"""Request/response schemas.

NFR-MAINT-01 契约先行: schema 先定义，客户端类型由 OpenAPI 生成。
Wire responses are wrapped by the unified envelope (架构文档 §9.2); these models
describe the ``data`` payload only.
"""

from __future__ import annotations

from datetime import datetime

from pydantic import BaseModel, Field


class DevTokenRequest(BaseModel):
    device_key: str = Field(
        default="local-dev",
        min_length=1,
        max_length=64,
        description="任意稳定字符串；同一 device_key 复用同一测试用户",
    )


class DevTokenResponse(BaseModel):
    access_token: str
    token_type: str = "Bearer"
    expires_in: int
    user_id: str = Field(description="雪花 ID 以字符串返回，避免 JS 精度丢失")


class ChatRequest(BaseModel):
    message: str = Field(min_length=1, max_length=2000)
    conversation_id: str | None = Field(
        default=None,
        max_length=32,
        description="会话 ID（字符串；雪花 ID 超 2^53，JS Number 会丢精度）。"
        "缺省时新建会话并在响应中返回 (FR-AGT-09)",
    )
    request_key: str | None = Field(
        default=None,
        max_length=128,
        description="幂等键；相同键不会重复扣配额 (架构文档 §9.1)",
    )


class ConversationResponse(BaseModel):
    conversation_id: str = Field(description="雪花 ID 以字符串返回，避免 JS 精度丢失")
    title: str
    message_count: int
    last_message_at: datetime | None
    created_at: datetime


class ChatMessageItem(BaseModel):
    message_id: str
    role: str
    content: str
    model: str | None
    call_id: str | None = Field(
        description="assistant 消息关联的 ob_ai_call 行（复盘锚点）；user 消息为 null"
    )
    created_at: datetime


class ChatUsage(BaseModel):
    tokens_in: int
    tokens_out: int
    tokens_cached: int
    latency_ms: int
    cost_cents: str


class ChatResponse(BaseModel):
    conversation_id: str
    reply: str
    provider: str
    model: str
    prompt_id: str | None
    prompt_version: str | None
    call_id: str
    usage: ChatUsage
    quota_remaining: int


class QuotaResponse(BaseModel):
    quota_key: str
    period_key: str
    used: int
    limit_value: int
    bonus_granted: int
    remaining: int
    reset_at: datetime | None


class LedgerEntry(BaseModel):
    tx_id: str
    delta: int
    tx_type: str
    status: str
    reason: str | None
    quota_key: str | None
    period_key: str | None
    balance_after: int
    created_at: datetime


class TaskSubmitRequest(BaseModel):
    echo: str = Field(default="ping", max_length=200)
    idempotency_key: str | None = Field(default=None, max_length=128)


class TaskResponse(BaseModel):
    task_id: str
    task_type: str
    status: str
    progress: int
    stage_text: str | None
    result: dict[str, object] | None
    error_code: int | None
    error_message: str | None
    retry_count: int
    submitted_at: datetime
    started_at: datetime | None
    finished_at: datetime | None