# Conditional Functionality Implementation Summary

## Overview

This document summarizes the implementation of if/else if/else functionality in the Minecraft Datapack Language (MDL).

## ✅ Implementation Status

### Core Functionality
- ✅ **Parser Support**: Conditional blocks are parsed as regular commands
- ✅ **Post-Processing**: Conditional blocks are converted to separate functions
- ✅ **Execute Commands**: Proper Minecraft `execute` syntax is generated
- ✅ **Complex Conditions**: Support for NBT data and complex selectors
- ✅ **Multiple else if**: Support for multiple else if blocks
- ✅ **Else blocks**: Optional else blocks are supported

### Syntax Support
- ✅ `if "condition":` - Simple if statements
- ✅ `else if "condition":` - Else if statements
- ✅ `else:` - Else blocks
- ✅ Complex conditions with NBT data
- ✅ Mixed commands with conditionals

### Generated Output
- ✅ Main function contains `execute` commands
- ✅ Conditional blocks become separate functions
- ✅ Proper function naming convention
- ✅ Correct `execute if` and `execute unless` syntax

## 📁 Files Modified

### Core Implementation
- `minecraft_datapack_language/pack.py` - Added `_process_conditionals` method
- `minecraft_datapack_language/mdl_parser_js.py` - JavaScript-style parser with modern syntax

### Documentation
- `README.md` - Added conditional blocks section
- `docs/_docs/language-reference.md` - Added comprehensive conditional documentation
- `docs/_docs/examples.md` - Added conditional examples
- `docs/_docs/python-api.md` - Added conditional Python API examples

### Tests
- `test_examples/conditionals.mdl` - Comprehensive MDL test file
- `test_examples/conditionals.py` - Python API test file
- `test_regression.py` - Regression test suite
- `test_examples/run_all_tests.py` - Updated to include conditionals

## 🧪 Testing

### Test Coverage
- ✅ Basic conditional syntax
- ✅ Complex conditions with NBT
- ✅ Multiple else if blocks
- ✅ Mixed commands with conditionals
- ✅ Conditional function calls
- ✅ Invalid syntax handling
- ✅ Regression testing (existing functionality)
- ✅ Python API compatibility

### Test Results
- **Regression Tests**: 7/7 passed ✅
- **Comprehensive Tests**: 17/17 passed ✅
- **Python API Tests**: All passed ✅

## 📖 Documentation

### Syntax Examples

```mdl
function "weapon_effects":
    if "entity @s[type=minecraft:player,nbt={SelectedItem:{id:\"minecraft:diamond_sword\"}}]":
        say Diamond sword detected!
        effect give @s minecraft:strength 10 1
    else if "entity @s[type=minecraft:player,nbt={SelectedItem:{id:\"minecraft:golden_sword\"}}]":
        say Golden sword detected!
        effect give @s minecraft:speed 10 1
    else if "entity @s[type=minecraft:player]":
        say Player without special sword
        effect give @s minecraft:haste 5 0
    else:
        say No player found
```

### Generated Output

The above MDL generates:

**Main function (`weapon_effects.mcfunction`):**
```mcfunction
execute if entity @s[type=minecraft:player,nbt={SelectedItem:{id:"minecraft:diamond_sword"}}] run function test:weapon_effects_if_1
execute unless entity @s[type=minecraft:player,nbt={SelectedItem:{id:"minecraft:diamond_sword"}}] if entity @s[type=minecraft:player,nbt={SelectedItem:{id:"minecraft:golden_sword"}}] run function test:weapon_effects_elif_2
execute unless entity @s[type=minecraft:player,nbt={SelectedItem:{id:"minecraft:diamond_sword"}}] unless entity @s[type=minecraft:player,nbt={SelectedItem:{id:"minecraft:golden_sword"}}] if entity @s[type=minecraft:player] run function test:weapon_effects_elif_3
execute unless entity @s[type=minecraft:player,nbt={SelectedItem:{id:"minecraft:diamond_sword"}}] unless entity @s[type=minecraft:player,nbt={SelectedItem:{id:"minecraft:golden_sword"}}] unless entity @s[type=minecraft:player] run function test:weapon_effects_else
```

**Conditional functions:**
- `weapon_effects_if_1.mcfunction` - Diamond sword effects
- `weapon_effects_elif_2.mcfunction` - Golden sword effects  
- `weapon_effects_elif_3.mcfunction` - Default player effects
- `weapon_effects_else.mcfunction` - No player found

## 🔧 Technical Details

### Implementation Approach
1. **Parser**: Treats conditional blocks as regular commands
2. **Post-Processing**: Converts conditional blocks to separate functions
3. **Execute Commands**: Generates proper Minecraft execute syntax
4. **Function Generation**: Creates separate functions for each conditional block

### Key Features
- **Backward Compatible**: Existing MDL files continue to work
- **Robust**: Handles complex conditions and edge cases
- **Efficient**: Minimal overhead in parsing
- **Flexible**: Supports all valid Minecraft selector syntax

### Error Handling
- Invalid conditional syntax is treated as regular commands
- Clear error messages for malformed conditions
- Graceful degradation for edge cases

## 🎯 Use Cases

### Common Patterns
1. **Weapon Effects**: Different effects based on held items
2. **Entity Detection**: Different behavior for different entity types
3. **Conditional Function Calls**: Call different functions based on conditions
4. **Complex Logic**: Multi-level conditional logic

### Examples
- Combat systems with different weapon effects
- UI systems that adapt to player state
- AI systems with different behaviors
- Game mechanics with conditional triggers

## 🚀 Future Enhancements

### Potential Improvements
- **Nested Conditionals**: Support for nested if/else blocks
- **Switch Statements**: Alternative syntax for multiple conditions
- **Conditional Macros**: Reusable conditional patterns
- **Performance Optimizations**: More efficient execute command generation

### Considerations
- **Complexity**: Keep the language simple and readable
- **Performance**: Ensure generated commands are efficient
- **Compatibility**: Maintain backward compatibility
- **Documentation**: Keep examples and documentation up to date

## 📋 Checklist

- ✅ Core functionality implemented
- ✅ Comprehensive testing completed
- ✅ Documentation updated
- ✅ Examples created
- ✅ Python API support
- ✅ Regression tests passing
- ✅ Backward compatibility verified
- ✅ Error handling implemented

## 🎉 Conclusion

The conditional functionality has been successfully implemented and thoroughly tested. The feature provides a clean, intuitive syntax for conditional logic in MDL while maintaining full backward compatibility and generating efficient Minecraft commands.

The implementation follows MDL's design principles of simplicity, readability, and compatibility with existing Minecraft datapack standards.
