import imaplib
import email
import re
from email.header import decode_header
from datetime import datetime, timezone
from email.utils import parsedate_to_datetime
import time
from datetime import datetime, timedelta


def to_utf7_imap(text):
    """
    将文本转换为 IMAP UTF-7 编码格式。

    参数：
        text (str): 要转换的文本。

    返回：
        str: 转换后的 UTF-7 编码文本。
    """
    if not text:
        return ""

    # 匹配所有非 ASCII 字符
    def encode_match(match):
        return "&" + match.group(0).encode("utf-16be").hex().upper() + "-"

    # 替换非 ASCII 字符为 UTF-7 格式
    return re.sub(r"[^\x20-\x7E]", encode_match, text)


def build_search_criteria(from_email=None, subject=None, body_keyword=None, since=None, before=None, unseen=False):
    """
    构建 IMAP 搜索条件字符串，支持简单查询逻辑。

    参数：
        from_email (str): 发件人邮箱地址。
        subject (str): 邮件标题的关键字。
        body_keyword (str): 邮件正文的关键字。
        since (datetime): 起始时间，筛选此时间之后的邮件。
        before (datetime): 截止时间，筛选此时间之前的邮件。
        unseen (bool): 是否仅筛选未读邮件。

    返回：
        str: 构建的 IMAP 搜索条件字符串。
    """
    criteria = []

    if unseen:
        criteria.append("UNSEEN")

    if from_email:
        criteria.append(f'FROM "{to_utf7_imap(from_email)}"')

    if subject:
        criteria.append(f'SUBJECT "{to_utf7_imap(subject)}"')

    if body_keyword:
        criteria.append(f'BODY "{to_utf7_imap(body_keyword)}"')

    if since:
        criteria.append(f'SINCE {since.strftime("%d-%b-%Y")}')

    if before:
        criteria.append(f'BEFORE {before.strftime("%d-%b-%Y")}')

    # 用空格拼接所有条件（IMAP 默认 AND 逻辑）
    return " ".join(criteria) if criteria else "ALL"


def parse_email_date(date_str, default_tz=timezone.utc):
    """
    安全解析邮件日期。
    """
    if not date_str:
        return None
    try:
        email_date = parsedate_to_datetime(date_str)
        if email_date and email_date.tzinfo is None:
            email_date = email_date.replace(tzinfo=default_tz)
        return email_date
    except Exception as e:
        print(f"Warning: Failed to parse date '{date_str}': {e}")
        return None


class EmailClient:
    def __init__(self, host, username, password):
        self.host = host
        self.username = username
        self.password = password
        self.connection = None

    def connect(self):
        self.connection = imaplib.IMAP4(self.host)
        self.connection.login(self.username, self.password)
        self.connection.select("inbox")

    def disconnect(self):
        if self.connection:
            self.connection.logout()

    def search_emails(self, search_criteria):
        """
        使用自由构建的搜索条件执行 IMAP 搜索。

        参数：
            search_criteria (str): 用于 IMAP 搜索的条件字符串。

        返回：
            tuple: 搜索结果 (result, data)，其中：
                   - result (str): 搜索状态 ("OK" 表示成功)。
                   - data (list): 搜索到的邮件 ID 列表。

        Raises:
            Exception: 如果搜索失败。
        """
        result, data = self.connection.search(None, search_criteria)
        if result != "OK":
            raise Exception(f"Failed to search emails with criteria: {search_criteria}")

        email_ids = data[0].split()
        if not email_ids:
            print("Debug: No matching emails found.")
            return result, []  # 返回空列表以便后续处理

        return result, data

    def fetch_recent_emails(self, from_email=None, subject=None, body_keyword=None, since=None, before=None,
                            unseen=False, max_count=100):
        """
        使用构建的搜索条件查询最近的邮件。

        参数：
            from_email (str): 发件人邮箱地址。
            subject (str): 邮件标题关键字。
            body_keyword (str): 邮件正文关键字。
            since (datetime): 起始时间。
            before (datetime): 截止时间。
            unseen (bool): 是否只查询未读邮件。
            max_count (int): 返回的邮件数量上限。

        返回：
            list: 符合条件的邮件 ID 列表，按接收时间倒序排列。
        """
        search_criteria = build_search_criteria(
            from_email=from_email,
            subject=subject,
            body_keyword=body_keyword,
            since=since,
            before=before,
            unseen=unseen
        )
        result, data = self.search_emails(search_criteria)

        # 检查 `data` 是否有效
        if not data or not data[0]:
            print("Debug: No emails found matching the criteria.")
            return []  # 返回空列表

        # 正常处理邮件 ID
        email_ids = data[0].split()[-max_count:]
        return list(reversed(email_ids))

    def fetch_all_matching_emails(self, email_ids, sender_pattern=None, keyword_pattern=None, subject_pattern=None,
                                  start_time=None, max_results=None):
        if max_results is not None and max_results <= 0:
            raise ValueError("max_results must be a positive integer or None")

        sender_regex = re.compile(sender_pattern) if sender_pattern else None
        keyword_regex = re.compile(keyword_pattern) if keyword_pattern else None
        subject_regex = re.compile(subject_pattern) if subject_pattern else None
        all_matched_emails = []

        for email_id in email_ids:
            try:
                result, data = self.connection.fetch(email_id, "(RFC822)")
                if result != "OK":
                    print(f"Warning: Failed to fetch email with ID {email_id}")
                    continue

                msg = email.message_from_bytes(data[0][1])

                from_email = email.utils.parseaddr(msg["From"])[1] if msg["From"] else ""
                if sender_regex and not sender_regex.search(from_email):
                    continue

                subject, encoding = decode_header(msg["Subject"])[0]
                subject = subject.decode(encoding or "utf-8") if isinstance(subject, bytes) else subject
                if subject_regex and not subject_regex.search(subject):
                    continue

                print("1没报错")

                content = ""
                for part in msg.walk():
                    content_type = part.get_content_type()
                    print("2没报错")
                    try:
                        if content_type == "text/plain":
                            content += part.get_payload(decode=True).decode(part.get_content_charset() or "utf-8")
                            print("3没报错")
                        elif content_type == "text/html" and not content:
                            content += part.get_payload(decode=True).decode(part.get_content_charset() or "utf-8")
                            print("4没报错")
                    except Exception as e:
                        print(f"Warning: Failed to decode {content_type} content: {e}")

                if keyword_regex and not keyword_regex.search(content):
                    continue


                date_str = msg.get("Date")
                email_date = parse_email_date(date_str) if date_str else None
                # print('email_date:',email_date)
                # print('start_time:',start_time)
                if start_time and email_date and email_date < start_time:
                    continue

                matched_email = {
                    "subject": subject,
                    "from": from_email,
                    "content": content,
                    "date": email_date
                }
                all_matched_emails.append(matched_email)

                if max_results and len(all_matched_emails) >= max_results:
                    break

            except Exception as e:
                print(f"Error: Failed to process email ID {email_id}: {e}")

        return all_matched_emails

    def filter_emails_by_sender_and_keyword(self, email_ids, sender_pattern=None, keyword_pattern=None,
                                            subject_pattern=None, start_time=None):
        matched_emails = self.fetch_all_matching_emails(
            email_ids=email_ids,
            sender_pattern=sender_pattern,
            keyword_pattern=keyword_pattern,
            subject_pattern=subject_pattern,
            start_time=start_time,
            max_results=1
        )
        return matched_emails[0] if matched_emails else None


class GoogleCodeReceiver:
    def __init__(self, email_client):
        self.email_client = email_client
        self.last_timestamp = datetime.now(timezone.utc)

    def _update_last_timestamp(self):
        self.last_timestamp = datetime.now(timezone.utc)

    def wait_code(self, username, timeout=60, interval=3, start_time=None):
        """
        等待 Google 验证码邮件。

        参数：
            username (str): 用户名，用于在正文中检索匹配邮件。
            timeout (int): 最大等待时间，单位为秒。
            interval (int): 轮询间隔，单位为秒。
            start_time (datetime): 开始检索邮件的时间。默认值为当前时间。

        返回：
            str: 提取的验证码。
        """
        # 如果未指定 `start_time`，使用当前时间
        if start_time is None:
            start_time = datetime.now(timezone.utc)  # 默认使用当前 UTC 时间
        elif start_time.tzinfo is None:
            # 如果 `start_time` 没有时区信息，假定为本地时间，并转为 UTC
            local_time = start_time.astimezone()
            start_time = local_time.astimezone(timezone.utc)
        else:
            # 如果已经有时区信息，统一转为 UTC
            start_time = start_time.astimezone(timezone.utc)

        # 确定 `since` 时间，取 `start_time` 往前推 2 天
        since = start_time - timedelta(days=2)

        # 更新 `last_timestamp`
        self._update_last_timestamp()

        end_time = datetime.now(timezone.utc) + timedelta(seconds=timeout)
        subject_pattern = r"(?:Email verification code|电子邮件验证码)[:：]?\s*(\d{6})"
        # sender_pattern = r"noreply@google\.com"
        # keyword_pattern = re.escape(username)

        while datetime.now(timezone.utc) < end_time:
            try:
                # Fetch recent emails with the adjusted `since`
                email_ids = self.email_client.fetch_recent_emails(
                    max_count=10,
                    from_email="noreply@google.com",
                    body_keyword=username,
                    since=since  # 从 `start_time` 往前推 2 天开始检索
                )

                matched_email = self.email_client.filter_emails_by_sender_and_keyword(
                    email_ids=email_ids,
                    # sender_pattern=sender_pattern,
                    # keyword_pattern=keyword_pattern,
                    subject_pattern=subject_pattern,
                    start_time=start_time  # 确保只检索 `start_time` 之后的邮件
                )

                if matched_email:
                    match = re.search(subject_pattern, matched_email["subject"])
                    if match:
                        return match.group(1)

            except Exception as e:
                print(f"Warning: Error occurred while fetching code: {e}")

            time.sleep(interval)

        raise TimeoutError("Timeout waiting for verification code.")


# 老的通用邮箱测试
def mailTest():
    server = "server-10474.cuiqiu.vip"  # 替换为你的 IMAP 服务器地址
    username = "gmailvinted@mailezu.com"
    password = "g1l2o0hld84"
    client = EmailClient(server, username, password)
    client.connect()
    start_time = datetime(2024, 11, 22)
    sender_pattern = r".*google.*"  # 使用正则表达式匹配发件人邮箱
    keyword_pattern = r".*"  # 替换为你想要匹配的关键字或正则表达式
    try:

        email_ids = client.fetch_recent_emails(
            max_count=10,
            from_email="noreply@google.com",
            # subject='Email verification code',#中文邮件叫 '电子邮件验证码‘
            body_keyword='RibeAchour875@gmail.com',
            since=start_time,
        )

        # 获取时间上最新的匹配项，应用起始时间过滤器
        latest_matched_email = client.filter_emails_by_sender_and_keyword(email_ids, sender_pattern, keyword_pattern)
        if latest_matched_email:
            print("\n时间上最新的匹配邮件:")
            print("主题:", latest_matched_email["subject"])
            print("发件人:", latest_matched_email["from"])
            print("内容:", latest_matched_email["content"])
            print("时间:", latest_matched_email["date"])
        else:
            print("没有符合条件的时间上最新的匹配邮件")

        # print(f"ids:{email_ids}")
        # 获取所有匹配的邮件，应用起始时间过滤器
        all_matched_emails = client.fetch_all_matching_emails(email_ids, sender_pattern, keyword_pattern)
        if all_matched_emails:
            print("\n所有匹配的邮件:")
            for idx, email in enumerate(all_matched_emails):
                print(f"邮件 {idx + 1}:")
                print("主题:", email["subject"])
                print("发件人:", email["from"])
                print("内容:", email["content"], "\n")  # 显示内容
                print("时间:", email["date"])
        else:
            print("没有符合条件的所有匹配邮件")

    finally:
        client.disconnect()


def codeTest():
    server = "server-10474.cuiqiu.vip"  # 替换为你的 IMAP 服务器地址
    username = "gmailvinted@mailezu.com"
    password = "g1l2o0hld84"

    client = EmailClient(server, username, password)
    client.connect()
    try:
        code_receiver = GoogleCodeReceiver(client)
        # 这里改成要捕获的目标邮件地址
        code = code_receiver.wait_code(
            username="RibeAchour875@gmail.com", timeout=300, interval=5,
            start_time=datetime(2024, 11, 10))
        # code = code_receiver.wait_code(username="RibeAchour875@gmail.com", timeout=300, interval=5)

        print(f"收到谷歌验证码: {code}")
    except TimeoutError as e:
        print(e)
    except Exception as e:
        print(f"An unexpected error occurred: {e}")
    finally:
        client.disconnect()


def test3():
    server = "server-10474.cuiqiu.vip"  # 替换为你的 IMAP 服务器地址
    username = "gmailvinted@mailezu.com"
    password = "g1l2o0hld84"

    # server = "imap.qq.com"
    # username = "bigemon@foxmail.com"
    # password =  "ejudkkdfiuemcaaj"

    client = EmailClient(server, username, password)
    client.connect()

    # mailTest()

    ok, email_ids = client.search_emails('FROM "noreply@google.com" BODY "RibeAchour875@gmail.com" SINCE 11-Nov-2024')
    if email_ids:
        print(email_ids)
        sender_pattern = r".*google.*"  # 使用正则表达式匹配发件人邮箱
        keyword_pattern = r".*"  # 替换为你想要匹配的关键字或正则表达式
        all_matched_emails = client.fetch_all_matching_emails(email_ids)
        if all_matched_emails:
            print("\n所有匹配的邮件:")
            for idx, email in enumerate(all_matched_emails):
                print(f"邮件 {idx + 1}:")
                print("主题:", email["subject"])
                print("发件人:", email["from"])
                print("内容:", email["content"], "\n")  # 显示内容
                print("时间:", email["date"])
        else:
            print("没有符合条件的所有匹配邮件")
    else:
        print("查不到")


# 使用示例
if __name__ == "__main__":
    # test3()
    codeTest()