from django.db import models
from apps.accounts.models import User
import json
import os
from django.utils import timezone
import uuid

class GmailCredential(models.Model):
    user = models.ForeignKey(User, on_delete=models.CASCADE, related_name='gmail_credentials')
    email = models.EmailField(unique=True, help_text="Gmail email address")
    credentials = models.TextField(help_text="Serialized OAuth2 credentials (JSON)")
    is_default = models.BooleanField(default=False, help_text="Default Gmail account for user")
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)
    is_valid = models.BooleanField(default=True, help_text="Whether the credential is valid")
    last_history_id = models.CharField(max_length=50, blank=True, null=True, help_text="Last processed Gmail history ID")

    class Meta:
        unique_together = ('user', 'email')

    def set_credentials(self, credentials):
        self.credentials = json.dumps({
            'token': credentials.token,
            'refresh_token': credentials.refresh_token,
            'token_uri': credentials.token_uri,
            'client_id': credentials.client_id,
            'client_secret': credentials.client_secret,
            'scopes': credentials.scopes
        })
        self.is_valid = True

    def get_credentials(self):
        from google.oauth2.credentials import Credentials
        creds_data = json.loads(self.credentials)
        return Credentials(
            token=creds_data['token'],
            refresh_token=creds_data['refresh_token'],
            token_uri=creds_data['token_uri'],
            client_id=creds_data['client_id'],
            client_secret=creds_data['client_secret'],
            scopes=creds_data['scopes']
        )

    def __str__(self):
        return f"{self.user.username} - {self.email}"

class GmailConversation(models.Model):
    """Gmail对话记录，跟踪用户和达人之间的邮件交互"""
    user = models.ForeignKey(User, on_delete=models.CASCADE, related_name='gmail_conversations')
    user_email = models.EmailField(help_text="用户Gmail邮箱")
    influencer_email = models.EmailField(help_text="达人Gmail邮箱")
    conversation_id = models.CharField(max_length=100, unique=True, help_text="关联到chat_history的会话ID")
    title = models.CharField(max_length=100, default="Gmail对话", help_text="对话标题")
    last_sync_time = models.DateTimeField(default=timezone.now, help_text="最后同步时间")
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)
    is_active = models.BooleanField(default=True)
    metadata = models.JSONField(default=dict, blank=True, null=True, help_text="存储额外信息，如已处理的消息ID等")
    
    def __str__(self):
        return f"{self.user.username}: {self.user_email} - {self.influencer_email}"
    
    class Meta:
        ordering = ['-updated_at']
        unique_together = ('user', 'user_email', 'influencer_email')

class GmailAttachment(models.Model):
    """Gmail附件记录"""
    conversation = models.ForeignKey(GmailConversation, on_delete=models.CASCADE, related_name='attachments')
    email_message_id = models.CharField(max_length=100, help_text="Gmail邮件ID")
    attachment_id = models.CharField(max_length=100, help_text="Gmail附件ID")
    filename = models.CharField(max_length=255, help_text="原始文件名")
    file_path = models.CharField(max_length=255, help_text="保存在服务器上的路径")
    content_type = models.CharField(max_length=100, help_text="MIME类型")
    size = models.IntegerField(default=0, help_text="文件大小(字节)")
    sender_email = models.EmailField(help_text="发送者邮箱")
    chat_message_id = models.CharField(max_length=100, blank=True, null=True, help_text="关联到ChatHistory的消息ID")
    created_at = models.DateTimeField(auto_now_add=True)
    
    def __str__(self):
        return f"{self.filename} ({self.size} bytes)"
    
    def get_file_extension(self):
        """获取文件扩展名"""
        _, ext = os.path.splitext(self.filename)
        return ext.lower()
    
    def get_absolute_url(self):
        """获取文件URL"""
        return f"/media/gmail_attachments/{os.path.basename(self.file_path)}"
    
    class Meta:
        ordering = ['-created_at']

class ConversationSummary(models.Model):
    """Gmail对话摘要模型，用于持久化存储对话摘要"""
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    conversation = models.OneToOneField('GmailConversation', on_delete=models.CASCADE, related_name='summary')
    content = models.TextField(verbose_name='摘要内容')
    last_message_id = models.CharField(max_length=255, verbose_name='最后处理的消息ID或ChatHistory的ID', null=True, blank=True)
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)
    
    class Meta:
        db_table = 'gmail_conversation_summaries'
        verbose_name = 'Gmail对话摘要'
        verbose_name_plural = 'Gmail对话摘要'
        
    def __str__(self):
        return f"对话 {self.conversation.id} 摘要"