkConversationRequest,
+};
+use crate::http::context::CurrentUser;
+use crate::http::error::HTTPError;
+use crate::models::{channel, channel_user, message, user};
+use axum::{Json, extract::{Path, State}};
+use chrono::Utc;
+use sea_orm::{ActiveModelTrait, ColumnTrait, EntityTrait, QueryFilter, QueryOrder, Set, TransactionTrait};
+use std::collections::HashSet;
+use uuid::Uuid;
+
+async fn member_ids(state: &AppState, channel_id: Uuid) -> Result<Vec<Uuid>, HTTPError> {
+    Ok(channel_user::Entity::find()
+        .filter(channel_user::Column::ChannelId.eq(channel_id))
+        .all(&state.db).await?.into_iter().map(|m| m.user_id).collect())
+}
+
+async fn response(state: &AppState, current_user_id: Uuid, channel: channel::Model) -> Result<ConversationResponse, HTTPError> {
+    let ids = member_ids(state, channel.id).await?;
+    let users = user::Entity::find().filter(user::Column::Id.is_in(ids.clone())).all(&state.db).await?;
+    let mut participants: Vec<_> = users.into_iter().map(|u| ConversationParticipantResponse { id: u.id, username: u.username }).collect();
+    participants.sort_by(|a, b| a.username.to_lowercase().cmp(&b.username.to_lowercase()));
+    let title = participants.iter().filter(|p| p.id != current_user_id).map(|p| p.username.clone()).collect::<Vec<_>>().join(", ");
+    let last_message = message::Entity::find().filter(message::Column::ChannelId.eq(channel.id)).order_by_desc(message::Column::Id).one(&state.db).await?.map(|m| m.content);
+    let unread_count = state.repositories.read_state.unread_counts(&[channel.id], current_user_id).await?.get(&channel.id).copied().unwrap_or(0);
+    Ok(ConversationResponse { id: channel.id, title: if title.is_empty() { "Discussion".into() } else { title }, participants, last_message, unread_count, created_at: channel.created_at, updated_at: channel.updated_at })
+}
+
+async fn create_channel(state: &AppState, ids: &[Uuid]) -> Result<channel::Model, HTTPError> {
+    let txn = state.db.begin().await?;
+    let channel = channel::ActiveModel { server_id: Set(None), category_id: Set(None), channel_type: Set(channel::ChannelType::DM), name: Set(None), ..Default::default() }.insert(&txn).await?;
+    for user_id in ids {
+        channel_user::ActiveModel { channel_id: Set(channel.id), user_id: Set(*user_id), role: Set("member".into()), joined_at: Set(Utc::now()), ..Default::default() }.insert(&txn).await?;
+    }
+    txn.commit().await?;
+    state.event_bus.emit("channel_created", channel.clone());
+    Ok(channel)
+}
+
+async fn validate_ids(state: &AppState, ids: &[Uuid]) -> Result<(), HTTPError> {
+    if ids.is_empty() { return Err(HTTPError::BadRequest("At least one participant is required".into())); }
+    let found = user::Entity::find().filter(user::Column::Id.is_in(ids.to_vec())).all(&state.db).await?;
+    if found.len() != ids.iter().collect::<HashSet<_>>().len() { return Err(HTTPError::BadRequest("Unknown participant".into())); }
+    Ok(())
+}
+
+#[utoipa::path(get, path = "/conversations", responses((status = 200, body = [ConversationResponse])), tag = "Conversations", security(("bearerAuth" = [])))]
+pub async fn list(user: CurrentUser, State(state): State<AppState>) -> Result<Json<Vec<ConversationResponse>>, HTTPError> {
+    let memberships = channel_user::Entity::find().filter(channel_user::Column::UserId.eq(user.id)).all(&state.db).await?;
+    let ids: Vec<_> = memberships.into_iter().map(|m| m.channel_id).collect();
+    if ids.is_empty() { return Ok(Json(Vec::new())); }
+    let channels = channel::Entity::find().filter(channel::Column::Id.is_in(ids)).filter(channel::Column::ChannelType.eq(channel::ChannelType::DM)).order_by_desc(channel::Column::UpdatedAt).all(&state.db).await?;
+    let mut result = Vec::with_capacity(channels.len());
+    for channel in channels { result.push(response(&state, user.id, channel).await?); }
+    Ok(Json(result))
+}
+
+#[utoipa::path(post, path = "/conversations", request_body = CreateConversationRequest, responses((status = 200, body = ConversationResponse)), tag = "Conversations", security(("bearerAuth" = [])))]
+pub async fn create(user: CurrentUser, State(state): State<AppState>, Json(payload): Json<CreateConversationRequest>) -> Result<Json<ConversationResponse>, HTTPError> {
+    let mut ids = payload.user_ids;
+    ids.push(user.id);
+    ids.sort_unstable(); ids.dedup();
+    validate_ids(&state, &ids).await?;
+    let channels = channel_user::Entity::find().filter(channel_user::Column::UserId.eq(user.id)).all(&state.db).await?;
+    for membership in channels {
+        if let Some(channel) = channel::Entity::find_by_id(membership.channel_id).filter(channel::Column::ChannelType.eq(channel::ChannelType::DM)).one(&state.db).await? {
+            let existing: HashSet<_> = member_ids(&state, channel.id).await?.into_iter().collect();
+            if existing == ids.iter().copied().collect() { return Ok(Json(response(&state, user.id, channel).await?)); }
+        }
+    }
+    let channel = create_channel(&state, &ids).await?;
+    Ok(Json(response(&state, user.id, channel).await?))
+}
+
+#[utoipa::path(post, path = "/conversations/{id}/fork", request_body = ForkConversationRequest, params(("id" = Uuid, Path)), responses((status = 200, body = ConversationResponse)), tag = "Conversations", security(("bearerAuth" = [])))]
+pub async fn fork(user: CurrentUser, State(state): State<AppState>, Path(id): Path<Uuid>, Json(payload): Json<ForkConversationRequest>) -> Result<Json<ConversationResponse>, HTTPError> {
+    let source = channel::Entity::find_by_id(id).one(&state.db).await?.ok_or(HTTPError::NotFound)?;
+    if source.channel_type != channel::ChannelType::DM || !member_ids(&state, id).await?.contains(&user.id) { return Err(HTTPError::Forbidden); }
+    let mut ids = member_ids(&state, id).await?;
+    ids.extend(payload.user_ids);
+    ids.sort_unstable(); ids.dedup();
+    validate_ids(&state, &ids).await?;
+    let channel = create_channel(&state, &ids).await?;
+    Ok(Json(response(&state, user.id, channel).await?))
+}

src/routes/conversation/mod.rs

@@ -0,0 +1,2 @@
+pub mod handlers;
+pub mod routes;

src/routes/conversation/routes.rs

@@ -0,0 +1,9 @@
+use super::handlers;
+use crate::core::state::AppState;
+use axum::{routing::{get, post}, Router};
+
+pub fn router() -> Router<AppState> {
+    Router::new()
+        .route("/conversations", get(handlers::list).post(handlers::create))
+        .route("/conversations/{id}/fork", post(handlers::fork))
+}