"""
Ritz Debugging Infrastructure Concept
Shows how we can debug Python code running in WASM
"""

import json
from dataclasses import dataclass
from typing import Dict, List, Optional

@dataclass
class DebugSymbol:
    """Maps WASM offset to Python source location"""
    wasm_offset: int
    file: str
    line: int
    column: int
    function: str
    source_text: str

class WASMDebugger:
    """Debugging infrastructure for Python-in-WASM"""
    
    def __init__(self):
        self.symbols: Dict[int, DebugSymbol] = {}
        self.breakpoints: List[DebugSymbol] = []
        self.source_files: Dict[str, List[str]] = {}
    
    def generate_debug_info(self, component_ir, wasm_module):
        """Generate debug symbols during compilation"""
        # This would be done by LLVM during compilation
        # Here's a conceptual example:
        
        debug_info = {
            'format': 'ritz-debug-v1',
            'source_language': 'python',
            'symbols': []
        }
        
        # Map each IR node to WASM offsets
        for node in component_ir['body']:
            if node['type'] == 'yield':
                symbol = {
                    'wasm_offset': '0x1234',  # Would be actual WASM offset
                    'source': {
                        'file': 'component.py',
                        'line': node.get('line', 0),
                        'column': node.get('column', 0),
                        'text': 'yield Element()'
                    }
                }
                debug_info['symbols'].append(symbol)
        
        return debug_info
    
    def set_breakpoint(self, file: str, line: int):
        """Set a breakpoint at Python source location"""
        # Find WASM offset for this source location
        for offset, symbol in self.symbols.items():
            if symbol.file == file and symbol.line == line:
                print(f"Breakpoint set at {file}:{line} (WASM offset: {hex(offset)})")
                self.breakpoints.append(symbol)
                
                # In real implementation, this would:
                # 1. Communicate with browser DevTools
                # 2. Set WASM breakpoint at the offset
                # 3. Map back to Python source when hit
                return True
        
        return False
    
    def source_map_example(self):
        """Example of source map for WASM→Python mapping"""
        source_map = {
            "version": 3,
            "sources": ["counter.py", "framework.py"],
            "names": ["count", "increment", "signal"],
            "mappings": "AAAA,SAAS;AACT,YAAY",  # Base64 VLQ encoded
            "file": "app.wasm",
            
            # Extensions for Python debugging
            "x_ritz_debug": {
                "python_version": "3.11",
                "symbols": [
                    {
                        "wasm_offset": "0x1000",
                        "python_location": "counter.py:5:8",
                        "ast_node": "ast.Assign",
                        "scope_vars": ["count", "increment"]
                    }
                ],
                
                # Embedded Python source for debugging!
                "embedded_sources": {
                    "counter.py": """
@component
def Counter():
    count = signal(0)  # Line 3
    
    def increment():   # Line 5
        count += 1     # Line 6 - Breakpoint here!
    
    with Div():
        yield Button('Click', onclick=increment)
                    """
                }
            }
        }
        
        return source_map

class LiveEditingSupport:
    """Live editing Python components in the browser"""
    
    def __init__(self, debugger: WASMDebugger):
        self.debugger = debugger
        self.module_cache = {}
    
    def edit_component(self, component_name: str, new_source: str):
        """Live edit a component"""
        print(f"Live editing {component_name}")
        
        # 1. Parse the new Python source
        from ast_parser import parse_component_source
        ir = parse_component_source(new_source)
        
        # 2. Compile just this component to WASM
        wasm_module = self.compile_component(ir)
        
        # 3. Hot reload in browser
        self.hot_reload(component_name, wasm_module)
        
        return {
            'status': 'reloaded',
            'component': component_name,
            'size': len(wasm_module)
        }
    
    def compile_component(self, ir):
        """Compile single component to WASM module"""
        # In reality, this would use LLVM
        # For now, mock it
        return b'\x00asm\x01\x00\x00\x00...'
    
    def hot_reload(self, name: str, wasm_bytes: bytes):
        """Hot reload a WASM module in browser"""
        js_code = f"""
        // Hot reload component
        const oldModule = RitzModules.get('{name}');
        const newModule = await WebAssembly.instantiate({list(wasm_bytes)});
        
        // Preserve state
        const state = oldModule.exports.get_state();
        newModule.exports.set_state(state);
        
        // Swap modules
        RitzModules.set('{name}', newModule);
        
        // Re-render affected components
        RitzRenderer.rerender('{name}');
        """
        print(f"Hot reload JS:\n{js_code}")

class BrowserDevToolsIntegration:
    """Integration with Chrome/Firefox DevTools"""
    
    @staticmethod
    def generate_dwarf_symbols():
        """Generate DWARF debug symbols for WASM"""
        # DWARF is the standard debug format
        # LLVM can generate this automatically
        
        dwarf = {
            '.debug_info': {
                'compilation_unit': {
                    'language': 'DW_LANG_Python',
                    'producer': 'Ritz Compiler v0.1',
                    'source_file': 'app.py'
                }
            },
            '.debug_line': {
                # Line number program
                # Maps WASM addresses to source lines
                'line_table': [
                    {'address': 0x1000, 'file': 1, 'line': 5, 'column': 8},
                    {'address': 0x1010, 'file': 1, 'line': 6, 'column': 4},
                ]
            },
            '.debug_abbrev': {
                # Abbreviation table
            }
        }
        
        return dwarf
    
    @staticmethod
    def devtools_protocol_example():
        """Example of Chrome DevTools Protocol for WASM debugging"""
        return {
            'method': 'Debugger.setBreakpoint',
            'params': {
                'location': {
                    'scriptId': 'wasm://app.wasm/counter.py',
                    'lineNumber': 6,
                    'columnNumber': 8
                }
            }
        }

# Demonstration
if __name__ == '__main__':
    print("=== Ritz Debugging Infrastructure ===\n")
    
    debugger = WASMDebugger()
    
    print("1. Source Map Example:")
    print(json.dumps(debugger.source_map_example(), indent=2)[:500] + "...\n")
    
    print("2. Setting Breakpoint:")
    # Simulate adding debug symbols
    debugger.symbols[0x1234] = DebugSymbol(
        wasm_offset=0x1234,
        file='counter.py',
        line=6,
        column=8,
        function='increment',
        source_text='count += 1'
    )
    debugger.set_breakpoint('counter.py', 6)
    
    print("\n3. Live Editing:")
    editor = LiveEditingSupport(debugger)
    result = editor.edit_component('Counter', '''
@component
def Counter():
    count = signal(0)
    
    def increment():
        count += 2  # Changed from += 1
        print(f"New count: {count}")
    
    with Div():
        yield Button('Click', onclick=increment)
    ''')
    print(f"Result: {result}")
    
    print("\n4. DevTools Integration:")
    print(json.dumps(BrowserDevToolsIntegration.devtools_protocol_example(), indent=2))
    
    print("\n=== The Dream ===")
    print("""
    In Chrome DevTools:
    - Set breakpoints in Python source (not WASM or JS!)
    - Step through Python code line by line
    - Inspect Python variables and objects
    - Live edit Python and see changes immediately
    - Full stack traces in Python
    
    This is possible because:
    1. Our Python compiles to WASM with debug symbols
    2. WASM has source map support
    3. We embed Python source in the WASM module
    4. Browser DevTools understand DWARF/source maps
    """)