"""Pydantic request/response schemas (API contract)."""
from __future__ import annotations

import uuid
from datetime import datetime

from pydantic import BaseModel, Field, field_validator


class HealthResponse(BaseModel):
    status: str
    db: str
    version: str
    environment: str


class SuggestionList(BaseModel):
    suggestions: list[str]


class ChatRequest(BaseModel):
    message: str = Field(min_length=1, max_length=4000)


class LoginRequest(BaseModel):
    """``POST /api/login`` body (phase 16): the single admin's password.

    An empty or wrong password is a 401 with one generic detail — never a
    422 that would hint at input-shape differences.
    """

    password: str = ""


class WhoamiResponse(BaseModel):
    """``GET /api/whoami`` (phase 16) — drives all UI gating."""

    authenticated: bool
    role: str  # "admin" | "anonymous"


class SourceRef(BaseModel):
    source: str
    path: str
    title: str


class ChatDoneEvent(BaseModel):
    """Final SSE event of a chat turn: metadata for the finished answer."""

    type: str = "done"
    deflected: bool
    sources: list[SourceRef]
    suggestions: list[str] = []


class ChatErrorEvent(BaseModel):
    """SSE error event: a turn that cannot complete (PLAN §4).

    The client's loading-feedback state machine (phase 06) keys off this
    exact shape — ``{type: "error", detail: str}`` — to flip to the error
    state and re-enable the send button.
    """

    type: str = "error"
    detail: str


class DocSummary(BaseModel):
    """One indexed document as shown on the Sources page / API."""

    id: str
    source: str
    path: str
    title: str
    chunks: int
    indexed_at: str


class DocList(BaseModel):
    """Response of ``GET /api/docs`` (empty list → designed empty state)."""

    documents: list[DocSummary]


class DocContent(BaseModel):
    """One indexed document's full content (feeds the viewer page, phase 10)."""

    source: str
    path: str
    title: str
    format: str
    content: str
    indexed_at: str
    chunks: int


class SteeringNoteIn(BaseModel):
    """``POST /api/steering`` body: one tuning instruction (phase 15).

    The note is trimmed *before* the length constraints run, so a
    whitespace-only body is a 422 and a 2000-char note with surrounding
    spaces still passes.
    """

    note: str = Field(min_length=1, max_length=2000)

    @field_validator("note", mode="before")
    @classmethod
    def _trim_note(cls, v: object) -> object:
        return v.strip() if isinstance(v, str) else v


class SteeringNote(BaseModel):
    """One stored steering note (API shape — ISO-8601 ``created_at``)."""

    id: uuid.UUID
    note: str
    created_at: datetime


class SteeringNoteList(BaseModel):
    """``GET /api/steering`` response: all notes, newest first."""

    notes: list[SteeringNote]