from datetime import datetime

from pydantic import BaseModel, ConfigDict, Field, field_validator


# 保留供其他地方使用
def _empty_to_null(value):
    """将空字符串转为 None，避免 Pydantic 校验失败。"""
    if value == "" or value == "null":
        return None
    return value


class ApiKeyCallableModel(BaseModel):
    """API Key 可调用模型配置。支持 camelCase 和 snake_case 两种字段名。"""

    model_config = ConfigDict(populate_by_name=True)

    engine_type: str = Field(..., description="video | image", alias="engineType")
    engine_id: str = Field(..., description="引擎ID", alias="engineId")
    model_name: str = Field(..., description="模型名称", alias="modelName")


class ApiKeyCreateRequest(BaseModel):
    """创建 API Key 请求。支持 camelCase 和 snake_case 两种字段名。"""

    model_config = ConfigDict(populate_by_name=True)

    company_name: str = Field(..., max_length=128, description="公司名称", alias="companyName")
    description: str | None = Field(None, description="备注")
    callable_models: list[ApiKeyCallableModel] = Field(
        default_factory=list, description="可调用模型列表", alias="callableModels",
    )
    quota_limit: float | None = Field(None, description="配额总量，NULL=无限", alias="quotaLimit")
    quota_cycle: str | None = Field(None, description="daily | monthly | one_time | NULL=无限", alias="quotaCycle")
    valid_from: datetime | None = Field(None, description="生效时间", alias="validFrom")
    valid_until: datetime | None = Field(None, description="过期时间", alias="validUntil")
    max_concurrent_video_tasks: int | None = Field(
        None, description="最大并发视频任务数", alias="maxConcurrentVideoTasks",
    )

    @field_validator("valid_from", "valid_until", mode="before")
    @classmethod
    def empty_str_to_none(cls, v):
        if v == "" or v == "null" or v == 0:
            return None
        return v


class ApiKeyUpdateRequest(BaseModel):
    """更新 API Key 请求。支持 camelCase 和 snake_case 两种字段名。"""

    model_config = ConfigDict(populate_by_name=True)

    company_name: str | None = Field(None, max_length=128, alias="companyName")
    description: str | None = None
    callable_models: list[ApiKeyCallableModel] | None = Field(None, alias="callableModels")
    quota_limit: float | None = Field(None, alias="quotaLimit")
    quota_cycle: str | None = Field(None, alias="quotaCycle")
    valid_from: datetime | None = Field(None, alias="validFrom")
    valid_until: datetime | None = Field(None, alias="validUntil")
    max_concurrent_video_tasks: int | None = Field(None, alias="maxConcurrentVideoTasks")
    is_active: bool | None = Field(None, alias="isActive")

    @field_validator("valid_from", "valid_until", mode="before")
    @classmethod
    def empty_str_to_none(cls, v):
        if v == "" or v == "null" or v == 0:
            return None
        return v


class ApiKeyResponse(BaseModel):
    """API Key 详情响应。"""

    id: str
    company_name: str
    api_key_prefix: str = Field(..., description="Key 前缀，如 vk_xxxx****")
    description: str | None
    callable_models: list[ApiKeyCallableModel]
    quota_limit: float | None
    quota_cycle: str | None
    quota_used: float
    valid_from: datetime | None
    valid_until: datetime | None
    max_concurrent_video_tasks: int | None
    is_active: bool
    last_used_at: datetime | None
    created_at: datetime
    updated_at: datetime

    model_config = ConfigDict(from_attributes=True)


class ApiKeyCreateResponse(BaseModel):
    """创建 API Key 响应（包含完整明文 Key，仅此一次）。"""

    id: str
    company_name: str
    api_key: str = Field(..., description="完整 API Key，仅创建时返回一次")
    api_key_prefix: str
    valid_until: datetime | None
    created_at: datetime


class ApiKeyRevealResponse(BaseModel):
    """揭秘 API Key 响应（随时可获取明文）。"""

    id: str
    company_name: str
    api_key: str = Field(..., description="完整 API Key")
    api_key_prefix: str


class ApiKeyListItem(BaseModel):
    """API Key 列表项。"""

    id: str
    company_name: str
    api_key_prefix: str
    description: str | None
    callable_models: list[ApiKeyCallableModel] = []
    quota_limit: float | None
    quota_cycle: str | None
    quota_used: float
    is_active: bool
    valid_from: datetime | None
    valid_until: datetime | None
    max_concurrent_video_tasks: int | None
    last_used_at: datetime | None
    created_at: datetime

    model_config = ConfigDict(from_attributes=True)


class ApiKeyQuotaAdjustRequest(BaseModel):
    """配额调整请求。支持 camelCase 和 snake_case 两种字段名。"""

    model_config = ConfigDict(populate_by_name=True)

    action: str = Field(
        ...,
        pattern=r"^(adjust|reset_usage|set_limit|change_cycle)$",
        description="adjust=增加总额 | reset_usage=重置已用 | set_limit=设置限额 | change_cycle=修改周期",
    )
    quota_limit_delta: float | None = Field(None, ge=0, description="增加总额时的增量", alias="quotaLimitDelta")
    quota_limit: float | None = Field(None, description="设置新限额时的值（NULL=无限）", alias="quotaLimit")
    quota_cycle: str | None = Field(None, description="修改周期时的值", alias="quotaCycle")
    reason: str | None = Field(None, max_length=500, description="调整原因/备注")


class ApiKeyListOut(BaseModel):
    """API Key 列表响应。"""

    total: int
    items: list[ApiKeyListItem]