from fastapi import APIRouter, HTTPException, Query
from pydantic import BaseModel, Field, validator
from typing import List, Optional

from .utils import (
    save_cameras,
    load_cameras,
    user_exists,
    _bucket_key,
    _list_prefix,
    _read_bucket_json,
    _write_bucket_json,
    BUCKET_ID,
)

from huggingface_hub import batch_bucket_files, download_bucket_files
import tempfile
import os

print(" CAMERA API LOADED ")

router = APIRouter(prefix="/camera", tags=["Camera"])


# ================= MODELS =================

class CameraData(BaseModel):
    user_id: str = Field(..., min_length=1)
    camera_name: str = Field(..., min_length=1)
    camera_loc: Optional[List[float]] = None

    @validator("camera_loc")
    def validate_loc(cls, loc):
        if loc is None:
            return loc
        if len(loc) != 2:
            raise ValueError("camera_loc must be [lat, lon]")
        lat, lon = loc
        if not (-90 <= lat <= 90):
            raise ValueError("Latitude must be between -90 and 90")
        if not (-180 <= lon <= 180):
            raise ValueError("Longitude must be between -180 and 180")
        return loc


class EditCameraData(BaseModel):
    user_id: str
    old_camera_name: str
    new_camera_name: str
    new_camera_loc: Optional[List[float]] = None   # ← optional, won't error if missing

    @validator("new_camera_loc")
    def validate_loc(cls, loc):
        if loc is None:
            return loc
        if len(loc) != 2:
            raise ValueError("new_camera_loc must be [lat, lon]")
        lat, lon = loc
        if not (-90 <= lat <= 90):
            raise ValueError("Latitude must be between -90 and 90")
        if not (-180 <= lon <= 180):
            raise ValueError("Longitude must be between -180 and 180")
        return loc


# ================= ROUTES =================

@router.get("/")
def home():
    return {
        "message": "Camera API is Running",
        "endpoints": [
            "/camera/add_camera",
            "/camera/edit_camera",
            "/camera/delete_camera",
            "/camera/get_cameras?user_id=<id>"
        ]
    }


# ---------- GET CAMERAS ----------
@router.get("/get_cameras")
def get_cameras(user_id: str = Query(...)):
    if not user_exists(user_id):
        raise HTTPException(status_code=404, detail="User not found")
    cameras = load_cameras(user_id)
    return {"success": True, "user_id": user_id, "cameras": cameras, "count": len(cameras)}


# ---------- ADD CAMERA ----------
@router.post("/add_camera")
def add_camera(data: CameraData):
    cameras = load_cameras(data.user_id)
    if len(cameras) >= 2:
        raise HTTPException(status_code=400, detail="Only 2 cameras allowed")
    for cam in cameras:
        if cam["camera_name"].lower() == data.camera_name.lower():
            raise HTTPException(status_code=400, detail="Camera already exists")
    cameras.append({"camera_name": data.camera_name, "camera_loc": data.camera_loc})
    save_cameras(data.user_id, cameras)
    return {"success": True, "camera": data.camera_name}


# ---------- EDIT CAMERA ----------
@router.put("/edit_camera")
def edit_camera(data: EditCameraData):
    if not user_exists(data.user_id):
        raise HTTPException(status_code=404, detail="User not found")

    cameras = load_cameras(data.user_id)

    # Only block duplicate name if name is actually changing
    name_changing = data.new_camera_name.lower() != data.old_camera_name.lower()
    if name_changing:
        if any(cam["camera_name"].lower() == data.new_camera_name.lower() for cam in cameras):
            raise HTTPException(
                status_code=400,
                detail=f"Camera name '{data.new_camera_name}' already exists"
            )

    camera_found = False
    for cam in cameras:
        if cam["camera_name"].lower() == data.old_camera_name.lower():
            old_name = cam["camera_name"]

            # Apply updates
            cam["camera_name"] = data.new_camera_name
            if data.new_camera_loc is not None:       # only update if provided
                cam["camera_loc"] = data.new_camera_loc

            camera_found = True

            # ── Rename bucket files only if name changed ──────────
            if name_changing:
                old_prefix = _bucket_key(data.user_id, old_name)
                new_prefix = _bucket_key(data.user_id, data.new_camera_name)

                old_files = _list_prefix(old_prefix)

                for item in old_files:
                    old_key = item.path
                    new_key = old_key.replace(old_prefix, new_prefix, 1)

                    # Rename detection JSON filename inside the key
                    if f"{old_name}_detections.json" in new_key:
                        new_key = new_key.replace(
                            f"{old_name}_detections.json",
                            f"{data.new_camera_name}_detections.json"
                        )

                    try:
                        if old_key.endswith(".json"):
                            # JSON: read and re-write
                            content = _read_bucket_json(old_key)
                            if content is not None:
                                _write_bucket_json(new_key, content)
                        else:
                            # Binary (images): download → re-upload
                            with tempfile.NamedTemporaryFile(delete=False) as tf:
                                tmp_path = tf.name
                            download_bucket_files(
                                BUCKET_ID,
                                files=[(old_key, tmp_path)],
                                
                            )
                            with open(tmp_path, "rb") as f:
                                raw = f.read()
                            os.unlink(tmp_path)
                            batch_bucket_files(
                                BUCKET_ID,
                                add=[(raw, new_key)],
                                
                            )

                        # Delete old key after successful copy
                        batch_bucket_files(
                            BUCKET_ID,
                            delete=[old_key],
                            
                        )

                    except Exception as e:
                        raise HTTPException(
                            status_code=500,
                            detail=f"Failed to move bucket file '{old_key}': {str(e)}"
                        )

            save_cameras(data.user_id, cameras)
            return {"success": True, "updated": cam}

    if not camera_found:
        raise HTTPException(status_code=404, detail="Camera not found")


# ---------- DELETE CAMERA ----------
@router.delete("/delete_camera")
def delete_camera(user_id: str = Query(...), camera_name: str = Query(...)):
    if not user_exists(user_id):
        raise HTTPException(status_code=404, detail="User not found")

    cameras = load_cameras(user_id)
    new_list = [c for c in cameras if c["camera_name"].lower() != camera_name.lower()]
    if len(new_list) == len(cameras):
        raise HTTPException(status_code=404, detail="Camera not found")

    # Delete all bucket files under this camera prefix
    cam_prefix = _bucket_key(user_id, camera_name)
    cam_files  = _list_prefix(cam_prefix)

    if cam_files:
        keys_to_delete = [item.path for item in cam_files]
        try:
            batch_bucket_files(
                BUCKET_ID,
                delete=keys_to_delete,
                
            )
        except Exception as e:
            raise HTTPException(
                status_code=500,
                detail=f"Failed to delete camera files from bucket: {str(e)}"
            )

    save_cameras(user_id, new_list)
    return {"success": True, "deleted": camera_name}