# Missing Backend API Data

This document outlines data that the frontend is ready to display but is not currently provided by the backend API. These features would enhance the match analysis experience.

## Round Winner & Win Reason

**Endpoint**: `GET /match/{id}/rounds`

**Currently Returns**:

```json
{
  "0": { "player_id": [bank, equipment, spent] },
  "1": { "player_id": [bank, equipment, spent] }
}
```

**Missing Fields Needed**:

| Field        | Type     | Description                            |
| ------------ | -------- | -------------------------------------- |
| `winner`     | `number` | Team ID that won the round (1=T, 2=CT) |
| `win_reason` | `string` | How the round ended                    |

**Win Reason Values**:

- `elimination` - All enemies killed
- `bomb_defused` - CT defused the bomb
- `bomb_exploded` - Bomb detonated successfully
- `time` - Round timer expired (CT win)
- `target_saved` - Hostage rescued (rare mode)

**Expected Response Format**:

```json
{
  "0": {
    "winner": 1,
    "win_reason": "elimination",
    "players": {
      "player_id": [bank, equipment, spent]
    }
  }
}
```

**Implementation**: Demo parser needs to capture `RoundEnd` game events and extract:

- `winner` field from the event
- `reason` field from the event

---

## Per-Round Player Stats

**Missing Fields per Player per Round**:

| Field              | Type     | Description                                  |
| ------------------ | -------- | -------------------------------------------- |
| `kills_in_round`   | `number` | Kills this player got in this specific round |
| `damage_in_round`  | `number` | Total damage dealt this round                |
| `assists_in_round` | `number` | Assists this round                           |

**Implementation**: During demo parse, aggregate `player_death` and `player_hurt` events per round, grouped by attacking player.

---

## Loss Bonus Tracking

**Missing Fields per Team per Round**:

| Field         | Type     | Description                    |
| ------------- | -------- | ------------------------------ |
| `loss_streak` | `number` | Consecutive round losses (0-4) |
| `loss_bonus`  | `number` | Current loss bonus amount      |

**CS2 Loss Bonus Scale**:
| Consecutive Losses | Bonus |
|-------------------|-------|
| 0 | $1,400 |
| 1 | $1,900 |
| 2 | $2,400 |
| 3 | $2,900 |
| 4+ | $3,400 |

**Implementation**: Track `RoundEnd` events and maintain loss counter per team, resetting on win.

---

## Frontend Readiness

The frontend already has:

- Type definitions for all missing fields (`src/lib/types/RoundStats.ts`)
- Zod validation schemas (`src/lib/schemas/roundStats.schema.ts`)
- UI components ready to display win reasons with icons
- Mock handlers showing expected data structure (`src/mocks/handlers/matches.ts`)

Once the backend provides this data, the frontend will automatically display it.

---

## Priority

1. **High**: Round winner & win reason - enables win/loss correlation analysis
2. **Medium**: Per-round player stats - enables round-by-round performance tracking
3. **Low**: Loss bonus tracking - nice-to-have for economy analysis