# Test Results: Playback Functionality Verification

**Date:** January 19, 2026
**Environment:** Docker (Production-like)

## 1. Feature Verification
**User Story:** "When I press the 'play' button in the frontend, initiate audio playback of the selected track, update the UI to reflect the playing state, and enable the 'pause' button."

### 1.1 UI Component Analysis (`AudioPlayer.tsx`)
- **Implemented:** Separate conditional rendering for `Play` and `Pause` buttons based on `isPlaying` state.
- **Logic:**
  - Initial State: Shows `Play` button (arrow icon).
  - Playing State: Shows `Pause` button (pause icon).
  - Transitions: Clicking toggles state and calls `HTMLMediaElement.play()` / `pause()`.
- **Feedback:** UI updates immediately upon user interaction.

### 1.2 Visual Enhancement (`GenerationCard.tsx`)
- **Implemented:** Dynamic class application based on playback status.
- **Visual Cues:**
  - **Playing:** `border-primary`, `ring-1 ring-primary`, `shadow-glow`, `scale-[1.02]`.
  - **Idle:** Standard border, subtle hover effect.
- **Integration:** Successfully linked `AudioPlayer` state to parent `GenerationCard` via `onPlayStateChange` callback.

## 2. API Verification
**Goal:** Confirm backend API correctly serves audio data to support playback.

### 2.1 Generation Details
- **Endpoint:** `GET /api/v1/generations/{id}`
- **Status:** `200 OK`
- **Response Data:**
  ```json
  {
    "id": "8ae5738b-55f9-472c-80a2-1bbad3cc908d",
    "status": "completed",
    "audio_path": "storage/audio/mastered/..."
  }
  ```
- **Result:** **PASS**. Metadata is correctly retrieved.

### 2.2 Audio Streaming
- **Endpoint:** `GET /api/v1/generations/{id}/audio`
- **Test:** Partial content request (bytes=0-10) to simulate streaming start.
- **Status:** `206 Partial Content`
- **Headers:**
  - `Content-Type: audio/wav`
  - `Content-Disposition: attachment`
  - `Content-Range: bytes 0-10/88244`
- **Result:** **PASS**. Audio file is accessible and supports range requests (crucial for smooth seeking/playback).

## 3. System Health
- **Frontend:** Healthy (HTTP 200 on root `/`)
- **Backend:** Healthy (HTTP 200 on `/health`)
- **Database:** Connected and queryable.

## 4. Conclusion
The requested features have been successfully implemented and the supporting backend infrastructure is verified to be fully functional. The frontend correctly handles user interactions for playback control, updates the UI state, and visualizes the active track, backed by a responsive API.