"""Request and response shapes for conversations and their turns."""

import uuid
from datetime import datetime

from pydantic import BaseModel, ConfigDict, Field

from app.models import ConversationMode, MessageRole


class ConversationCreate(BaseModel):
    mode: ConversationMode


class ConversationSummary(BaseModel):
    model_config = ConfigDict(from_attributes=True)

    id: uuid.UUID
    title: str | None = None


class MessageSource(BaseModel):
    document_id: uuid.UUID
    title: str
    heading_path: str
    excerpt: str = ""
    # True when the passage was passed to the model; False for passages that
    # were retrieved but dropped as too weak (a no-answer turn). Old messages
    # predate the flag, so it defaults to True (they were all cited).
    used: bool = True
    # The cited document has an unanswered request to check it. Snapshotted
    # with the citation, so a reload shows what was true when it was answered.
    review_pending: bool = False


class MessageOut(BaseModel):
    model_config = ConfigDict(from_attributes=True)

    id: uuid.UUID
    role: MessageRole
    content: str
    created_at: datetime
    sources: list[MessageSource] = []
    # Set when no model answered this turn and `sources` is a plain full-text
    # result list instead: the `llm_*` code that caused it, which the frontend
    # phrases. Null on every normal turn.
    fallback: str | None = None


class ConversationDetail(ConversationSummary):
    messages: list[MessageOut] = []


class SendMessage(BaseModel):
    content: str = Field(min_length=1, max_length=8000)