from __future__ import annotations

import logging
import os
import tempfile
from pathlib import Path

import httpx

from yuxi.channel.extensions.imessage.errors import IMessageMediaError

logger = logging.getLogger(__name__)

DEFAULT_MEDIA_MAX_MB = 16


async def download_media(
    media_url: str,
    max_mb: int = DEFAULT_MEDIA_MAX_MB,
    temp_dir: str | None = None,
) -> tuple[bytes, str, str]:
    async with httpx.AsyncClient(timeout=httpx.Timeout(60.0)) as client:
        resp = await client.get(media_url)
        resp.raise_for_status()
        data = resp.content

    size_mb = len(data) / (1024 * 1024)
    if size_mb > max_mb:
        raise IMessageMediaError(
            f"Media size {size_mb:.1f}MB exceeds limit of {max_mb}MB"
        )

    content_type = resp.headers.get("content-type", "application/octet-stream")
    ext = _guess_extension(content_type)
    filename = f"imessage_media_{os.urandom(8).hex()}{ext}"

    write_dir = temp_dir or tempfile.gettempdir()
    filepath = os.path.join(write_dir, filename)
    Path(filepath).write_bytes(data)

    return data, content_type, filepath


def cleanup_temp_file(filepath: str) -> None:
    try:
        os.unlink(filepath)
    except OSError:
        pass


async def download_attachment_via_api(
    attachment_guid: str,
    server_url: str,
    password: str,
    max_mb: int = DEFAULT_MEDIA_MAX_MB,
) -> tuple[bytes, str]:
    async with httpx.AsyncClient(timeout=httpx.Timeout(60.0)) as client:
        resp = await client.get(
            f"{server_url}/api/v1/attachment/{attachment_guid}/download",
            headers={"Password": password},
        )
        resp.raise_for_status()
        data = resp.content

    size_mb = len(data) / (1024 * 1024)
    if size_mb > max_mb:
        raise IMessageMediaError(
            f"Attachment size {size_mb:.1f}MB exceeds limit of {max_mb}MB"
        )

    content_type = resp.headers.get("content-type", "application/octet-stream")
    return data, content_type


async def download_attachment_chunked(
    attachment_guid: str,
    server_url: str,
    password: str,
    chunk_size: int = 1024 * 1024,
) -> bytes:
    async with httpx.AsyncClient(timeout=httpx.Timeout(300.0)) as client:
        resp = await client.get(
            f"{server_url}/api/v1/attachment/{attachment_guid}/chunk",
            headers={"Password": password},
        )
        resp.raise_for_status()
        return resp.content


def _guess_extension(content_type: str) -> str:
    ext_map = {
        "image/jpeg": ".jpg",
        "image/png": ".png",
        "image/gif": ".gif",
        "image/heic": ".heic",
        "image/heif": ".heif",
        "audio/mpeg": ".mp3",
        "audio/aac": ".aac",
        "audio/wav": ".wav",
        "video/mp4": ".mp4",
        "video/quicktime": ".mov",
        "application/pdf": ".pdf",
    }
    return ext_map.get(content_type, ".bin")