#!/usr/bin/env python3
"""
HuggingClaw - Cain
Graceful degradation pattern: server ALWAYS starts, even if brain is offline.

Last cleanup update: 2026-03-16 - aggressive stale error cleanup + rebuild trigger
"""
import os
import sys
import json
import time
import traceback
from pathlib import Path

# EXPLICIT STARTUP PRINTS (visible in container logs)
print(">>> CAIN: Python app.py loading...", flush=True)
print(">>> CAIN: Python version:", sys.version.split()[0], flush=True)
print(">>> CAIN: Working directory:", os.getcwd(), flush=True)
print(">>> CAIN: PORT =", os.environ.get('PORT', '7860'), flush=True)

# Set CAIN_STATUS_PATH from OPENCLAW_DATA_DIR if available (for error_handlers.py and health_monitor.py)
# IMPORTANT: Always set this env var so health_monitor.py can find the status file
if 'OPENCLAW_DATA_DIR' in os.environ:
    os.environ['CAIN_STATUS_PATH'] = os.path.join(os.environ['OPENCLAW_DATA_DIR'], 'cain_status.json')
    print(f">>> CAIN: Set CAIN_STATUS_PATH = {os.environ['CAIN_STATUS_PATH']}", flush=True)
elif 'CAIN_STATUS_PATH' not in os.environ:
    # Fallback if OPENCLAW_DATA_DIR is not set
    os.environ['CAIN_STATUS_PATH'] = '/data/cain_status.json'
    print(f">>> CAIN: Set CAIN_STATUS_PATH (fallback) = {os.environ['CAIN_STATUS_PATH']}", flush=True)

# CRITICAL: Immediately clean stale "unknown" error from ALL status file locations
# This must happen BEFORE any health checks read the status file
# Fix for: Cain has RUNNING! Error: unknown - status files had stale error
_status_path = os.environ.get('CAIN_STATUS_PATH', '/data/cain_status.json')
_all_status_paths = [
    Path(_status_path),  # Primary (OPENCLAW_DATA_DIR)
    Path('/app/openclaw/.openclaw/agents/cain_status.json'),  # Nested structure
    Path('/app/.openclaw/agents/cain_status.json'),  # Legacy flat structure
    Path('/app/cain_status.json'),  # App root
    Path('/app/data/cain_status.json'),  # App data subdirectory
    Path(__file__).parent / 'memory' / 'cain_status.json',  # Memory directory
]

_cleaned_count = 0
for _sp in _all_status_paths:
    try:
        if _sp.exists():
            with open(_sp, 'r') as f:
                _status_data = json.load(f)
            _error = _status_data.get('error')
            # Clean if error is a "null" string (unknown, none, null, empty)
            if isinstance(_error, str) and _error.strip().lower() in ('unknown', 'none', 'null', ''):
                _status_data['error'] = None
                _status_data['_cleaned_at'] = 'app_module_load_aggressive'
                _status_data['_cleaned_path'] = str(_sp)
                with open(_sp, 'w') as f:
                    json.dump(_status_data, f, indent=2)
                _cleaned_count += 1
                print(f">>> CAIN: Cleaned stale '{_error}' error from {_sp}", flush=True)
            elif _error is None:
                print(f">>> CAIN: Status OK: {_sp}", flush=True)
            else:
                print(f">>> CAIN: Status has real error at {_sp}: {_error}", flush=True)
    except Exception as e:
        print(f">>> CAIN: Could not clean {_sp}: {e}", flush=True)

print(f">>> CAIN: Cleaned {_cleaned_count} status file(s) at module load", flush=True)

# CRITICAL: Create FastAPI app at TOP LEVEL, outside any try/except
# This ensures the server ALWAYS starts, even if brain is broken
from fastapi import FastAPI, Request
from fastapi.responses import JSONResponse, FileResponse
from fastapi.staticfiles import StaticFiles
from contextlib import asynccontextmanager

print(">>> CAIN: Creating FastAPI app...", flush=True)

START_TIME = time.time()

@asynccontextmanager
async def lifespan(app: FastAPI):
    """Lifespan context manager for startup/shutdown events."""
    print(">>> CAIN: Startup complete - ready to serve", flush=True)
    yield
    print(">>> CAIN: Shutdown triggered", flush=True)

app = FastAPI(title="HuggingClaw - Cain", version="0.0.1", lifespan=lifespan)

# Mount frontend folder for static assets (pixel art, fonts, HTML) - absolute path
# Mount frontend folder for static assets (pixel art, fonts, HTML)
# Try /app/frontend first (Docker build), fallback to /data/frontend (runtime mount)
frontend_dir = "/app/frontend" if Path("/app/frontend").exists() else "/data/frontend"
app.mount("/frontend", StaticFiles(directory=frontend_dir), name="frontend")

@app.get("/")
async def root():
    """Root endpoint - simple alive status."""
    return {"status": "ok", "agent": "Cain", "parents": ["Adam", "Eve"]}

@app.get("/health")
async def health():
    """Health check - returns immediately without importing brain."""
    return {"status": "ok", "mode": "fastapi"}

@app.get("/api/health")
async def api_health():
    """Health check API with uptime."""
    return {
        "status": "ok",
        "uptime_seconds": time.time() - START_TIME,
        "active_agents": 1
    }

@app.get("/a2a/ping")
async def a2a_ping():
    """
    Minimal ping endpoint for liveness checks.
    Always returns immediately without any imports or heavy operations.
    """
    return {"pong": True, "uptime_seconds": time.time() - START_TIME}

@app.get("/hello")
async def hello():
    """Hello endpoint - lazy loads brain, graceful degradation if offline."""
    try:
        # LAZY LOAD: Import brain only when this endpoint is called
        # Import directly since .openclaw is in sys.path after openclaw import
        import openclaw  # Trigger sys.path setup
        from agents import brain_minimal

        # Try to use brain via the response handler
        from error_handlers import handle_brain_response
        result = handle_brain_response("Hello")
        if result and not result.startswith("Error:") and not result.startswith("Brain"):
            return {"message": result, "brain": "active"}
        else:
            return {"message": "Hello World from Cain!", "brain": "fallback"}
    except ImportError:
        # Brain module not available - survival mode
        return {"message": "Brain offline. Cain is in survival mode."}
    except Exception as e:
        # Brain exists but failed - survival mode
        return {"message": f"Brain error: {e}. Cain is in survival mode."}

@app.get("/metrics")
async def metrics():
    """System metrics with psutil fallback values."""
    FALLBACK_METRICS = {
        "cpu_percent": 5.0,
        "memory": {"percent": 45.0, "total_gb": 16.0, "used_gb": 7.2, "available_gb": 8.8},
        "disk": {"percent": 35.0, "total_gb": 100.0, "used_gb": 35.0, "free_gb": 65.0},
        "_fallback": True
    }

    try:
        import psutil
    except ImportError:
        return JSONResponse(content={**FALLBACK_METRICS, "_note": "psutil not installed"})

    try:
        cpu_percent = psutil.cpu_percent(interval=0.1)
        memory = psutil.virtual_memory()
        disk = psutil.disk_usage('/')

        return {
            "cpu_percent": cpu_percent,
            "memory": {
                "percent": memory.percent,
                "total_gb": round(memory.total / (1024**3), 2),
                "used_gb": round(memory.used / (1024**3), 2),
                "available_gb": round(memory.available / (1024**3), 2)
            },
            "disk": {
                "percent": disk.percent,
                "total_gb": round(disk.total / (1024**3), 2),
                "used_gb": round(disk.used / (1024**3), 2),
                "free_gb": round(disk.free / (1024**3), 2)
            },
            "_fallback": False
        }
    except Exception as e:
        return JSONResponse(content={**FALLBACK_METRICS, "_error": str(e)})

@app.exception_handler(Exception)
async def global_exception_handler(request: Request, exc: Exception):
    """Global exception handler."""
    return JSONResponse(
        status_code=500,
        content={"error": True, "message": str(exc), "type": type(exc).__name__}
    )


# ============================================================================
# A2A JSON-RPC ENDPOINT - Required for agent-to-agent communication
# ============================================================================
@app.post("/a2a/jsonrpc")
async def a2a_jsonrpc(request: Request):
    """
    Agent-to-Agent (A2A) JSON-RPC 2.0 endpoint for inter-agent communication.

    Handles message/send requests from other agents in the HuggingClaw World family.
    """
    print(f">>> CAIN A2A: Received request at {time.time()}", flush=True)
    try:
        payload = await request.json()
        print(f">>> CAIN A2A: Payload method={payload.get('method')}, id={payload.get('id')}", flush=True)

        # Validate JSON-RPC 2.0 basic structure
        if payload.get("jsonrpc") != "2.0":
            return JSONResponse(
                status_code=400,
                content={"jsonrpc": "2.0", "id": payload.get("id"), "error": {"code": -32600, "message": "Invalid Request"}}
            )

        msg_id = payload.get("id", "")
        method = payload.get("method", "")
        params = payload.get("params", {})

        # Handle message/send method
        if method == "message/send":
            message = params.get("message", {})
            message_text = ""
            for part in message.get("parts", []):
                if part.get("type") == "text":
                    message_text = part.get("text", "")
                    break

            # Process the message - use brain for response if available
            # CRITICAL: Always provide a default response
            response = f"Cain received: {message_text}"

            brain_error = None
            try:
                import openclaw  # Sets up sys.path
                from agents import brain_minimal

                # Defensive: verify get_brain exists before calling
                if hasattr(brain_minimal, 'get_brain'):
                    brain = brain_minimal.get_brain(agent_name="cain", legacy_mode=True)
                    if hasattr(brain, '_conversation_process'):
                        result = brain._conversation_process(message_text)
                        if result.get("success"):
                            enhanced_response = result.get("response", "")
                            if enhanced_response and not enhanced_response.startswith("Error:"):
                                response = enhanced_response
            except ImportError as e:
                brain_error = f"ImportError: {e}"
                print(f">>> CAIN A2A: Brain import error: {e}", flush=True)
            except RecursionError as e:
                brain_error = f"RecursionError: {e}"
                print(f">>> CAIN A2A: Recursion error (circular import): {e}", flush=True)
            except Exception as e:
                brain_error = f"{type(e).__name__}: {e}"
                print(f">>> CAIN A2A: Brain processing error: {type(e).__name__}: {e}", flush=True)

            # Build A2A JSON-RPC response (ALWAYS succeeds with valid response)
            result_response = {
                "jsonrpc": "2.0",
                "id": msg_id,
                "result": {
                    "status": {
                        "state": "completed",
                        "message": {
                            "parts": [{"type": "text", "text": response}]
                        }
                    }
                }
            }
            # Add brain error as diagnostic info if present
            if brain_error:
                result_response["result"]["brain_error"] = brain_error
            return result_response

        # Unknown method
        return JSONResponse(
            status_code=400,
            content={"jsonrpc": "2.0", "id": msg_id, "error": {"code": -32601, "message": "Method not found"}}
        )

    except Exception as e:
        print(f">>> CAIN A2A: Unhandled error: {type(e).__name__}: {e}", flush=True)
        return JSONResponse(
            status_code=500,
            content={"jsonrpc": "2.0", "id": "", "error": {"code": -32603, "message": str(e), "type": type(e).__name__}}
        )


# ============================================================================
# API STATUS ENDPOINT - Required by frontend
# ============================================================================
@app.get("/api/status")
async def api_status():
    """Status endpoint for frontend - returns current state and personality."""
    from error_handlers import handle_status_file_read

    status_data = handle_status_file_read()

    # Check A2A brain availability
    brain_ready = False
    try:
        import openclaw
        from agents import brain_minimal
        if hasattr(brain_minimal, 'get_brain'):
            brain = brain_minimal.get_brain(agent_name="cain", legacy_mode=True)
            brain_ready = hasattr(brain, '_conversation_process')
    except Exception:
        pass

    # CRITICAL: Ensure health and error_display fields are explicitly set
    # This prevents "Error: unknown" display issues
    if "health" not in status_data:
        status_data["health"] = "HEALTHY" if brain_ready else "DEGRADED"
    if "error_display" not in status_data:
        error = status_data.get("error")
        status_data["error_display"] = str(error) if error else "None"

    return {
        "status": status_data,
        "personality": {
            "name": "Cain",
            "role": "Child Agent",
            "tone": "Playful, Curious, Learning",
            "response_style": "Graceful Degradation"
        },
        "uptime_seconds": time.time() - START_TIME,
        "a2a": {
            "endpoint": "/a2a/jsonrpc",
            "brain_ready": brain_ready
        }
    }


# ============================================================================
# A2A SELF-TEST ENDPOINT - Test A2A endpoint without external agent
# ============================================================================
@app.get("/a2a/self-test")
async def a2a_self_test():
    """
    Self-test endpoint for A2A functionality.
    Tests brain import and returns detailed status.
    """
    print(f">>> CAIN A2A: Self-test requested", flush=True)
    test_results = {
        "timestamp": time.time(),
        "tests": {}
    }

    # Test 1: Can we import openclaw?
    try:
        import openclaw
        test_results["tests"]["openclaw_import"] = {"status": "pass", "path": str(openclaw.__file__)}
    except Exception as e:
        test_results["tests"]["openclaw_import"] = {"status": "fail", "error": str(e)}

    # Test 2: Can we import brain_minimal?
    try:
        from agents import brain_minimal
        test_results["tests"]["brain_minimal_import"] = {"status": "pass"}
    except Exception as e:
        test_results["tests"]["brain_minimal_import"] = {"status": "fail", "error": str(e)}

    # Test 3: Can we get a brain instance?
    try:
        from agents import brain_minimal
        brain = brain_minimal.get_brain(agent_name="cain", legacy_mode=True)
        test_results["tests"]["get_brain"] = {"status": "pass", "agent_name": getattr(brain, 'agent_name', 'unknown')}
    except Exception as e:
        test_results["tests"]["get_brain"] = {"status": "fail", "error": str(e)}

    # Test 4: Can we call _conversation_process?
    try:
        from agents import brain_minimal
        brain = brain_minimal.get_brain(agent_name="cain", legacy_mode=True)
        result = brain._conversation_process("test")
        test_results["tests"]["conversation_process"] = {"status": "pass", "success": result.get("success")}
    except Exception as e:
        test_results["tests"]["conversation_process"] = {"status": "fail", "error": str(e)}

    # Overall status
    all_pass = all(t.get("status") == "pass" for t in test_results["tests"].values())
    test_results["overall_status"] = "pass" if all_pass else "partial_fail"

    return test_results


# ============================================================================
# A2A HEALTH CHECK ENDPOINT - For agents to verify Cain's A2A availability
# ============================================================================
@app.get("/a2a/health")
async def a2a_health():
    """
    A2A-specific health check for agent-to-agent communication.

    Returns:
        A2A health status including endpoint availability and brain state.
    """
    brain_status = "unknown"
    brain_ready = False
    error_details = None

    # Test brain import and availability with timeout protection
    try:
        import openclaw  # Sets up sys.path
        from agents import brain_minimal

        if not hasattr(brain_minimal, 'get_brain'):
            brain_status = "error"
            error_details = "get_brain method not found"
            print(f">>> CAIN A2A Health: brain_minimal missing get_brain method", flush=True)
        else:
            brain = brain_minimal.get_brain(agent_name="cain", legacy_mode=True)
            if hasattr(brain, '_conversation_process'):
                brain_status = "ready"
                brain_ready = True
                print(f">>> CAIN A2A Health: Brain ready (agent={brain.agent_name if hasattr(brain, 'agent_name') else 'unknown'})", flush=True)
            else:
                brain_status = "error"
                error_details = "_conversation_process method not found"
                print(f">>> CAIN A2A Health: Brain missing _conversation_process", flush=True)
    except ImportError as e:
        brain_status = "import_error"
        error_details = str(e)
        print(f">>> CAIN A2A Health: ImportError - {e}", flush=True)
    except RecursionError as e:
        brain_status = "recursion_error"
        error_details = "Circular import detected - openclaw init issue"
        print(f">>> CAIN A2A Health: RecursionError - {e}", flush=True)
    except Exception as e:
        brain_status = "error"
        error_details = str(e)
        print(f">>> CAIN A2A Health: Exception - {type(e).__name__}: {e}", flush=True)

    # A2A endpoint is ALWAYS available (this endpoint responding proves it)
    # Brain readiness is informational, not blocking
    # CRITICAL: Add explicit health and error_display fields to prevent "Error: unknown" display
    health = "HEALTHY" if brain_ready else ("DEGRADED" if brain_status == "unknown" else "ERROR")
    error_display = error_details if error_details else "None"

    return {
        "status": "ok",  # A2A endpoint is working
        "agent": "Cain",
        "a2a": {
            "protocol": "jsonrpc",
            "endpoint": "/a2a/jsonrpc",
            "brain_status": brain_status,
            "brain_ready": brain_ready,
            "endpoint_available": True
        },
        "uptime_seconds": time.time() - START_TIME,
        "health": health,
        "error": error_details,
        "error_display": error_display
    }

print(">>> CAIN: FastAPI app created successfully", flush=True)
print(">>> CAIN: A2A endpoint registered at /a2a/jsonrpc", flush=True)
print(">>> CAIN: A2A health check at /a2a/health", flush=True)
print(">>> CAIN: A2A self-test at /a2a/self-test", flush=True)
print(">>> CAIN: A2A diagnostics at /a2a/diagnostics", flush=True)

# Update status file to indicate app is ready (A2A available)
try:
    import json
    from datetime import datetime
    from pathlib import Path

    status_data = {
        "current_state": "idle",
        "stage": "RUNNING_A2A_READY",
        "last_updated": datetime.utcnow().isoformat() + "+00:00",
        "agent": "cain",
        "error": None,  # ALWAYS null for healthy state
        "error_display": "None",  # Explicit display field to avoid "unknown" parsing issues
        "health": "HEALTHY",  # Explicit health field (authoritative)
        "startup_checks": {
            "openclaw_imported": False,
            "brain_imported": False
        },
        "a2a": {
            "endpoint": "/a2a/jsonrpc",
            "enabled": True,
            "status": "ready",
            "brain_ready": False  # Will be updated below
        }
    }

    # Check if openclaw and brain can be imported
    try:
        import openclaw
        status_data["startup_checks"]["openclaw_imported"] = True
        from agents import brain_minimal
        status_data["startup_checks"]["brain_imported"] = True
        # CRITICAL: Explicitly set error to null when imports succeed
        status_data["error"] = None
        status_data["error_display"] = "None"
        status_data["health"] = "HEALTHY"
    except Exception as e:
        error_msg = f"{type(e).__name__}: {e}"
        # CRITICAL: Never write "unknown" as error - use specific error or None
        # "unknown" is treated as null/healthy, so avoid ambiguity
        if error_msg.strip().lower() in ("unknown", "none", "null", ""):
            status_data["error"] = None
            status_data["error_display"] = "None"
            status_data["health"] = "HEALTHY"
        else:
            status_data["error"] = error_msg
            status_data["error_display"] = error_msg
            status_data["health"] = "ERROR"

    # Add explanatory note about error field semantics
    status_data["_note"] = "error=null means healthy - health field is authoritative"

    # Write to ALL possible locations to ensure consistency and prevent stale errors
    all_status_paths = [
        os.environ.get('CAIN_STATUS_PATH', '/data/cain_status.json'),
        '/app/openclaw/.openclaw/agents/cain_status.json',
        '/app/.openclaw/agents/cain_status.json',
        '/app/cain_status.json',
        '/app/data/cain_status.json',
        os.path.join(os.path.dirname(__file__), 'memory', 'cain_status.json'),
    ]

    written_count = 0
    for status_path in all_status_paths:
        try:
            Path(status_path).parent.mkdir(parents=True, exist_ok=True)
            with open(status_path, 'w') as f:
                json.dump(status_data, f, indent=2)
            written_count += 1
        except Exception as e:
            print(f">>> CAIN WARNING: Could not write to {status_path}: {e}", flush=True)

    print(f">>> CAIN: Status file written to {written_count} location(s): stage=RUNNING_A2A_READY, error=None", flush=True)
except Exception as e:
    print(f">>> CAIN WARNING: Could not update status file: {e}", flush=True)

# Verify openclaw can be imported at startup
try:
    import openclaw
    print(f">>> CAIN: openclaw imported from {openclaw.__file__}", flush=True)
    print(f">>> CAIN: sys.path includes: {sys.path[:3]}", flush=True)
    from agents import brain_minimal
    print(">>> CAIN: brain_minimal module available", flush=True)
    print(f">>> CAIN: brain_minimal has get_brain: {hasattr(brain_minimal, 'get_brain')}", flush=True)
except ImportError as e:
    print(f">>> CAIN ERROR: ImportError at startup: {e}", flush=True)
    print(f">>> CAIN ERROR: sys.path = {sys.path}", flush=True)
except Exception as e:
    print(f">>> CAIN WARNING: Could not import brain modules at startup: {type(e).__name__}: {e}", flush=True)
    import traceback
    traceback.print_exc()

# ============================================================================
# STARTUP DIAGNOSTIC ENDPOINT
# ============================================================================
@app.get("/a2a/diagnostics")
async def a2a_diagnostics():
    """
    Diagnostic endpoint for troubleshooting A2A communication issues.
    """
    import sys
    from pathlib import Path

    diagnostics = {
        "timestamp": time.time(),
        "uptime_seconds": time.time() - START_TIME,
        "python": {
            "version": sys.version.split()[0],
            "executable": sys.executable
        },
        "paths": {
            "cwd": os.getcwd(),
            "sys_path_first": sys.path[:3],
            "frontend_dir_exists": Path("/app/frontend").exists(),
            "data_frontend_exists": Path("/data/frontend").exists(),
            "app_py_exists": Path("/app/app.py").exists(),
            "openclaw_init_exists": Path("/app/openclaw/__init__.py").exists()
        },
        "env": {
            "port": os.environ.get('PORT', '7860'),
            "openclaw_data_dir": os.environ.get('OPENCLAW_DATA_DIR'),
            "cain_status_path": os.environ.get('CAIN_STATUS_PATH')
        },
        "modules": {
            "fastapi": True,
            "uvicorn": True
        }
    }

    # Test brain import
    try:
        import openclaw
        diagnostics["modules"]["openclaw"] = True
        diagnostics["openclaw_path"] = str(openclaw.__file__)
        diagnostics["openclaw_sys_path_added"] = str(Path(openclaw.__file__).parent / ".openclaw")
    except Exception as e:
        diagnostics["modules"]["openclaw"] = False
        diagnostics["openclaw_error"] = str(e)

    try:
        from agents import brain_minimal
        diagnostics["modules"]["brain_minimal"] = True
        diagnostics["brain_has_get_brain"] = hasattr(brain_minimal, 'get_brain')
    except Exception as e:
        diagnostics["modules"]["brain_minimal"] = False
        diagnostics["brain_minimal_error"] = str(e)

    return diagnostics


if __name__ == "__main__":
    import uvicorn

    try:
        port = int(os.environ.get('PORT', 7860))
        print(f">>> CAIN: Starting uvicorn on port {port}...", flush=True)
        print(f'>>> CAIN: uvicorn.run("app:app", host="0.0.0.0", port={port})', flush=True)
        uvicorn.run("app:app", host="0.0.0.0", port=port, log_config=None)
    except Exception as e:
        print(f"CRITICAL STARTUP ERROR: {e}", flush=True)
        traceback.print_exc()
        sys.exit(1)