feat(phase-4): Backend API for custom workouts

- Add custom_workouts and custom_workout_exercises tables (schema) - New endpoints: - GET /api/exercises - List all exercises for picker - POST /api/custom-workouts - Fork program workout - GET /api/custom-workouts - List user's custom workouts - GET /api/custom-workouts/:id - Get workout with exercises - PUT /api/custom-workouts/:id - Update workout exercises - DELETE /api/custom-workouts/:id - Delete custom workout - Updated endpoints for source_type support: - GET /api/logs - Filter by source_type and custom_workout_id - POST /api/logs - Save with source_type and custom_workout_id - DELETE /api/logs - Support custom workout log deletion - Adds Phase 4 planning overview Completes: 04-01-schema-migration, 04-02-backend-api Next: 04-03-frontend-workout-edit
2026-03-01 03:36:53 +01:00
parent e488b5d86f
commit b2073b5d4c
7 changed files with 530 additions and 106 deletions
@@ -0,0 +1,85 @@
+# Phase 4: Workout Modification
+
+**Started:** 2026-03-01
+**Goal:** Let users customize program workouts by swapping or adding exercises, creating personal forks
+
+## Problem Statement
+
+Users want flexibility within their program structure. Currently:
+- Can't swap an exercise (e.g., replace bench press with dumbbell press due to equipment availability)
+- Can't add exercises to a program workout (e.g., add face pulls to Push day)
+- Any modification would require building a completely custom workout
+
+## Solution: Workout Forking
+
+When user modifies a program workout, we:
+1. Copy the program workout to `custom_workouts` table
+2. Store modifications in `custom_workout_exercises` table
+3. Save workout logs with `source_type = 'custom'` to track lineage
+4. Original program remains unchanged for future sessions
+
+## Phase Plans
+
+### 04-01: Database Schema Migration
+- Create `custom_workouts` table
+- Create `custom_workout_exercises` table
+- Add `source_type` enum column to `workout_logs`
+- Migration script with rollback
+
+### 04-02: Backend API for Custom Workouts
+- POST /api/custom-workouts (create from program workout)
+- PUT /api/custom-workouts/:id (update exercises)
+- GET /api/custom-workouts/:id (fetch with exercises)
+- GET /api/custom-workouts (list user's custom workouts)
+- Update workout log save to handle source_type
+
+### 04-03: Frontend - Workout Edit Mode
+- "Edit Workout" button on WorkoutSelectPage
+- Exercise picker modal/component
+- Swap exercise UI flow
+- Add exercise UI flow
+- Fork confirmation dialog
+
+## Success Criteria
+
+- [ ] User can replace any exercise in a program workout
+- [ ] User can add exercises to a program workout
+- [ ] Modified workout saves as custom_workout (original program unchanged)
+- [ ] Subsequent workout sessions use the forked custom workout
+- [ ] User can see which workouts are custom vs program originals
+
+## Database Schema
+
+```sql
+-- custom_workouts: Stores the forked workout header
+custom_workouts (
+  id SERIAL PRIMARY KEY,
+  user_id INTEGER REFERENCES users(id) ON DELETE CASCADE,
+  name VARCHAR(100) NOT NULL,
+  description TEXT,
+  original_program_day_id INTEGER REFERENCES program_days(id),
+  created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+-- custom_workout_exercises: Stores exercises in custom workout
+custom_workout_exercises (
+  id SERIAL PRIMARY KEY,
+  custom_workout_id INTEGER REFERENCES custom_workouts(id) ON DELETE CASCADE,
+  exercise_id INTEGER REFERENCES exercises(id) ON DELETE CASCADE,
+  set_order INTEGER NOT NULL,
+  sets INTEGER DEFAULT 3,
+  reps INTEGER DEFAULT 10,
+  weight_preset DECIMAL(5,2),
+  UNIQUE(custom_workout_id, set_order)
+);
+
+-- workout_logs.source_type: Tracks where log came from
+ALTER TABLE workout_logs ADD COLUMN source_type VARCHAR(20) DEFAULT 'program';
+-- Values: 'program', 'custom'
+```
+
+## Out of Scope
+
+- Building completely custom workouts from scratch (v2/CUS-01)
+- Reusable custom workout templates (v2/CUS-02)
+- Complex program modifications (reordering days, changing structure)