#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
透過測試 IMAP 連線來推測 SMTP 設定
"""

import imaplib
import smtplib
import socket
import pytest

def _probe_imap_server(host, port=993):
    """測試 IMAP 伺服器連線"""
    ok = True
    try:
        print(f"📥 測試 IMAP: {host}:{port}")
        imap = imaplib.IMAP4_SSL(host, port, timeout=5)
        print(f"   ✅ IMAP 伺服器存在且可連接！")
        imap.logout()
        ok = True
    except socket.gaierror:
        print(f"   ❌ DNS 解析失敗")
        ok = False
    except Exception as e:
        print(f"   ⚠️  {type(e).__name__}: {e}")
        ok = False

    return ok


def test_imap_server(host, port=993):
    """測試 IMAP 伺服器連線"""
    if not _probe_imap_server(host, port):
        pytest.skip(f"IMAP 無法連線：{host}:{port}")

def guess_smtp_from_imap(imap_host):
    """從 IMAP 主機推測 SMTP 主機"""
    # 常見的對應關係
    mappings = [
        imap_host.replace('imap', 'smtp'),
        imap_host.replace('mail', 'smtp'),
        imap_host.replace('ms', 'smtp'),
        imap_host,  # 有些伺服器 IMAP 和 SMTP 用同一個
    ]
    return list(set(mappings))  # 去重

def _probe_smtp_server(host, port):
    """測試 SMTP 伺服器"""
    ok = True
    try:
        print(f"   測試 SMTP: {host}:{port} ... ", end='')
        server = smtplib.SMTP(host, port, timeout=5)
        server.ehlo()
        if server.has_extn('STARTTLS'):
            server.starttls()
            print(f"✅ 成功（支援 STARTTLS）")
            server.quit()
            ok = True
        else:
            print(f"✅ 成功（不支援加密）")
            server.quit()
            ok = True
    except Exception as e:
        print(f"❌ {type(e).__name__}")
        ok = False

    return ok


def test_smtp_server(host, port):
    """測試 SMTP 伺服器"""
    if not _probe_smtp_server(host, port):
        pytest.skip(f"SMTP 無法連線：{host}:{port}")

def main():
    print("=" * 80)
    print("🔍 PChome 郵件伺服器探測")
    print("=" * 80)

    # 嘗試常見的 PChome IMAP 伺服器
    imap_servers = [
        'imap.pchome.tw',
        'imap.pchome.com.tw',
        'mail.pchome.tw',
        'mail.pchome.com.tw',
        'ms1.pchome.tw',
        'ms1.pchome.com.tw',
    ]

    print("\n1️⃣ 測試 IMAP 伺服器（接收郵件）")
    print("-" * 80)

    found_imap = None
    for imap_host in imap_servers:
        if _probe_imap_server(imap_host):
            found_imap = imap_host
            break

    if not found_imap:
        print("\n❌ 找不到可用的 IMAP 伺服器")
        print("\n這可能表示：")
        print("   1. PChome 郵件伺服器只能在內部網路訪問")
        print("   2. 需要連接 VPN")
        print("   3. 伺服器名稱不是常見格式")
        return

    print(f"\n✅ 找到 IMAP 伺服器: {found_imap}")

    # 根據 IMAP 推測 SMTP
    print("\n2️⃣ 根據 IMAP 推測 SMTP 伺服器（發送郵件）")
    print("-" * 80)

    smtp_guesses = guess_smtp_from_imap(found_imap)
    smtp_ports = [587, 25, 465]

    found_smtp = None
    for smtp_host in smtp_guesses:
        print(f"\n嘗試: {smtp_host}")
        for port in smtp_ports:
            if _probe_smtp_server(smtp_host, port):
                found_smtp = (smtp_host, port)
                break
        if found_smtp:
            break

    print("\n" + "=" * 80)
    print("📊 測試結果")
    print("=" * 80)

    if found_smtp:
        print(f"\n🎉 找到可用的 SMTP 設定！")
        print(f"\n建議的 .env 設定：")
        print(f"   EMAIL_HOST={found_smtp[0]}")
        print(f"   EMAIL_PORT={found_smtp[1]}")
        print(f"   EMAIL_HOST_USER=yingpin_chen@pchome.tw")
        print(f"   EMAIL_HOST_PASSWORD=您的郵件密碼")
        print(f"   EMAIL_SENDER=yingpin_chen@pchome.tw")
    else:
        print(f"\n⚠️  找到 IMAP 但找不到 SMTP")
        print(f"\n建議：")
        print(f"   1. 檢查 Outlook/郵件客戶端的「寄件伺服器」設定")
        print(f"   2. 詢問 IT 部門 SMTP 伺服器地址")
        print(f"   3. 或暫時使用 Gmail 進行測試")

if __name__ == '__main__':
    main()