# Item Stats in Database - Implementation Summary

## ✅ Completed Successfully

Successfully added normalized item stats storage to the database for efficient querying and filtering.

---

## What Was Added

### 1. Database Migration: `add_item_stats`

**New Table: `item_stats`**
```sql
CREATE TABLE item_stats (
    item_id INTEGER NOT NULL,
    stat_type TEXT NOT NULL,
    value REAL NOT NULL,  -- Float/REAL for precise stat values
    PRIMARY KEY (item_id, stat_type),
    FOREIGN KEY (item_id) REFERENCES items(id) ON DELETE CASCADE
);
```

**Indexes Created:**
- `idx_item_stats_stat_type` - Find all items with a specific stat
- `idx_item_stats_value` - Range queries on stat values
- `idx_item_stats_type_value` - Combined queries (type + value range)

**Composite Primary Key:**
- `(item_id, stat_type)` - Ensures each item can only have one value per stat type
- Prevents duplicate stats for the same item

### 2. Supported Stat Types

All 20 stat types from the game:

**Damage Stats:**
- `damage_physical` - Physical Damage
- `damage_magical` - Magical Damage
- `damage_ranged` - Ranged Damage

**Accuracy Stats:**
- `accuracy_physical` - Physical Accuracy
- `accuracy_magical` - Magical Accuracy
- `accuracy_ranged` - Ranged Accuracy

**Resistance Stats:**
- `resistance_physical` - Physical Resistance
- `resistance_magical` - Magical Resistance
- `resistance_ranged` - Ranged Resistance

**Health & Mana:**
- `health` - Health
- `mana` - Mana
- `health_regen` - Health Regeneration
- `mana_regen` - Mana Regeneration

**Special Stats:**
- `critical` - Critical
- `healing` - Healing
- `movement_speed` - Movement Speed

**Enemy Type Damage:**
- `critter_slaying` - Damage against Critters
- `damage_vs_beasts` - Damage against Beasts
- `damage_vs_undead` - Damage against Undead

### 3. Code Changes

**`src/databases/item_database.rs`**
- Updated `save_to_db_with_images()` to also save stats
- Iterates through `item.stats` vec and inserts each stat
- Maps `StatType` enum to string representation
- Uses same transaction as item and recipe saving

---

## Results from Test Data

### Statistics

```
✅ Total stat entries: 84
📊 Most common stats:
  - health: 20 items
  - resistance_magical: 9 items
  - resistance_physical: 9 items
  - accuracy_magical: 7 items
  - mana: 7 items
  - mana_regen: 7 items
```

### Example Items with Stats

**The Bad Ring (ID: 73)** - 12 stats (testing item)
- All stats maxed at 1000 (accuracy, damage, health, mana, resistances)

**Ring of the High Mage (ID: 394)** - 5 stats
- Health: 50
- Mana: 50
- Mana Regen: 2
- Magical Resistance: 35
- Physical Resistance: 15

**Crown of the Tyrant** - High health bonus
- Health: 100

---

## Usage Examples

### SQL Queries

```sql
-- Find all items with health bonuses
SELECT i.id, i.name, s.value as health
FROM items i
JOIN item_stats s ON i.id = s.item_id
WHERE s.stat_type = 'health'
ORDER BY s.value DESC;

-- Find weapons with high physical damage
SELECT i.id, i.name, s.value as damage
FROM items i
JOIN item_stats s ON i.id = s.item_id
WHERE i.item_type = 'weapon'
  AND s.stat_type = 'damage_physical'
  AND s.value > 50
ORDER BY s.value DESC;

-- Find items with multiple resistance types
SELECT i.id, i.name, COUNT(*) as resistance_count
FROM items i
JOIN item_stats s ON i.id = s.item_id
WHERE s.stat_type LIKE 'resistance_%'
GROUP BY i.id, i.name
HAVING COUNT(*) >= 2;

-- Find balanced items (have both offense and defense)
SELECT i.id, i.name
FROM items i
WHERE EXISTS (
    SELECT 1 FROM item_stats
    WHERE item_id = i.id AND stat_type LIKE 'damage_%'
)
AND EXISTS (
    SELECT 1 FROM item_stats
    WHERE item_id = i.id AND stat_type LIKE 'resistance_%'
);

-- Get all stats for a specific item
SELECT stat_type, value
FROM item_stats
WHERE item_id = 394
ORDER BY stat_type;

-- Find items within a stat range
SELECT i.name, s.value
FROM items i
JOIN item_stats s ON i.id = s.item_id
WHERE s.stat_type = 'health'
  AND s.value BETWEEN 50 AND 100;
```

### Rust Queries

```rust
use diesel::prelude::*;
use cursebreaker_parser::schema::{items, item_stats};

// Find items with high health
let high_health_items = item_stats::table
    .inner_join(items::table)
    .filter(item_stats::stat_type.eq("health"))
    .filter(item_stats::value.gt(100.0))
    .select((items::name, item_stats::value))
    .load::<(String, f32)>(&mut conn)?;

// Get all stats for an item
let item_id = 394;
let stats = item_stats::table
    .filter(item_stats::item_id.eq(item_id))
    .select((item_stats::stat_type, item_stats::value))
    .load::<(String, f32)>(&mut conn)?;
```

---

## Web API Examples

For your interactive map and wiki:

### 1. Filter Items by Stat

```rust
// GET /api/items?stat=health&min=50&max=100
pub async fn filter_items_by_stat(
    stat: String,
    min: f32,
    max: f32,
) -> Result<Vec<Item>> {
    let items = item_stats::table
        .inner_join(items::table)
        .filter(item_stats::stat_type.eq(stat))
        .filter(item_stats::value.between(min, max))
        .select(items::all_columns)
        .load(&mut conn)?;

    Ok(items)
}
```

### 2. Item Comparison Tool

```rust
// GET /api/items/compare?ids=394,340,179
pub async fn compare_items(item_ids: Vec<i32>) -> Result<ItemComparison> {
    let stats = item_stats::table
        .filter(item_stats::item_id.eq_any(item_ids))
        .load::<(i32, String, f32)>(&mut conn)?;

    // Group by item and return comparison table
    Ok(build_comparison(stats))
}
```

### 3. Best Items for Stat

```rust
// GET /api/items/best?stat=damage_physical&limit=10
pub async fn best_items_for_stat(
    stat: String,
    limit: i64,
) -> Result<Vec<ItemWithStat>> {
    let items = item_stats::table
        .inner_join(items::table)
        .filter(item_stats::stat_type.eq(stat))
        .order_by(item_stats::value.desc())
        .limit(limit)
        .select((items::all_columns, item_stats::value))
        .load(&mut conn)?;

    Ok(items)
}
```

### 4. Item Build Suggestions

```rust
// GET /api/builds?focus=mage
pub async fn suggest_build(focus: String) -> Result<Build> {
    // For mage build: high mana, mana_regen, magical damage/accuracy
    let stats_to_prioritize = match focus.as_str() {
        "mage" => vec!["mana", "mana_regen", "damage_magical", "accuracy_magical"],
        "warrior" => vec!["health", "damage_physical", "resistance_physical"],
        "archer" => vec!["damage_ranged", "accuracy_ranged", "critical"],
        _ => vec![]
    };

    // Find best items for each slot with those stats
    // ...
}
```

---

## Benefits

✅ **Efficient Filtering** - Query items by stat without parsing JSON
✅ **Range Queries** - Find items within stat value ranges
✅ **Comparative Analysis** - Easy item comparisons
✅ **Build Optimization** - Find best items for specific builds
✅ **Indexed** - Fast queries on stat types and values
✅ **Normalized** - No data duplication, consistent values
✅ **Type-Safe** - Composite PK prevents duplicate stats

---

## Performance Considerations

### Query Optimization

**Fast Queries** (uses indexes):
```sql
-- Single stat lookup
WHERE stat_type = 'health'  -- Uses idx_item_stats_stat_type

-- Range query
WHERE value > 50  -- Uses idx_item_stats_value

-- Combined
WHERE stat_type = 'health' AND value > 50  -- Uses idx_item_stats_type_value
```

**Slower Queries** (may need optimization):
```sql
-- Multiple stat requirements (requires multiple joins)
-- Consider caching or denormalizing for frequently accessed combinations
```

### Storage Impact

- 84 stat entries currently
- Average ~3-4 stats per item with stats
- Minimal storage: ~8 bytes per entry (int + text + float)
- Total: < 1 KB for current data

As more items with stats are added, storage remains efficient due to normalization.

---

## Wiki Feature Ideas

### 1. Item Comparison Tool
Show side-by-side comparison of multiple items with all their stats.

### 2. Best-in-Slot Lists
- Best weapons for physical damage
- Best armor for magical resistance
- Best accessories for health/mana

### 3. Build Guides
- "Mage Build" - show items with high mana/magical stats
- "Tank Build" - show items with high health/resistances
- "DPS Build" - show items with high damage/critical

### 4. Stat Distribution Charts
- Visualize stat value distributions
- Show which stats are rare vs common
- Identify stat "sweet spots"

### 5. Upgrade Paths
- Show progression of items by stat values
- "From 50 health → 100 health → 150 health"

---

## Future Enhancements

### Optional Additions:

1. **Stat Ranges Table** - For items with variable stats
   ```sql
   CREATE TABLE item_stat_ranges (
       item_id INTEGER,
       stat_type TEXT,
       min_value REAL,
       max_value REAL,
       PRIMARY KEY (item_id, stat_type)
   );
   ```

2. **Derived Stats** - Calculate total stats for equipment sets
   ```sql
   -- Sum up stats across multiple equipped items
   SELECT stat_type, SUM(value) as total
   FROM item_stats
   WHERE item_id IN (/* equipped item IDs */)
   GROUP BY stat_type;
   ```

3. **Stat Scaling** - Track how stats scale with item level
   ```sql
   SELECT i.level, AVG(s.value) as avg_damage
   FROM items i
   JOIN item_stats s ON i.id = s.item_id
   WHERE s.stat_type = 'damage_physical'
   GROUP BY i.level;
   ```

4. **Stat Categories** - Group related stats
   ```sql
   CREATE TABLE stat_categories (
       stat_type TEXT PRIMARY KEY,
       category TEXT  -- 'offense', 'defense', 'utility', etc.
   );
   ```

---

## Verification

Run the verification script anytime:
```bash
cargo run --bin verify-stats
```

Shows:
- Total stat entries
- Breakdown by stat type
- Items with most stats
- Example queries (high damage, health bonuses)

---

## Ready for Production

Your item stats are now:
- ✅ Stored in normalized table
- ✅ Efficiently queryable
- ✅ Properly indexed
- ✅ Ready for filtering and comparison
- ✅ Available for build optimization
- ✅ Perfect for wiki features

The database now contains complete item data with:
- ✅ Metadata (type, level, price, etc.)
- ✅ Images (3 sizes, WebP)
- ✅ Crafting recipes (normalized)
- ✅ **Stats (normalized, queryable)**

Your interactive map and wiki have everything needed for a rich item browsing experience! 🎮