from fastapi import APIRouter, UploadFile, File, BackgroundTasks
from fastapi import Depends, HTTPException, status
from starlette.responses import StreamingResponse

from pydantic import BaseModel

import requests
import os
import aiohttp
import json

from utils.misc import calculate_sha256

from config import OLLAMA_API_BASE_URL, DATA_DIR, UPLOAD_DIR
from constants import ERROR_MESSAGES


router = APIRouter()


class UploadBlobForm(BaseModel):
    filename: str


from urllib.parse import urlparse


def parse_huggingface_url(hf_url):
    try:
        # Parse the URL
        parsed_url = urlparse(hf_url)

        # Get the path and split it into components
        path_components = parsed_url.path.split("/")

        # Extract the desired output
        user_repo = "/".join(path_components[1:3])
        model_file = path_components[-1]

        return model_file
    except ValueError:
        return None


async def download_file_stream(url, file_path, file_name, chunk_size=1024 * 1024):
    done = False

    if os.path.exists(file_path):
        current_size = os.path.getsize(file_path)
    else:
        current_size = 0

    headers = {"Range": f"bytes={current_size}-"} if current_size > 0 else {}

    timeout = aiohttp.ClientTimeout(total=600)  # Set the timeout

    async with aiohttp.ClientSession(timeout=timeout) as session:
        async with session.get(url, headers=headers) as response:
            total_size = int(response.headers.get("content-length", 0)) + current_size

            with open(file_path, "ab+") as file:
                async for data in response.content.iter_chunked(chunk_size):
                    current_size += len(data)
                    file.write(data)

                    done = current_size == total_size
                    progress = round((current_size / total_size) * 100, 2)
                    yield f'data: {{"progress": {progress}, "completed": {current_size}, "total": {total_size}}}\n\n'

                if done:
                    file.seek(0)
                    hashed = calculate_sha256(file)
                    file.seek(0)

                    url = f"{OLLAMA_API_BASE_URL}/blobs/sha256:{hashed}"
                    response = requests.post(url, data=file)

                    if response.ok:
                        res = {
                            "done": done,
                            "blob": f"sha256:{hashed}",
                            "name": file_name,
                        }
                        os.remove(file_path)

                        yield f"data: {json.dumps(res)}\n\n"
                    else:
                        raise "Ollama: Could not create blob, Please try again."


@router.get("/download")
async def download(
    url: str,
):
    # url = "https://huggingface.co/TheBloke/stablelm-zephyr-3b-GGUF/resolve/main/stablelm-zephyr-3b.Q2_K.gguf"
    file_name = parse_huggingface_url(url)

    if file_name:
        file_path = f"{UPLOAD_DIR}/{file_name}"

        return StreamingResponse(
            download_file_stream(url, file_path, file_name),
            media_type="text/event-stream",
        )
    else:
        return None


@router.post("/upload")
def upload(file: UploadFile = File(...)):
    file_path = f"{UPLOAD_DIR}/{file.filename}"

    # Save file in chunks
    with open(file_path, "wb+") as f:
        for chunk in file.file:
            f.write(chunk)

    def file_process_stream():
        total_size = os.path.getsize(file_path)
        chunk_size = 1024 * 1024
        try:
            with open(file_path, "rb") as f:
                total = 0
                done = False

                while not done:
                    chunk = f.read(chunk_size)
                    if not chunk:
                        done = True
                        continue

                    total += len(chunk)
                    progress = round((total / total_size) * 100, 2)

                    res = {
                        "progress": progress,
                        "total": total_size,
                        "completed": total,
                    }
                    yield f"data: {json.dumps(res)}\n\n"

                if done:
                    f.seek(0)
                    hashed = calculate_sha256(f)
                    f.seek(0)

                    url = f"{OLLAMA_API_BASE_URL}/blobs/sha256:{hashed}"
                    response = requests.post(url, data=f)

                    if response.ok:
                        res = {
                            "done": done,
                            "blob": f"sha256:{hashed}",
                            "name": file.filename,
                        }
                        os.remove(file_path)
                        yield f"data: {json.dumps(res)}\n\n"
                    else:
                        raise Exception(
                            "Ollama: Could not create blob, Please try again."
                        )

        except Exception as e:
            res = {"error": str(e)}
            yield f"data: {json.dumps(res)}\n\n"

    return StreamingResponse(file_process_stream(), media_type="text/event-stream")
