"""
CivicAI FastAPI Server — OpenEnv Compliant API

Endpoints:
  POST /reset     — Reset environment with task_id
  POST /step      — Execute action
  GET  /state     — Get current state
  GET  /tasks     — List available tasks
  GET  /metrics   — Get evaluation metrics
  GET  /health    — Health check
  GET  /          — Dashboard UI
"""

from __future__ import annotations

import os
from contextlib import asynccontextmanager
from pathlib import Path
from typing import Any

from fastapi import FastAPI, HTTPException
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import FileResponse, JSONResponse
from fastapi.staticfiles import StaticFiles
from pydantic import BaseModel

from civicai.environment import CivicAIEnv
from civicai.models import Action, Observation
from civicai.tasks import TASKS
from agents.orchestrator import Orchestrator


# ---------------------------------------------------------------------------
# App Setup
# ---------------------------------------------------------------------------

# Global environment and orchestrator (initialized before lifespan)
env = CivicAIEnv()
orchestrator = Orchestrator(env)
step_history: list[dict[str, Any]] = []


@asynccontextmanager
async def lifespan(app: FastAPI):
    """Auto-reset the environment on server startup so Step/Auto work immediately."""
    try:
        orchestrator.reset("stabilize_economy")
        print("[CivicAI] Environment auto-initialized with task: stabilize_economy")
    except Exception as exc:
        print(f"[CivicAI] WARNING: Could not auto-initialize environment: {exc}")
    yield  # Server runs here


app = FastAPI(
    title="CivicAI Society Simulator",
    description="Multi-agent society decision-making environment (OpenEnv compliant)",
    version="1.0.0",
    lifespan=lifespan,
)

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)


# ---------------------------------------------------------------------------
# Request / Response Models
# ---------------------------------------------------------------------------

class ResetRequest(BaseModel):
    task_id: str = "stabilize_economy"
    max_steps: int | None = None


class StartSimulationRequest(BaseModel):
    task_id: str = "stabilize_economy"
    max_steps: int = 50


class StepRequest(BaseModel):
    action: Action | None = None  # None = use multi-agent system
    use_agents: bool = True


class StepResponse(BaseModel):
    observation: dict[str, Any]
    reward: float
    done: bool
    info: dict[str, Any]


# ---------------------------------------------------------------------------
# OpenEnv Endpoints
# ---------------------------------------------------------------------------

@app.post("/reset")
async def reset(req: ResetRequest) -> dict[str, Any]:
    """Reset the environment with a specific task."""
    global step_history
    step_history = []
    try:
        obs = orchestrator.reset(req.task_id, req.max_steps)
        step_history.append({"turn": 0, "observation": obs.model_dump()})
        return {
            "observation": obs.model_dump(),
            "task": TASKS[req.task_id].__dict__
            if req.task_id in TASKS else {},
        }
    except ValueError as e:
        raise HTTPException(status_code=400, detail=str(e))


@app.post("/step")
async def step(req: StepRequest) -> StepResponse:
    """Execute one step in the environment."""
    try:
        # Auto-initialize if env was never reset (e.g. first page load)
        if env._state is None:
            orchestrator.reset("stabilize_economy")

        if req.use_agents or req.action is None:
            obs, reward, done, info = orchestrator.run_step()
        else:
            obs, reward, done, info = env.step(req.action)

        # Sanitize info for JSON (remove non-serializable)
        safe_info = _sanitize_info(info)

        step_history.append({
            "turn": obs.turn,
            "observation": obs.model_dump(),
            "reward": reward,
            "done": done,
        })

        return StepResponse(
            observation=obs.model_dump(),
            reward=reward,
            done=done,
            info=safe_info,
        )
    except RuntimeError as e:
        raise HTTPException(status_code=500, detail=str(e))


@app.get("/state")
async def get_state() -> dict[str, Any]:
    """Get full internal state."""
    return env.state().model_dump()


@app.get("/tasks")
async def list_tasks() -> dict[str, Any]:
    """List available tasks."""
    return {
        tid: {
            "name": t.name,
            "difficulty": t.difficulty,
            "description": t.description,
            "max_steps": t.max_steps,
        }
        for tid, t in TASKS.items()
    }


@app.get("/metrics")
async def get_metrics() -> dict[str, Any]:
    """Get current metrics and history."""
    return {
        "step_history": step_history[-100:],  # Last 100 steps
        "total_steps": len(step_history),
        "emergent_summary": env.tracker.get_summary() if env.tracker else {},
        "debate_history": [
            d.model_dump() for d in orchestrator.debate_history[-10:]
        ],
    }


@app.post("/start-simulation")
async def start_simulation(req: StartSimulationRequest) -> dict[str, Any]:
    """Run a complete episode and return the full trajectory."""
    global step_history
    step_history = []
    result = orchestrator.run_episode(req.task_id, req.max_steps)
    
    # Sanitize info dictionary for JSON serialization
    for step in result.get("step_log", []):
        if "info" in step:
            step["info"] = _sanitize_info(step["info"])
            
    return result


@app.get("/health")
async def health_check() -> dict[str, str]:
    """Health check endpoint."""
    return {"status": "healthy", "version": "1.0.0"}


@app.get("/run-episode")
async def run_episode(task_id: str = "stabilize_economy", max_steps: int | None = None) -> dict[str, Any]:
    """Run a complete episode and return results."""
    global step_history
    step_history = []
    result = orchestrator.run_episode(task_id, max_steps)
    return result


# ---------------------------------------------------------------------------
# Dashboard Static Files
# ---------------------------------------------------------------------------

DASHBOARD_DIR = Path(__file__).parent.parent / "dashboard"

if DASHBOARD_DIR.exists():
    @app.get("/")
    async def serve_dashboard():
        return FileResponse(DASHBOARD_DIR / "index.html")

    app.mount(
        "/dashboard",
        StaticFiles(directory=str(DASHBOARD_DIR)),
        name="dashboard",
    )


# ---------------------------------------------------------------------------
# Helpers
# ---------------------------------------------------------------------------

def _sanitize_info(info: dict[str, Any]) -> dict[str, Any]:
    """Make info dict JSON serializable."""
    clean: dict[str, Any] = {}
    for k, v in info.items():
        if isinstance(v, dict):
            clean[k] = _sanitize_info(v)
        elif isinstance(v, (str, int, float, bool, type(None))):
            clean[k] = v
        elif isinstance(v, list):
            clean[k] = v
        else:
            clean[k] = str(v)
    return clean


# ---------------------------------------------------------------------------
# Entry Point
# ---------------------------------------------------------------------------

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