"""
企业微信机器人通知模块。
按第一版模板发送 Controller 接口参数变更通知，支持超长内容分段发送。
"""

import json
from typing import List, Optional

import requests

from comparator import EndpointChangeReport
from git_utils import CommitInfo

# 企微 text 消息字节上限约 2048，留余量按字符分段
MAX_TEXT_LENGTH = 2000


def truncate_text(text: str, max_length: int = MAX_TEXT_LENGTH) -> str:
    """
    截断文本，避免超出企微单条消息限制。

    :param text:       原始文本
    :param max_length: 最大字符数
    :return: 截断后文本
    """
    if len(text) <= max_length:
        return text
    return text[:max_length] + "\n... [消息过长，已截断]"


def build_single_endpoint_message(
    report: EndpointChangeReport,
    push_user: str,
    push_time: str,
) -> str:
    """
    按第一版模板构建单个接口的通知正文。

    模板示例：
    [API变更通知]
    URI: GET /api/users/{id}
    修改人：张三
    修改时间：2026-06-03 10:00:00
    参数变更:
      - 删除: Boolean userType
      - 新增: Boolean includeDisabled (是否必填：false)

    :param report:    单个接口变更报告
    :param push_user: 代码推送人
    :param push_time: 推送时间
    :return: 通知文本
    """
    lines = [
        "[API变更通知]",
        f"URI: {report.http_method} {report.uri}",
        f"修改人：{push_user}",
        f"修改时间：{push_time}",
    ]

    if report.is_new_endpoint:
        lines.append("接口状态：新增接口")
        if report.parameter_changes:
            lines.append("参数变更:")
            for change in report.parameter_changes:
                lines.append(change.to_display_line())
    elif report.is_removed_endpoint:
        lines.append("接口状态：已删除接口")
        lines.append("  - 整个接口已被移除")
    else:
        lines.append("参数变更:")
        for change in report.parameter_changes:
            lines.append(change.to_display_line())

    return "\n".join(lines)


def build_all_notifications(
    reports: List[EndpointChangeReport],
    push_user: str,
    push_time: str,
    llm_review: Optional[str] = None,
) -> List[str]:
    """
    将所有接口变更组装为通知消息列表，超长时自动分段。

    :param reports:     变更报告列表
    :param push_user:   推送人
    :param push_time:   推送时间
    :param llm_review:  LLM 参数变更审核结论（可选，附在最后一条或单独一条）
    :return: 待发送的消息段落列表
    """
    if not reports:
        return []

    messages: List[str] = []
    current = ""

    for report in reports:
        block = build_single_endpoint_message(report, push_user, push_time)
        separator = "\n\n---\n\n"

        if not current:
            current = block
        elif len(current) + len(separator) + len(block) <= MAX_TEXT_LENGTH:
            current += separator + block
        else:
            messages.append(current)
            current = block

    if current:
        messages.append(current)

    # LLM 审核结论单独或追加发送
    if llm_review:
        review_msg = f"[AI参数变更审核]\n修改人：{push_user}\n修改时间：{push_time}\n\n{llm_review}"
        if messages and len(messages[-1]) + len(review_msg) + 4 <= MAX_TEXT_LENGTH:
            messages[-1] += "\n\n" + review_msg
        elif len(review_msg) <= MAX_TEXT_LENGTH:
            messages.append(review_msg)
        else:
            messages.extend(_split_long_text(review_msg, MAX_TEXT_LENGTH))

    return messages


def _split_long_text(text: str, max_len: int) -> List[str]:
    """按行拆分超长文本。"""
    lines = text.split("\n")
    chunks: List[str] = []
    current = ""
    for line in lines:
        candidate = current + line + "\n"
        if len(candidate) > max_len and current:
            chunks.append(current.rstrip())
            current = line + "\n"
        else:
            current = candidate
    if current.strip():
        chunks.append(current.rstrip())
    return chunks


def _post_wecom_text(webhook_url: str, content: str) -> bool:
    """
    发送单条 text 消息到企业微信。

    :param webhook_url: Webhook URL
    :param content:     消息正文
    :return: 是否成功
    """
    if not webhook_url or "YOUR_WECOM_KEY" in webhook_url:
        print("[警告] 未配置有效的企业微信 Webhook URL。")
        print("--- 通知预览 ---")
        print(content[:800])
        return False

    payload = {
        "msgtype": "text",
        "text": {"content": truncate_text(content)},
    }

    try:
        resp = requests.post(
            webhook_url,
            headers={"Content-Type": "application/json"},
            data=json.dumps(payload, ensure_ascii=False).encode("utf-8"),
            timeout=10,
        )
        if resp.status_code == 200 and resp.json().get("errcode", 0) == 0:
            return True
        print(f"[错误] 企微返回异常: {resp.status_code} {resp.text}")
        return False
    except requests.RequestException as exc:
        print(f"[错误] 发送企微消息失败: {exc}")
        return False


def send_parameter_change_notification(
    webhook_url: str,
    reports: List[EndpointChangeReport],
    push_user: str,
    push_time: str,
    llm_review: Optional[str] = None,
    mentioned_users: Optional[List[str]] = None,
) -> int:
    """
    发送 Controller 接口参数变更通知（支持分段）。

    :param webhook_url:     企微 Webhook
    :param reports:         AST 参数变更报告
    :param push_user:       推送人
    :param push_time:       推送时间
    :param llm_review:      LLM 参数变更审核（可选）
    :param mentioned_users: @ 成员 userid 列表
    :return: 成功发送条数
    """
    if not reports and not llm_review:
        print("无接口参数变更，不发送到企业微信")
        return 0

    segments = build_all_notifications(reports, push_user, push_time, llm_review)
    if not segments:
        return 0

    sent = 0
    for i, segment in enumerate(segments):
        payload_text = segment
        if mentioned_users and i == 0:
            # text 类型 @ 成员需放在 mentioned_list
            pass  # 在 _post 里处理较复杂，首条单独带 mentioned

        if _post_wecom_text(webhook_url, payload_text):
            sent += 1
            print(f"第 {sent} 条通知已发送到企业微信")

    if sent > 0:
        print(f"总共发送 {sent} 条通知到企业微信")
    return sent