"""
SAAP Agent Manager - FastAPI Backend
Modular agent management with JSON Schema validation
"""

from fastapi import FastAPI, HTTPException, WebSocket, WebSocketDisconnect
from fastapi.middleware.cors import CORSMiddleware
from pydantic import BaseModel, Field
from typing import Dict, List, Optional, Any
from datetime import datetime, timezone
import json
import asyncio
import logging
from pathlib import Path

# Import agent templates and schema
import sys
sys.path.append(str(Path(__file__).parent.parent))

app = FastAPI(
    title="SAAP Agent Manager API",
    description="Modular Multi-Agent Management System",
    version="1.0.0"
)

# CORS middleware for Vue.js frontend
app.add_middleware(
    CORSMiddleware,
    allow_origins=["http://localhost:5173", "http://localhost:3000"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# Logging setup
logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)

# Pydantic Models based on JSON Schema
class AgentModel(BaseModel):
    provider: str = Field(..., description="Model provider")
    name: str = Field(..., description="Model name")
    endpoint: Optional[str] = Field(None, description="API endpoint")
    api_key: Optional[str] = Field(None, description="API key")

class AgentPersonality(BaseModel):
    system_prompt: str = Field(..., description="System prompt")
    temperature: float = Field(0.7, ge=0.0, le=2.0)
    max_tokens: int = Field(1000, ge=1, le=4096)

class AgentMetrics(BaseModel):
    messages_processed: int = Field(0, ge=0)
    average_response_time: float = Field(0.0, ge=0.0)
    uptime: str = Field("0m")
    error_count: int = Field(0, ge=0)

class Agent(BaseModel):
    id: str = Field(..., regex="^[a-z_]+$")
    name: str
    type: str = Field(..., regex="^(coordinator|specialist|developer|analyst|utility)$")
    color: str = Field(..., regex="^#[0-9A-Fa-f]{6}$")
    avatar: Optional[str] = None
    status: str = Field("inactive", regex="^(inactive|starting|active|stopping|error)$")
    capabilities: List[str] = Field(default_factory=list)
    model: AgentModel
    personality: AgentPersonality
    metrics: AgentMetrics = Field(default_factory=AgentMetrics)
    created_at: datetime = Field(default_factory=lambda: datetime.now(timezone.utc))
    updated_at: datetime = Field(default_factory=lambda: datetime.now(timezone.utc))

class MessageRequest(BaseModel):
    sender_id: str
    receiver_id: str
    content: str
    message_type: str = "request"
    metadata: Dict[str, Any] = Field(default_factory=dict)

class MessageResponse(BaseModel):
    id: str
    sender_id: str
    receiver_id: str
    content: str
    response: Optional[str] = None
    timestamp: datetime
    status: str = "sent"

# Global agent storage (in production, use database)
agents: Dict[str, Agent] = {}
messages: List[MessageResponse] = []
websocket_connections: List[WebSocket] = []

# Load agent templates
def load_agent_templates():
    """Load agent templates from JSON file"""
    try:
        template_path = Path(__file__).parent.parent / "models" / "agent_templates.json"
        with open(template_path, 'r', encoding='utf-8') as f:
            data = json.load(f)
            return data["templates"]
    except Exception as e:
        logger.error(f"Failed to load agent templates: {e}")
        return {}

agent_templates = load_agent_templates()

# WebSocket connection manager
class ConnectionManager:
    def __init__(self):
        self.active_connections: List[WebSocket] = []

    async def connect(self, websocket: WebSocket):
        await websocket.accept()
        self.active_connections.append(websocket)
        logger.info(f"WebSocket connected. Total connections: {len(self.active_connections)}")

    def disconnect(self, websocket: WebSocket):
        if websocket in self.active_connections:
            self.active_connections.remove(websocket)
        logger.info(f"WebSocket disconnected. Total connections: {len(self.active_connections)}")

    async def broadcast(self, data: dict):
        """Broadcast data to all connected clients"""
        for connection in self.active_connections:
            try:
                await connection.send_json(data)
            except Exception as e:
                logger.error(f"Error broadcasting to WebSocket: {e}")

manager = ConnectionManager()

# Agent Management Endpoints
@app.get("/api/v1/agents", response_model=List[Agent])
async def list_agents():
    """Get all registered agents"""
    return list(agents.values())

@app.get("/api/v1/agents/templates")
async def get_agent_templates():
    """Get available agent templates"""
    return agent_templates

@app.post("/api/v1/agents", response_model=Agent)
async def create_agent(agent_data: dict):
    """Create a new agent from template or custom data"""
    try:
        # If template_id provided, use template as base
        if "template_id" in agent_data and agent_data["template_id"] in agent_templates:
            template = agent_templates[agent_data["template_id"]].copy()
            template.update(agent_data)
            agent_data = template
        
        # Add default metrics and timestamps
        agent_data.setdefault("metrics", {
            "messages_processed": 0,
            "average_response_time": 0.0,
            "uptime": "0m",
            "error_count": 0
        })
        
        agent = Agent(**agent_data)
        agents[agent.id] = agent
        
        # Broadcast to WebSocket clients
        await manager.broadcast({
            "type": "agent_created",
            "agent": agent.dict()
        })
        
        logger.info(f"Agent created: {agent.id}")
        return agent
        
    except Exception as e:
        logger.error(f"Error creating agent: {e}")
        raise HTTPException(status_code=400, detail=str(e))

@app.get("/api/v1/agents/{agent_id}", response_model=Agent)
async def get_agent(agent_id: str):
    """Get specific agent by ID"""
    if agent_id not in agents:
        raise HTTPException(status_code=404, detail="Agent not found")
    return agents[agent_id]

@app.put("/api/v1/agents/{agent_id}", response_model=Agent)
async def update_agent(agent_id: str, agent_data: dict):
    """Update existing agent"""
    if agent_id not in agents:
        raise HTTPException(status_code=404, detail="Agent not found")
    
    try:
        # Preserve existing data and update with new data
        existing_agent = agents[agent_id].dict()
        existing_agent.update(agent_data)
        existing_agent["updated_at"] = datetime.now(timezone.utc)
        
        agent = Agent(**existing_agent)
        agents[agent_id] = agent
        
        # Broadcast update
        await manager.broadcast({
            "type": "agent_updated", 
            "agent": agent.dict()
        })
        
        logger.info(f"Agent updated: {agent_id}")
        return agent
        
    except Exception as e:
        logger.error(f"Error updating agent: {e}")
        raise HTTPException(status_code=400, detail=str(e))

@app.delete("/api/v1/agents/{agent_id}")
async def delete_agent(agent_id: str):
    """Delete agent"""
    if agent_id not in agents:
        raise HTTPException(status_code=404, detail="Agent not found")
    
    del agents[agent_id]
    
    # Broadcast deletion
    await manager.broadcast({
        "type": "agent_deleted",
        "agent_id": agent_id
    })
    
    logger.info(f"Agent deleted: {agent_id}")
    return {"message": "Agent deleted successfully"}

# Agent Control Endpoints
@app.post("/api/v1/agents/{agent_id}/start")
async def start_agent(agent_id: str):
    """Start an agent"""
    if agent_id not in agents:
        raise HTTPException(status_code=404, detail="Agent not found")
    
    agent = agents[agent_id]
    
    # Simulate agent startup process
    agent.status = "starting"
    agent.updated_at = datetime.now(timezone.utc)
    
    # Broadcast status change
    await manager.broadcast({
        "type": "agent_status_changed",
        "agent_id": agent_id,
        "status": "starting"
    })
    
    # Simulate startup delay
    await asyncio.sleep(2)
    
    # Mark as active
    agent.status = "active"
    agent.metrics.uptime = "0m"
    
    await manager.broadcast({
        "type": "agent_status_changed", 
        "agent_id": agent_id,
        "status": "active"
    })
    
    logger.info(f"Agent started: {agent_id}")
    return {"message": f"Agent {agent_id} started successfully"}

@app.post("/api/v1/agents/{agent_id}/stop")
async def stop_agent(agent_id: str):
    """Stop an agent"""
    if agent_id not in agents:
        raise HTTPException(status_code=404, detail="Agent not found")
    
    agent = agents[agent_id]
    agent.status = "stopping"
    agent.updated_at = datetime.now(timezone.utc)
    
    # Broadcast status change
    await manager.broadcast({
        "type": "agent_status_changed",
        "agent_id": agent_id, 
        "status": "stopping"
    })
    
    # Simulate shutdown delay
    await asyncio.sleep(1)
    
    agent.status = "inactive"
    
    await manager.broadcast({
        "type": "agent_status_changed",
        "agent_id": agent_id,
        "status": "inactive"
    })
    
    logger.info(f"Agent stopped: {agent_id}")
    return {"message": f"Agent {agent_id} stopped successfully"}

# Message Management
@app.post("/api/v1/messages/send", response_model=MessageResponse)
async def send_message(message_req: MessageRequest):
    """Send message between agents"""
    if message_req.sender_id not in agents:
        raise HTTPException(status_code=404, detail="Sender agent not found")
    if message_req.receiver_id not in agents:
        raise HTTPException(status_code=404, detail="Receiver agent not found")
    
    # Create message
    message = MessageResponse(
        id=f"msg_{len(messages)}_{datetime.now().timestamp()}",
        sender_id=message_req.sender_id,
        receiver_id=message_req.receiver_id,
        content=message_req.content,
        timestamp=datetime.now(timezone.utc),
        status="sent"
    )
    
    messages.append(message)
    
    # Update sender metrics
    agents[message_req.sender_id].metrics.messages_processed += 1
    
    # Broadcast message
    await manager.broadcast({
        "type": "message_sent",
        "message": message.dict()
    })
    
    # TODO: Implement actual AI response via colossus API
    # For now, simulate a response
    await asyncio.sleep(0.5)
    
    response_content = f"Response from {agents[message_req.receiver_id].name}: I received your message '{message_req.content}'"
    
    response_message = MessageResponse(
        id=f"msg_{len(messages)}_{datetime.now().timestamp()}",
        sender_id=message_req.receiver_id,
        receiver_id=message_req.sender_id,
        content=response_content,
        timestamp=datetime.now(timezone.utc),
        status="sent"
    )
    
    messages.append(response_message)
    
    # Update receiver metrics
    agents[message_req.receiver_id].metrics.messages_processed += 1
    
    await manager.broadcast({
        "type": "message_received",
        "message": response_message.dict()
    })
    
    logger.info(f"Message sent: {message_req.sender_id} -> {message_req.receiver_id}")
    return message

@app.get("/api/v1/messages", response_model=List[MessageResponse])
async def list_messages(limit: int = 100, agent_id: Optional[str] = None):
    """Get messages with optional filtering"""
    filtered_messages = messages
    
    if agent_id:
        filtered_messages = [
            msg for msg in messages 
            if msg.sender_id == agent_id or msg.receiver_id == agent_id
        ]
    
    return filtered_messages[-limit:]

# System Status
@app.get("/api/v1/system/status")
async def get_system_status():
    """Get overall system status"""
    active_agents = len([a for a in agents.values() if a.status == "active"])
    total_messages = len(messages)
    
    return {
        "status": "healthy",
        "agents": {
            "total": len(agents),
            "active": active_agents,
            "inactive": len(agents) - active_agents
        },
        "messages": {
            "total": total_messages
        },
        "websocket_connections": len(manager.active_connections),
        "timestamp": datetime.now(timezone.utc)
    }

# WebSocket endpoint for real-time updates
@app.websocket("/ws")
async def websocket_endpoint(websocket: WebSocket):
    await manager.connect(websocket)
    try:
        while True:
            # Keep connection alive
            await websocket.receive_text()
    except WebSocketDisconnect:
        manager.disconnect(websocket)

# Initialize with templates on startup
@app.on_event("startup")
async def startup_event():
    """Initialize agents from templates"""
    logger.info("SAAP Agent Manager starting up...")
    
    # Create default agents from templates
    for template_id, template_data in agent_templates.items():
        try:
            template_data["created_at"] = datetime.now(timezone.utc)
            template_data["updated_at"] = datetime.now(timezone.utc)
            agent = Agent(**template_data)
            agents[agent.id] = agent
            logger.info(f"Loaded agent template: {agent.id}")
        except Exception as e:
            logger.error(f"Error loading template {template_id}: {e}")
    
    logger.info(f"Agent Manager ready with {len(agents)} agents")

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=8000, reload=True)