feat: schedule history — list, detail, rollback endpoints

k-tv-backend/api/src/routes/channels/mod.rs

@@ -27,6 +27,15 @@ pub fn router() -> Router<AppState> {
             "/{id}/schedule",
             post(schedule::generate_schedule).get(schedule::get_active_schedule),
         )
+        .route("/{id}/schedule/history", get(schedule::list_schedule_history))
+        .route(
+            "/{id}/schedule/history/{gen_id}",
+            get(schedule::get_schedule_history_entry),
+        )
+        .route(
+            "/{id}/schedule/history/{gen_id}/rollback",
+            post(schedule::rollback_schedule),
+        )
         .route("/{id}/now", get(broadcast::get_current_broadcast))
         .route("/{id}/epg", get(broadcast::get_epg))
         .route("/{id}/stream", get(broadcast::get_stream))

k-tv-backend/api/src/routes/channels/schedule.rs

@@ -10,7 +10,7 @@ use uuid::Uuid;
 use domain::{self, DomainError};
 
 use crate::{
-    dto::ScheduleResponse,
+    dto::{ScheduleHistoryEntry, ScheduleResponse},
     error::ApiError,
     extractors::CurrentUser,
     state::AppState,
@@ -60,3 +60,75 @@ pub(super) async fn get_active_schedule(
 
     Ok(Json(ScheduleResponse::from(schedule)))
 }
+
+/// List all schedule generations for a channel, newest first.
+/// Returns lightweight entries (no slots).
+pub(super) async fn list_schedule_history(
+    State(state): State<AppState>,
+    CurrentUser(user): CurrentUser,
+    Path(channel_id): Path<Uuid>,
+) -> Result<impl IntoResponse, ApiError> {
+    let channel = state.channel_service.find_by_id(channel_id).await?;
+    require_owner(&channel, user.id)?;
+
+    let history = state.schedule_engine.list_schedule_history(channel_id).await?;
+    let entries: Vec<ScheduleHistoryEntry> = history.into_iter().map(Into::into).collect();
+    Ok(Json(entries))
+}
+
+/// Fetch a single historical schedule with all its slots.
+pub(super) async fn get_schedule_history_entry(
+    State(state): State<AppState>,
+    CurrentUser(user): CurrentUser,
+    Path((channel_id, gen_id)): Path<(Uuid, Uuid)>,
+) -> Result<impl IntoResponse, ApiError> {
+    let channel = state.channel_service.find_by_id(channel_id).await?;
+    require_owner(&channel, user.id)?;
+
+    let schedule = state
+        .schedule_engine
+        .get_schedule_by_id(channel_id, gen_id)
+        .await?
+        .ok_or_else(|| ApiError::NotFound(format!("Schedule {} not found", gen_id)))?;
+
+    Ok(Json(ScheduleResponse::from(schedule)))
+}
+
+/// Roll back to a previous schedule generation.
+///
+/// Deletes all generations after `gen_id`'s generation, then generates a fresh
+/// schedule from now (inheriting the rolled-back generation as the base for
+/// recycle-policy history).
+pub(super) async fn rollback_schedule(
+    State(state): State<AppState>,
+    CurrentUser(user): CurrentUser,
+    Path((channel_id, gen_id)): Path<(Uuid, Uuid)>,
+) -> Result<impl IntoResponse, ApiError> {
+    let channel = state.channel_service.find_by_id(channel_id).await?;
+    require_owner(&channel, user.id)?;
+
+    let target = state
+        .schedule_engine
+        .get_schedule_by_id(channel_id, gen_id)
+        .await?
+        .ok_or_else(|| ApiError::NotFound(format!("Schedule {} not found", gen_id)))?;
+
+    state
+        .schedule_engine
+        .delete_schedules_after(channel_id, target.generation)
+        .await?;
+
+    let schedule = state
+        .schedule_engine
+        .generate_schedule(channel_id, Utc::now())
+        .await?;
+
+    let _ = state.event_tx.send(domain::DomainEvent::ScheduleGenerated {
+        channel_id,
+        schedule: schedule.clone(),
+    });
+    let detail = format!("rollback to gen {}; {} slots", target.generation, schedule.slots.len());
+    let _ = state.activity_log_repo.log("schedule_rollback", &detail, Some(channel_id)).await;
+
+    Ok((StatusCode::CREATED, Json(ScheduleResponse::from(schedule))))
+}