import httpx
from typing import Dict, Any, List, Union
from datetime import datetime
from app.core.biz_exception import BizLogicError
from app.schemas.wechat import WechatIn


def _parse_slots_summary(availability_data):
    """
    availability:
    [
      { "date": "2025-01-05", "times": [] },
      { "date": "2025-01-06", "times": [{"time": "09:30"}] }
    ]
    """
    if not availability_data:
        return "No specific slots data."
    
    if not isinstance(availability_data, list):
        return str(availability_data)
        
    summaries = []
    # 限制显示天数，防止消息过长
    display_limit = 4 
    
    for day in availability_data[:display_limit]:
        date_str = day.get("date")
        
        times = day.get("times", [])
        
        if not times:
            # 修改点：即使没有具体时间，只要有日期条目，也显示为可用
            summaries.append(f"{date_str}")
        else:
            # 有具体时间的处理
            time_list = [t.get("time", "") for t in times[:5]]
            time_text = ", ".join(filter(None, time_list)) # 过滤空时间
            if len(times) > 5:
                time_text += f" (+{len(times) - 5})"
            summaries.append(f"{date_str}: {time_text}")
            
    if len(availability_data) > display_limit:
        summaries.append(f"(+{len(availability_data) - display_limit} more days)")
        
    return " | ".join(summaries)


def _get_display_meta(slot_snapshot):
    """
    Return dynamic header logic based on status.
    """
    # 修复：确保这里也调用增强后的日期格式化
    date_str = slot_snapshot.get("earliest_date")
    
    status = slot_snapshot.get("availability_status")
    country = slot_snapshot.get("country", "Unknown")
    city = slot_snapshot.get("city", "Unknown")

    if status == 'Available':
        emoji = "🟢"
        headline = f'{country}, {city}: {date_str}'
        color = "info" # Green
    elif status == 'Waitlist':
        emoji = "🟡"
        headline = f'Waitlist: {country}, {city}'
        color = "warning" # Orange
    else:
        emoji = "🔴"
        headline = f'No Slots: {country}, {city}'
        color = "comment" # Grey
        
    return emoji, headline, color, date_str

class WechatService:
    
    @staticmethod
    async def _send_webhook(api_token: str, payload: Dict[str, Any]):
        """内部私有方法：发送 HTTP 请求到企业微信 Webhook"""
        url = f"https://qyapi.weixin.qq.com/cgi-bin/webhook/send?key={api_token}"

        try:
            async with httpx.AsyncClient(timeout=10) as client:
                response = await client.post(url, json=payload)
        except httpx.RequestError as e:
            raise BizLogicError(f"Wechat push request error: {e}")

        if response.status_code != 200:
            raise BizLogicError(f"Wechat push failed, http_status={response.status_code}")

        data = response.json()
        if data.get("errcode") != 0:
            raise BizLogicError(
                f"Wechat push failed, errcode={data.get('errcode')}, errmsg={data.get('errmsg')}"
            )
        return True

    @staticmethod
    async def push_markdown(api_token: str, content: str):
        """发送 Markdown 消息"""
        body = {
            "msgtype": "markdown",
            "markdown": {
                "content": content
            }
        }
        return await WechatService._send_webhook(api_token, body)

    @staticmethod
    async def push_slot_snapshot(api_token: str, slot_snapshot: Dict[str, Any]):
        # 获取元数据
        emoji, headline, color, date_str = _get_display_meta(slot_snapshot)
        
        # 解析详情
        slots_summary = _parse_slots_summary(slot_snapshot.get("availability"))
        
        # 处理可能的 None 值
        website = slot_snapshot.get("website") or "#"  # 如果没有网址，给一个空锚点
        # 格式化更新时间
        updated_at = slot_snapshot.get("snapshot_at", "")
        if "T" in str(updated_at):
             updated_at = str(updated_at).replace("T", " ")

        TEMPLATE = (
            "# {emoji} {headline}\n"
            "> **Visa Type**: <font color=\"comment\">{visa_type}</font>\n"
            "> **Earliest**: <font color=\"{color}\">{date_str}</font>\n"
            "> **Details**: <font color=\"comment\">{slots_summary}</font>\n"
            "\n"
            "👉 [Tap to Book Appointment]({website})\n"
            "\n"
            "<font color=\"comment\">Updated: {updated_at}</font>"
        )

        markdown_content = TEMPLATE.format_map({
            "emoji": emoji,
            "headline": headline,
            "visa_type": slot_snapshot.get("visa_type", "N/A"),
            "color": color,
            "date_str": date_str,
            "slots_summary": slots_summary,
            "website": website,
            "updated_at": updated_at,
        })
        
        return await WechatService.push_markdown(api_token, markdown_content)