"""
History Router - Upload history management

Note: This is a simplified version. The original Next.js version
stores history in memory/file. For FastAPI, we'll use a simple
JSON file approach similar to prompts.
"""
from fastapi import APIRouter, HTTPException, UploadFile, File, Form
from models.responses import HistoryResponse, HistoryItem, ErrorResponse
from services.whisk_client import WhiskClient
from pathlib import Path
import json
import uuid
import base64
from typing import Optional
from datetime import datetime

router = APIRouter(prefix="/history", tags=["History"])

# History storage
HISTORY_FILE = Path(__file__).parent.parent.parent / "data" / "history.json"


def load_history() -> list:
    """Load history from JSON file"""
    try:
        if HISTORY_FILE.exists():
            return json.loads(HISTORY_FILE.read_text())
    except:
        pass
    return []


def save_history(history: list) -> None:
    """Save history to JSON file"""
    HISTORY_FILE.parent.mkdir(parents=True, exist_ok=True)
    HISTORY_FILE.write_text(json.dumps(history, indent=2))


@router.get(
    "",
    response_model=HistoryResponse,
    responses={500: {"model": ErrorResponse}}
)
async def get_history(category: Optional[str] = None):
    """
    Get upload history.
    
    - **category**: Optional filter by category (subject, scene, style)
    """
    try:
        history = load_history()

        if category:
            history = [h for h in history if h.get("category") == category]

        return HistoryResponse(history=[HistoryItem(**h) for h in history])

    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))


@router.post(
    "",
    response_model=HistoryItem,
    responses={
        400: {"model": ErrorResponse},
        500: {"model": ErrorResponse}
    }
)
async def upload_to_history(
    file: UploadFile = File(...),
    category: str = Form(default="subject"),
    cookies: Optional[str] = Form(default=None)
):
    """
    Upload an image to history.
    
    - **file**: Image file to upload
    - **category**: Category (subject, scene, style)
    - **cookies**: Optional Whisk cookies to also upload to Whisk
    """
    try:
        # Read file
        content = await file.read()
        base64_data = base64.b64encode(content).decode('utf-8')
        mime_type = file.content_type or 'image/png'

        # Upload to Whisk if cookies provided
        media_id = None
        if cookies:
            try:
                client = WhiskClient(cookies)
                media_id = await client.upload_reference_image(base64_data, mime_type, category)
            except Exception as e:
                print(f"[History] Whisk upload failed: {e}")

        # Create history item
        new_item = {
            "id": str(uuid.uuid4()),
            "url": f"data:{mime_type};base64,{base64_data}",
            "originalName": file.filename or "upload.png",
            "category": category,
            "mediaId": media_id,
            "createdAt": int(datetime.now().timestamp() * 1000)
        }

        # Save to history
        history = load_history()
        history.insert(0, new_item)  # Add to beginning
        save_history(history)

        return HistoryItem(**new_item)

    except Exception as e:
        print(f"Upload error: {e}")
        raise HTTPException(status_code=500, detail=str(e))


@router.delete(
    "/{item_id}",
    responses={
        404: {"model": ErrorResponse},
        500: {"model": ErrorResponse}
    }
)
async def delete_history_item(item_id: str):
    """
    Delete an item from history.
    
    - **item_id**: ID of the history item to delete
    """
    try:
        history = load_history()
        original_len = len(history)

        history = [h for h in history if h.get("id") != item_id]

        if len(history) == original_len:
            raise HTTPException(status_code=404, detail="Item not found")

        save_history(history)

        return {"success": True, "deleted": item_id}

    except HTTPException:
        raise
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))


@router.delete(
    "",
    responses={500: {"model": ErrorResponse}}
)
async def clear_history():
    """
    Clear all history items.
    """
    try:
        save_history([])
        return {"success": True, "message": "History cleared"}
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))