"""
Chat models for AI assistant conversations.
"""
from django.db import models
from core.models.base import BaseModel


class ChatConversation(BaseModel):
    """
    A chat conversation between a team member and the AI assistant.
    Conversations persist across browser sessions and can be resumed.
    """
    team_profile = models.ForeignKey(
        'TeamProfile',
        on_delete=models.CASCADE,
        related_name='chat_conversations',
        help_text="The team member who owns this conversation"
    )
    title = models.CharField(
        max_length=255,
        blank=True,
        help_text="Auto-generated title based on conversation content"
    )
    is_active = models.BooleanField(
        default=True,
        help_text="Whether this conversation is active (not archived)"
    )

    class Meta:
        ordering = ('-updated_at',)
        verbose_name = 'Chat Conversation'
        verbose_name_plural = 'Chat Conversations'

    def __str__(self):
        return f"{self.team_profile}: {self.title or 'Untitled'}"

    def generate_title(self) -> str:
        """
        Generate a title from the first user message.
        Returns the first 50 characters of the first user message.
        """
        first_message = self.messages.filter(role='user').first()
        if first_message:
            content = first_message.content[:50]
            if len(first_message.content) > 50:
                content += '...'
            return content
        return 'New Conversation'


class ChatMessage(BaseModel):
    """
    Individual message in a chat conversation.
    Stores both user messages and assistant responses, including tool calls.
    """
    ROLE_CHOICES = [
        ('user', 'User'),
        ('assistant', 'Assistant'),
    ]

    conversation = models.ForeignKey(
        ChatConversation,
        on_delete=models.CASCADE,
        related_name='messages',
        help_text="The conversation this message belongs to"
    )
    role = models.CharField(
        max_length=20,
        choices=ROLE_CHOICES,
        help_text="Whether this message is from the user or assistant"
    )
    content = models.TextField(
        blank=True,
        help_text="The text content of the message"
    )
    tool_calls = models.JSONField(
        default=list,
        blank=True,
        help_text="List of MCP tool calls made during this message"
    )
    tool_results = models.JSONField(
        default=list,
        blank=True,
        help_text="Results from MCP tool executions"
    )

    class Meta:
        ordering = ('created_at',)
        verbose_name = 'Chat Message'
        verbose_name_plural = 'Chat Messages'

    def __str__(self):
        preview = self.content[:50] + '...' if len(self.content) > 50 else self.content
        return f"[{self.role}] {preview}"