fix(infra): deserialize channel schedule_config via ScheduleConfigCompat for V1 compat

docs/superpowers/specs/2026-03-17-scheduling-v2-design.md

@@ -0,0 +1,284 @@
+# Scheduling V2 — Design Spec
+
+## Context
+
+The current scheduler is a 48h rolling window with a flat block list per channel. This works as MVP but has two major gaps for everyday use:
+
+1. **No weekly patterns** — users can't say "Monday runs X, weekends run Y"; all blocks repeat identically every day.
+2. **No history or recovery** — overwriting a channel config loses the previous setup forever; a bug that resets a sequential series (e.g. Sopranos resets from S3E4 to S1E1) has no recovery path.
+
+This spec covers two features: **weekly scheduling** and **schedule history**.
+
+---
+
+## Feature 1: Weekly Scheduling (7-day grid)
+
+### Data model
+
+`ScheduleConfig` changes from a flat block list to a day-keyed map:
+
+```rust
+// BEFORE
+pub struct ScheduleConfig {
+    pub blocks: Vec<ProgrammingBlock>,
+}
+
+// AFTER
+pub struct ScheduleConfig {
+    pub day_blocks: HashMap<Weekday, Vec<ProgrammingBlock>>,
+}
+
+pub enum Weekday {
+    Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday,
+}
+```
+
+`ProgrammingBlock` is otherwise unchanged. Block IDs remain UUIDs; each day has its own independent Vec, so the same "show" on Mon and Wed has two separate block entries (different IDs, independent continuity tracking).
+
+### Migration (transparent, zero-downtime)
+
+Existing `channels.schedule_config` stores `{"blocks":[...]}`. Use `#[serde(untagged)]` deserialization:
+
+```rust
+#[serde(untagged)]
+enum ScheduleConfigCompat {
+    V2(ScheduleConfig),       // {"day_blocks": {"monday": [...], ...}}
+    V1(OldScheduleConfig),    // {"blocks": [...]}
+}
+```
+
+V1→V2 conversion: clone the blocks Vec into all 7 days. The first `PUT /channels/:id` after deploy saves V2 format. Channels never touched continue to deserialize via V1 path indefinitely.
+
+**Edge case**: if a payload has both `blocks` and `day_blocks` keys (e.g. partially migrated export), `#[serde(untagged)]` tries V2 first and succeeds — `day_blocks` is used and `blocks` is silently ignored. This is acceptable; the alternative (error on ambiguity) would break more use cases.
+
+### ScheduleConfig helper methods
+
+Three methods on `ScheduleConfig` must be updated:
+
+- **`find_block_at(weekday: Weekday, time: NaiveTime) -> Option<&ProgrammingBlock>`** — searches `day_blocks[weekday]` for the block whose window contains `time`.
+- **`next_block_start_after(weekday: Weekday, time: NaiveTime) -> Option<NaiveTime>`** — searches that day's vec; returns `None` if no block starts after `time` on that day (day-rollover is the caller's responsibility).
+- **`earliest_block_start() -> Option<NaiveTime>`** — **iterates all days, returns the global earliest start time across the entire week**. This is the form needed by the background scheduler (which needs to know when any content starts). Empty day = no contribution; all days empty = `None`.
+
+**Call-site update pattern for `broadcast.rs` (lines 64, 171):**
+```rust
+// derive weekday from slot start_at in channel timezone
+let tz: chrono_tz::Tz = channel.timezone.parse().unwrap_or(chrono_tz::UTC);
+let local_dt = slot.start_at.with_timezone(&tz);
+let weekday = Weekday::from_chrono(local_dt.weekday()); // new From impl
+let block = channel.schedule_config.find_block_at(weekday, local_dt.time());
+```
+
+The same derivation applies to `dto.rs` (`ScheduledSlotResponse::with_block_access`).
+
+### MCP crate
+
+`mcp/src/tools/channels.rs` manipulates `schedule_config.blocks` directly. After V2:
+
+- The MCP `add_block` tool must accept a `day: Weekday` parameter (required). It pushes the new block to `day_blocks[day]`.
+- The MCP `remove_block` tool must iterate all days' vecs (remove by block ID across all days, since block IDs are unique per entry).
+- `mcp/src/server.rs` `set_schedule_config` must accept a `day_blocks` map. The old `blocks_json` string parameter is replaced with `day_blocks_json: String` (JSON object keyed by weekday name).
+
+These are breaking changes to the MCP API — acceptable since MCP tools are internal/developer-facing.
+
+### Generation engine
+
+- Window: `valid_from + 7 days` (was 48h). Update `GeneratedSchedule` doc comment accordingly.
+- Day iteration: already walks calendar days; now walks 7 days, looks up `day_blocks[weekday]` for each day.
+- **Empty day**: if `day_blocks[weekday]` is empty or the key is absent, that day produces no slots — valid, not an error.
+- Continuity (`find_last_slot_per_block`): unchanged.
+
+### Files changed (backend)
+- `domain/src/value_objects.rs` — add `Weekday` enum with `From<chrono::Weekday>` impl
+- `domain/src/entities.rs` — `ScheduleConfig`, `OldScheduleConfig` compat struct, update helper method signatures, update `GeneratedSchedule` doc comment
+- `domain/src/services.rs` — 7-day window, `day_blocks[weekday]` lookup per day
+- `api/src/routes/channels/broadcast.rs` — update block lookups at lines 64 and 171 using weekday-derivation pattern above
+- `api/src/dto.rs` — update `ScheduledSlotResponse::with_block_access` block lookup
+- `mcp/src/tools/channels.rs` — `add_block` accepts `day` param; `remove_block` iterates all days
+- `mcp/src/server.rs` — replace `blocks_json` with `day_blocks_json`
+
+---
+
+## Feature 2: Schedule History
+
+### 2a. Config version history
+
+Every `PUT /channels/:id` auto-snapshots the previous config before overwriting. Users can pin named checkpoints and restore any version.
+
+**New DB migration:**
+```sql
+CREATE TABLE channel_config_snapshots (
+    id          TEXT    PRIMARY KEY,
+    channel_id  TEXT    NOT NULL REFERENCES channels(id) ON DELETE CASCADE,
+    config_json TEXT    NOT NULL,
+    version_num INTEGER NOT NULL,
+    label       TEXT,               -- NULL = auto-saved, non-NULL = pinned
+    created_at  TEXT    NOT NULL,
+    UNIQUE (channel_id, version_num)
+);
+CREATE INDEX idx_config_snapshots_channel ON channel_config_snapshots(channel_id, version_num DESC);
+```
+
+**`version_num` assignment**: computed inside the write transaction as `SELECT COALESCE(MAX(version_num), 0) + 1 FROM channel_config_snapshots WHERE channel_id = ?`. The transaction serializes concurrent writes naturally in SQLite (single writer). The `UNIQUE` constraint is a safety net only — no 409 is exposed to the client; the server retries within the transaction if needed (in practice impossible with SQLite's serialized writes).
+
+**New API endpoints (all require auth + channel ownership — same auth middleware as existing channel routes):**
+```
+GET   /channels/:id/config/history
+      → [{id, version_num, label, created_at}]  -- channel_id omitted (implicit from URL)
+
+PATCH /channels/:id/config/history/:snap_id
+      body: {"label": "Before S3 switchover"}
+      → 404 if snap_id not found or not owned by this channel
+      → 200 {id, version_num, label, created_at}
+
+POST  /channels/:id/config/history/:snap_id/restore
+      → snapshots current config first, then replaces channel config with target snapshot
+      → 404 if snap_id not found or not owned by this channel
+      → 200 {channel}
+```
+
+**Domain + infra changes:**
+- `ChannelConfigSnapshot` entity (fields: id, channel_id, config, version_num, label, created_at)
+- Extend `ChannelRepository` port: `save_config_snapshot`, `list_config_snapshots`, `get_config_snapshot`, `patch_config_snapshot_label`
+- `ChannelService::update_channel` calls `save_config_snapshot` before writing new config
+
+**Files changed (backend):**
+- `domain/src/entities.rs` — add `ChannelConfigSnapshot`
+- `domain/src/repositories.rs` — extend `ChannelRepository` port
+- `infra/src/channel_repo.rs` — implement snapshot methods
+- `migrations_sqlite/YYYYMMDD_add_config_snapshots.sql`
+- `api/src/routes/channels.rs` — new history endpoints + DTOs for snapshot responses
+
+### 2b. Generated schedule audit log
+
+**Ownership check**: `get_schedule_by_id(channel_id, gen_id)` queries `generated_schedules WHERE id = :gen_id AND channel_id = :channel_id` — the `channel_id` column is the join, so no separate channel lookup is needed.
+
+**New API endpoints (all require auth + channel ownership):**
+```
+GET  /channels/:id/schedule/history
+     → [{id, generation, valid_from, valid_until}] ordered by generation DESC
+
+GET  /channels/:id/schedule/history/:gen_id
+     → full GeneratedSchedule with slots
+     → 404 if gen_id not found or channel_id mismatch
+
+POST /channels/:id/schedule/history/:gen_id/rollback
+     → 404 if gen_id not found or channel_id mismatch
+     → explicit two-step delete (no DB-level cascade from playback_records to generated_schedules):
+       1. DELETE FROM playback_records WHERE channel_id = ? AND generation > :target_generation
+       2. DELETE FROM generated_schedules WHERE channel_id = ? AND generation > :target_generation
+          (scheduled_slots cascade via FK from generated_schedules)
+     → calls generate_schedule from now
+     → 200 {new_schedule}
+```
+
+**Repository changes:**
+- `list_schedule_history(channel_id)` — headers only
+- `get_schedule_by_id(channel_id, gen_id)` — full with slots
+- `delete_schedules_after(channel_id, generation_num)` — two-step explicit delete as above
+
+**Files changed (backend):**
+- `domain/src/repositories.rs` — extend `ScheduleRepository`
+- `infra/src/schedule_repo.rs` — implement list, get-by-id, delete-after
+- `api/src/routes/channels.rs` — new history and rollback endpoints
+
+---
+
+## Frontend
+
+### Weekly grid editor (`edit-channel-sheet.tsx`)
+
+Replace the flat block list with a tabbed weekly grid:
+
+- 7 day tabs (Mon–Sun), each showing that day's block list
+- Blocks within a day: same card UI as current (drag to reorder, edit, delete)
+- "Copy to →" dropdown per tab: duplicates block entries with new UUIDs into target day(s)
+- "+ Add block for [Day]" button per tab
+- "🕐 Config history" button in sheet footer → opens config history panel
+
+### Config history panel (`config-history-sheet.tsx` — new)
+
+- List of snapshots: version_num, timestamp, label (if pinned)
+- Current version highlighted
+- Pin button on current version (opens label input)
+- Restore button on any past version (confirm dialog)
+
+### Schedule audit log (`schedule-history-dialog.tsx` — new)
+
+- Lists past generations: gen#, date range
+- "Rollback to here" button with confirm dialog
+
+### Types (`lib/types.ts`)
+```ts
+type Weekday = 'monday' | 'tuesday' | 'wednesday' | 'thursday' | 'friday' | 'saturday' | 'sunday'
+const WEEKDAYS: Weekday[] = ['monday','tuesday','wednesday','thursday','friday','saturday','sunday']
+
+interface ScheduleConfig {
+  day_blocks: Record<Weekday, ProgrammingBlock[]>
+}
+
+interface ConfigSnapshot {
+  id: string
+  version_num: number
+  label: string | null
+  created_at: string
+  // channel_id intentionally omitted — always accessed via /channels/:id/config/history
+}
+
+interface ScheduleHistoryEntry {
+  id: string
+  generation: number
+  valid_from: string
+  valid_until: string
+}
+```
+
+### Zod schema (`lib/schemas.ts`)
+```ts
+const weekdaySchema = z.enum(['monday','tuesday','wednesday','thursday','friday','saturday','sunday'])
+
+// replace blocks: z.array(blockSchema) with:
+day_blocks: z.record(weekdaySchema, z.array(blockSchema)).default(
+  () => Object.fromEntries(WEEKDAYS.map(d => [d, []])) as Record<Weekday, ProgrammingBlock[]>
+)
+// A missing day key is valid (treated as empty). The default initializes all days to [].
+```
+
+### Channel export (`lib/channel-export.ts`)
+Export format after V2: `day_blocks` map as-is (no flattening). The export JSON shape mirrors `ScheduleConfig` directly. Re-import reads via the same `ScheduleConfigCompat` deserialization path, so V1 exports remain importable indefinitely.
+
+### New hooks (`hooks/use-channels.ts`)
+- `useConfigHistory(channelId)`
+- `useRestoreConfig()`
+- `usePinSnapshot()`
+- `useScheduleHistory(channelId)`
+- `useScheduleGeneration(channelId, genId)` (lazy, for detail view)
+- `useRollbackSchedule()`
+
+### Files changed (frontend)
+- `lib/types.ts`
+- `lib/schemas.ts`
+- `lib/channel-export.ts`
+- `hooks/use-channels.ts`
+- `dashboard/components/edit-channel-sheet.tsx`
+- `dashboard/components/config-history-sheet.tsx` (new)
+- `dashboard/components/schedule-history-dialog.tsx` (new)
+- `app/(main)/dashboard/page.tsx` — wire new dialog triggers
+
+---
+
+## Verification
+
+| Scenario | Expected |
+|---|---|
+| Load channel with old `{blocks:[...]}` config | Blocks appear on all 7 day tabs |
+| `PUT /channels/:id` on old-format channel | Config saved as V2 `{day_blocks:{...}}`; snapshot v1 created |
+| Channel with Mon+Sat blocks only → generate | Slots only on Mondays and Saturdays in 7-day window |
+| Day with empty block list | No slots that day, no error |
+| `PUT /channels/:id` twice | `GET /config/history` returns 2 entries with incrementing version_num |
+| Pin snapshot | Label persists in history list |
+| Restore snapshot | Config reverts; new snapshot created at top of history |
+| `GET /schedule/history/:bad_id` | 404 |
+| Generate 3 schedules → rollback to gen#1 | gen#2+3 deleted (schedules + playback_records); new generation resumes from gen#1 continuity |
+| Sequential block at S4E2 → rollback → regenerate | New schedule starts at correct episode |
+| Payload with both `blocks` and `day_blocks` keys | `day_blocks` used, `blocks` silently ignored |
+| V1 export file re-imported after V2 deploy | Deserializes correctly via compat path |

k-tv-backend/Cargo.lock

@@ -702,6 +702,7 @@ dependencies = [
  "email_address",
  "rand 0.8.5",
  "serde",
+ "serde_json",
  "thiserror 2.0.17",
  "tokio",
  "url",

k-tv-backend/infra/src/channel_repository/mapping.rs

@@ -2,7 +2,7 @@ use chrono::{DateTime, Utc};
 use sqlx::FromRow;
 use uuid::Uuid;
 
-use domain::{AccessMode, Channel, ChannelId, DomainError, LogoPosition, RecyclePolicy, ScheduleConfig, UserId};
+use domain::{AccessMode, Channel, ChannelId, DomainError, LogoPosition, RecyclePolicy, ScheduleConfig, ScheduleConfigCompat, UserId};
 
 #[derive(Debug, FromRow)]
 pub(super) struct ChannelRow {
@@ -44,10 +44,11 @@ impl TryFrom<ChannelRow> for Channel {
             .map_err(|e| DomainError::RepositoryError(format!("Invalid channel UUID: {}", e)))?;
         let owner_id: UserId = Uuid::parse_str(&row.owner_id)
             .map_err(|e| DomainError::RepositoryError(format!("Invalid owner UUID: {}", e)))?;
-        let schedule_config: ScheduleConfig = serde_json::from_str(&row.schedule_config)
+        let schedule_config: ScheduleConfig = serde_json::from_str::<ScheduleConfigCompat>(&row.schedule_config)
             .map_err(|e| {
                 DomainError::RepositoryError(format!("Invalid schedule_config JSON: {}", e))
-            })?;
+            })
+            .map(ScheduleConfig::from)?;
         let recycle_policy: RecyclePolicy = serde_json::from_str(&row.recycle_policy)
             .map_err(|e| {
                 DomainError::RepositoryError(format!("Invalid recycle_policy JSON: {}", e))