import re
from datetime import datetime, timezone

import httpx

from app.config import settings


def _extract_video_id(video_url: str) -> str | None:
    """URL에서 YouTube 비디오 ID 추출."""
    patterns = [
        r"(?:youtu\.be/)([^?&]+)",
        r"(?:v=)([^?&]+)",
    ]
    for p in patterns:
        m = re.search(p, video_url)
        if m:
            return m.group(1)
    return None


def _parse_summary(summary: str) -> dict[str, str]:
    """요약 텍스트를 섹션별로 파싱."""
    sections: dict[str, str] = {}
    current_key = None
    current_lines: list[str] = []

    for line in summary.split("\n"):
        # **한줄 요약**: ... 또는 ## 한줄 요약 형태 매칭
        header_match = re.match(
            r"^(?:##\s*|-\s*\*\*|\*\*)(한줄\s*요약|주요\s*내용|결론/?시사점)[:\*\s]*(.*)",
            line,
        )
        if header_match:
            if current_key:
                sections[current_key] = "\n".join(current_lines).strip()
            current_key = header_match.group(1).replace(" ", "")
            rest = re.sub(r"^\*\*:?\s*", "", header_match.group(2)).strip()
            current_lines = [rest] if rest else []
        elif current_key is not None:
            current_lines.append(line)

    if current_key:
        sections[current_key] = "\n".join(current_lines).strip()

    return sections


async def send_to_discord(title: str, video_url: str, summary: str) -> None:
    """Discord 웹훅으로 요약 전송 (임베드 디자인)."""
    video_id = _extract_video_id(video_url)
    thumbnail_url = (
        f"https://img.youtube.com/vi/{video_id}/hqdefault.jpg"
        if video_id
        else None
    )

    sections = _parse_summary(summary)

    oneliner = sections.get("한줄요약", "")
    main_points = sections.get("주요내용", "")
    conclusion = sections.get("결론/시사점", sections.get("결론시사점", ""))

    # 파싱 실패 시 전체 텍스트를 그대로 사용
    if not oneliner and not main_points:
        fields = [{"name": "🔗 원본 영상", "value": video_url, "inline": False}]
        description = summary[:4096]
    else:
        description = f"### 💡 {oneliner}" if oneliner else ""
        fields = []
        if main_points:
            fields.append({
                "name": "📋 주요 내용",
                "value": main_points[:1024],
                "inline": False,
            })
        if conclusion:
            fields.append({
                "name": "🎯 결론 / 시사점",
                "value": conclusion[:1024],
                "inline": False,
            })
        fields.append({
            "name": "🔗 원본 영상",
            "value": video_url,
            "inline": False,
        })

    embed = {
        "title": f"📰 {title}",
        "url": video_url,
        "description": description,
        "color": 0x2B2D31,
        "fields": fields,
        "footer": {
            "text": "YouTube 뉴스 요약 봇",
            "icon_url": "https://www.youtube.com/s/desktop/f5ced909/img/favicon_144x144.png",
        },
        "timestamp": datetime.now(timezone.utc).isoformat(),
    }

    if thumbnail_url:
        embed["thumbnail"] = {"url": thumbnail_url}

    payload = {"embeds": [embed]}

    async with httpx.AsyncClient() as client:
        resp = await client.post(settings.discord_webhook_url, json=payload)
        resp.raise_for_status()