wire gap_filler into schedule engine, API, MCP

crates/domain/src/services/schedule/mod.rs

@@ -9,7 +9,8 @@ use crate::models::{
     ScheduledSlot,
 };
 use crate::ports::{ChannelQuery, LibraryQuery, ScheduleCommand, ScheduleQuery};
-use crate::value_objects::{BlockId, ChannelId, FillStrategy, InterstitialRule, LibrarySearchFilter, MediaItemId, MediaRole, RotationPolicy, Weekday};
+use crate::models::MediaItem;
+use crate::value_objects::{BlockId, ChannelId, FillStrategy, InterstitialRule, LibrarySearchFilter, MediaFilter, MediaItemId, MediaRole, RotationPolicy, Weekday};
 
 mod fill;
 mod rotation;
@@ -153,6 +154,13 @@ impl ScheduleEngineService {
 
         slots.sort_by_key(|s| s.start_at());
 
+        if let Some(gap_filter) = channel.gap_filler() {
+            let filler_items = self.query_gap_fillers(gap_filter).await?;
+            if !filler_items.is_empty() {
+                Self::fill_gaps(&mut slots, &filler_items, valid_from, valid_until);
+            }
+        }
+
         let schedule = GeneratedSchedule::new(
             channel_id,
             valid_from,
@@ -415,6 +423,71 @@ impl ScheduleEngineService {
 
         Ok(slots)
     }
+
+    async fn query_gap_fillers(&self, gap_filter: &MediaFilter) -> DomainResult<Vec<MediaItem>> {
+        let filter =
+            media_filter_to_library_search(gap_filter).with_role(MediaRole::Interstitial);
+        let (items, _) = self.library_query.search(&filter).await?;
+        Ok(items)
+    }
+
+    fn fill_gaps(
+        slots: &mut Vec<ScheduledSlot>,
+        fillers: &[MediaItem],
+        valid_from: DateTime<Utc>,
+        valid_until: DateTime<Utc>,
+    ) {
+        if fillers.is_empty() {
+            return;
+        }
+
+        let gap_block_id = BlockId::generate();
+        let mut gap_slots: Vec<ScheduledSlot> = Vec::new();
+        let mut filler_idx = 0usize;
+
+        let mut boundaries: Vec<(DateTime<Utc>, DateTime<Utc>)> = Vec::new();
+
+        if slots.is_empty() {
+            boundaries.push((valid_from, valid_until));
+        } else {
+            if slots[0].start_at() > valid_from {
+                boundaries.push((valid_from, slots[0].start_at()));
+            }
+            for pair in slots.windows(2) {
+                if pair[1].start_at() > pair[0].end_at() {
+                    boundaries.push((pair[0].end_at(), pair[1].start_at()));
+                }
+            }
+            if let Some(last) = slots.last() {
+                if last.end_at() < valid_until {
+                    boundaries.push((last.end_at(), valid_until));
+                }
+            }
+        }
+
+        for (gap_start, gap_end) in boundaries {
+            let mut cursor = gap_start;
+            while cursor < gap_end {
+                let filler = &fillers[filler_idx % fillers.len()];
+                let filler_end =
+                    (cursor + Duration::seconds(filler.duration_secs() as i64)).min(gap_end);
+                if filler_end <= cursor {
+                    break;
+                }
+                gap_slots.push(ScheduledSlot::new(
+                    cursor,
+                    filler_end,
+                    filler.clone(),
+                    gap_block_id,
+                ));
+                cursor = filler_end;
+                filler_idx += 1;
+            }
+        }
+
+        slots.append(&mut gap_slots);
+        slots.sort_by_key(|s| s.start_at());
+    }
 }
 
 fn media_filter_to_library_search(filter: &crate::value_objects::MediaFilter) -> LibrarySearchFilter {