"""
配置 Schema 定义

使用 Pydantic 验证配置文件的类型安全
"""

from pydantic import BaseModel, Field, field_validator, model_validator
from typing import Optional, Dict, List, Literal
from enum import Enum
from datetime import date


# ============================================================
# 枚举类型
# ============================================================

# 注意：不再使用 MarketType 枚举，改用字符串类型的 group 字段
# group 字段用于策略分组（组内竞争，强制分散）


class FactorType(str, Enum):
    """因子类型枚举"""
    MOMENTUM = "momentum"
    SLOPE_R2 = "slope_r2"
    WEIGHTED_MOMENTUM = "weighted_momentum"


class PremiumMode(str, Enum):
    """溢价控制模式"""
    FILTER = "filter"                 # 完全排除
    PENALIZE = "penalize"             # 降权


class ThresholdMode(str, Enum):
    """阈值模式"""
    FIXED = "fixed"                   # 固定阈值
    DYNAMIC = "dynamic"               # 动态阈值


class DataSourceType(str, Enum):
    """数据源类型"""
    FLASK_API = "flask_api"
    TUSHARE = "tushare"
    YFINANCE = "yfinance"


# ============================================================
# 资产池 Schema（扁平化设计）
# ============================================================

class PremiumConfig(BaseModel):
    """溢价控制配置"""
    enabled: bool = Field(default=True, description="是否启用")
    threshold: float = Field(default=0.10, ge=0, le=1.0, description="溢价阈值")


class AssetConfig(BaseModel):
    """
    标的配置（通用，支持所有场景）
    
    场景 1：指数信号 → 指数收益
      signal_source: "NDX"
      trade_source: "NDX"
    
    场景 2：指数信号 → ETF收益
      signal_source: "NDX"
      trade_source: "513100.SH"
    
    场景 3：ETF信号 → ETF收益
      signal_source: "518880.SH"
      trade_source: "518880.SH"
    
    场景 4：个股信号 → 个股收益
      signal_source: "AAPL"
      trade_source: "AAPL"
    """
    name: str = Field(..., description="标的名称")
    group: str = Field(..., description="策略分组（组内竞争，强制分散）")
    
    # 核心字段：信号来源和交易来源
    signal_source: str = Field(..., description="信号来源代码（计算因子用）")
    trade_source: str = Field(..., description="交易来源代码（计算收益用）")
    
    # 可选字段
    description: Optional[str] = Field(None, description="标的描述")
    etf: Optional[str] = Field(None, description="ETF代码（兼容旧配置）")
    premium_control: Optional["PremiumConfig"] = Field(None, description="溢价控制配置")
    
    @property
    def is_cross_market(self) -> bool:
        """是否跨市场（信号和交易不同）"""
        return self.signal_source != self.trade_source


class AssetPool(BaseModel):
    """
    资产池（扁平化设计）
    
    优势：
    1. 不预设分类，支持任意策略分组
    2. 通过 group 字段自动分组
    3. 配置简单直观
    4. 易于扩展新分组
    
    示例:
        asset_pool:
          assets:
            "NDX":
              name: "纳指100"
              group: "US_TECH"
              signal_source: "NDX"
              trade_source: "513100.SH"
            
            "BTC":
              name: "比特币"
              group: "CRYPTO"
              signal_source: "BTC"
              trade_source: "BTC"
    """
    assets: Dict[str, AssetConfig] = Field(
        default_factory=dict,
        description="所有标的（flat结构）"
    )
    
    @property
    def by_group(self) -> Dict[str, Dict[str, AssetConfig]]:
        """按策略分组"""
        groups = {}
        for code, asset in self.assets.items():
            group = asset.group
            if group not in groups:
                groups[group] = {}
            groups[group][code] = asset
        return groups
    
    @property
    def groups(self) -> list:
        """获取所有策略分组"""
        return list(self.by_group.keys())
    
    def get_signal_codes(self, group: str = None) -> list:
        """
        获取信号标的
        
        Args:
            group: 可选，过滤特定分组（如 'US_TECH'）
        """
        if group:
            return [
                asset.signal_source 
                for asset in self.assets.values()
                if asset.group == group
            ]
        return [asset.signal_source for asset in self.assets.values()]
    
    def get_trade_codes(self, group: str = None) -> list:
        """获取交易标的"""
        if group:
            return [
                asset.trade_source 
                for asset in self.assets.values()
                if asset.group == group
            ]
        return [asset.trade_source for asset in self.assets.values()]
    
    def get_signal_to_trade_mapping(self, group: str = None) -> Dict[str, str]:
        """获取信号→交易映射"""
        mapping = {}
        for asset in self.assets.values():
            if group and asset.group != group:
                continue
            mapping[asset.signal_source] = asset.trade_source
        return mapping
    
    def count(self, group: str = None) -> int:
        """获取标的数量"""
        if group:
            return len([a for a in self.assets.values() if a.group == group])
        return len(self.assets)
    
    @field_validator('assets')
    @classmethod
    def check_non_empty(cls, v):
        """至少配置一个标的"""
        if not v:
            import warnings
            warnings.warn("资产池为空")
        return v


# ============================================================
# 因子配置 Schema
# ============================================================

class FactorConfig(BaseModel):
    """因子配置"""
    type: FactorType = Field(default=FactorType.WEIGHTED_MOMENTUM, description="因子类型")
    n_days: int = Field(default=25, ge=5, le=250, description="动量窗口期（天数）")
    
    # 动态周期参数
    auto_day: bool = Field(default=False, description="是否启用动态周期")
    min_days: int = Field(default=20, ge=5, le=100, description="最小周期")
    max_days: int = Field(default=60, ge=20, le=250, description="最大周期")


# ============================================================
# 阈值配置 Schema
# ============================================================

class DynamicThresholdConfig(BaseModel):
    """动态阈值配置"""
    reference: str = Field(..., description="参考标的代码")
    ratio: float = Field(default=1.0, gt=0, description="倍数")
    fallback_enabled: bool = Field(default=True, description="参考不可用时是否回退")
    fallback_value: float = Field(default=0.0, description="回退值")


class ThresholdConfig(BaseModel):
    """阈值配置（统一 V2/V3）"""
    mode: ThresholdMode = Field(default=ThresholdMode.DYNAMIC, description="阈值模式")
    fixed_value: float = Field(default=0.0, description="固定阈值（mode=fixed时使用）")
    dynamic: Optional[DynamicThresholdConfig] = Field(None, description="动态阈值（mode=dynamic时使用）")
    
    @model_validator(mode='after')
    def validate_dynamic_config(self):
        """验证动态阈值配置"""
        if self.mode == ThresholdMode.DYNAMIC and self.dynamic is None:
            raise ValueError("dynamic 模式必须配置 dynamic 字段")
        return self


# ============================================================
# 轮动配置 Schema
# ============================================================

class GroupConfig(BaseModel):
    """策略分组配置（用于分散化选股）"""
    group: str = Field(..., description="策略分组名称")
    select_num: int = Field(default=1, ge=1, le=10, description="该分组选股数量")


class RotationConfig(BaseModel):
    """
    轮动配置
    
    支持两种选股模式：
    1. 全局选股：diversified=false，直接选 Top-N
    2. 分散化选股：diversified=true，按策略分组选股
    """
    select_num: int = Field(default=3, ge=1, le=20, description="选股数量（全局模式）")
    diversified: bool = Field(default=False, description="是否分散化选股")
    
    # 分散化配置（可选）
    diversification_groups: Optional[List[GroupConfig]] = Field(
        None,
        description="分散化分组配置（diversified=true时使用）"
    )
    
    threshold: ThresholdConfig = Field(
        default_factory=ThresholdConfig,
        description="动量阈值"
    )


# ============================================================
# 调仓配置 Schema
# ============================================================

class RebalanceConfig(BaseModel):
    """调仓配置"""
    min_hold_days: int = Field(default=1, ge=1, le=30, description="最低持有天数")
    score_threshold: float = Field(default=0.0, ge=0, le=0.5, description="调仓得分阈值（%）")
    trade_cost: float = Field(default=0.001, ge=0, le=0.01, description="单次换仓成本")


# ============================================================
# 溢价控制 Schema
# ============================================================

class MarketPremiumOverride(BaseModel):
    """市场溢价覆盖配置"""
    enabled: bool = Field(default=True, description="是否启用")
    threshold: float = Field(default=0.10, ge=0, le=1.0, description="溢价阈值")


class PremiumControlConfig(BaseModel):
    """溢价控制配置"""
    enabled: bool = Field(default=True, description="是否启用溢价控制")
    default_threshold: float = Field(default=0.10, ge=0, le=1.0, description="默认溢价阈值")
    mode: PremiumMode = Field(default=PremiumMode.FILTER, description="控制模式")
    penalty_factor: float = Field(default=0.5, ge=0, le=1.0, description="降权惩罚系数")
    
    # 按市场覆盖
    market_overrides: Dict[str, MarketPremiumOverride] = Field(
        default_factory=dict,
        description="按市场覆盖配置"
    )


# ============================================================
# 数据源配置 Schema
# ============================================================

class DataSourceConfig(BaseModel):
    """单个数据源配置"""
    type: DataSourceType = Field(..., description="数据源类型")
    enabled: bool = Field(default=True, description="是否启用")
    timeout: int = Field(default=120, ge=10, le=600, description="超时时间（秒）")
    
    # Flask API 特定配置
    url: Optional[str] = Field(None, description="API地址（flask_api使用）")
    
    # Tushare 特定配置
    token: Optional[str] = Field(None, description="Tushare Token（tushare使用）")


class DataConfig(BaseModel):
    """数据配置"""
    sources: List[DataSourceConfig] = Field(..., description="数据源列表（按优先级排序）")
    use_cache: bool = Field(default=True, description="是否使用本地缓存")
    cache_dir: str = Field(default="data_cache", description="缓存目录")
    
    @field_validator('sources')
    @classmethod
    def check_at_least_one(cls, v):
        """至少配置一个数据源"""
        if not v:
            raise ValueError("必须配置至少一个数据源")
        return v


# ============================================================
# 基准配置 Schema
# ============================================================

class BenchmarkConfig(BaseModel):
    """基准配置"""
    code: str = Field(..., description="基准代码")
    name: str = Field(..., description="基准名称")


# ============================================================
# 回测配置 Schema
# ============================================================

class BacktestConfig(BaseModel):
    """回测配置"""
    start_date: str = Field(..., description="回测起始日期（YYYY-MM-DD）")
    end_date: Optional[str] = Field(None, description="回测结束日期（None表示至今）")


# ============================================================
# 元数据 Schema
# ============================================================

class MetadataConfig(BaseModel):
    """配置元数据"""
    version: str = Field(default="1.0.0", description="配置版本")
    strategy: str = Field(default="rotation", description="策略名称")
    description: str = Field(default="", description="配置描述")
    last_updated: Optional[str] = Field(None, description="最后更新日期")


# ============================================================
# 完整策略配置 Schema
# ============================================================

class RotationStrategyConfig(BaseModel):
    """
    ETF轮动策略完整配置
    
    使用示例:
        from framework_v2.config.schemas import RotationStrategyConfig
        import yaml
        
        with open('config/rotation.yaml') as f:
            config_dict = yaml.safe_load(f)
        
        config = RotationStrategyConfig(**config_dict)
    """
    metadata: MetadataConfig = Field(default_factory=MetadataConfig, description="元数据")
    
    # 资产池
    asset_pools: AssetPool = Field(..., description="资产池配置")
    
    # 基准
    benchmark: BenchmarkConfig = Field(..., description="基准配置")
    
    # 回测
    backtest: BacktestConfig = Field(..., description="回测配置")
    
    # 因子
    factor: FactorConfig = Field(default_factory=FactorConfig, description="因子配置")
    
    # 轮动
    rotation: RotationConfig = Field(default_factory=RotationConfig, description="轮动配置")
    
    # 调仓
    rebalance: RebalanceConfig = Field(default_factory=RebalanceConfig, description="调仓配置")
    
    # 溢价控制
    premium_control: PremiumControlConfig = Field(default_factory=PremiumControlConfig, description="溢价控制")
    
    # 数据
    data: DataConfig = Field(..., description="数据配置")


# ============================================================
# 通用策略配置 Schema（V2 架构）
# ============================================================

class StrategyConfig(BaseModel):
    """
    通用策略配置（支持所有策略类型）
    
    使用示例:
        from framework_v2.config import load_config
        config = load_config('rotation.yaml')
    """
    metadata: MetadataConfig = Field(default_factory=MetadataConfig, description="元数据")
    
    # 资产池
    asset_pools: AssetPool = Field(..., description="资产池配置")
    
    # 基准
    benchmark: BenchmarkConfig = Field(..., description="基准配置")
    
    # 回测
    backtest: BacktestConfig = Field(..., description="回测配置")
    
    # 因子
    factor: FactorConfig = Field(default_factory=FactorConfig, description="因子配置")
    
    # 轮动（可选）
    rotation: Optional[RotationConfig] = Field(None, description="轮动配置")
    
    # 调仓
    rebalance: RebalanceConfig = Field(default_factory=RebalanceConfig, description="调仓配置")
    
    # 溢价控制
    premium_control: PremiumControlConfig = Field(default_factory=PremiumControlConfig, description="溢价控制")
    
    # 数据
    data: DataConfig = Field(..., description="数据配置")