import enum
from datetime import datetime
from decimal import Decimal
from sqlalchemy import (
    Column,
    String,
    BigInteger,
    Integer,
    Numeric,
    DateTime,
    Enum,
    Index,
    JSON,
    ForeignKey,
    Boolean,
    Text,
)
from sqlalchemy.orm import declarative_base

Base = declarative_base()

class LedgerEntryType(str, enum.Enum):
    """复式记账操作类型"""
    DEPOSIT = "DEPOSIT"                         # 链上充值
    WITHDRAW = "WITHDRAW"                       # 提现
    TRADE_BUY = "TRADE_BUY"                     # 现货/曲线买入扣保证金
    TRADE_SELL = "TRADE_SELL"                   # 现货/曲线卖出增保证金
    FEE_PROTOCOL = "FEE_PROTOCOL"               # 协议手续费扣除
    FEE_CREATOR_REBATE = "FEE_CREATOR_REBATE"   # 建盘者返佣
    ORDER_FREEZE = "ORDER_FREEZE"               # 挂单冻结
    ORDER_UNFREEZE = "ORDER_UNFREEZE"           # 撤单解冻
    SETTLEMENT_PAYOUT = "SETTLEMENT_PAYOUT"     # 最终获胜兑付

class MarketStatus(str, enum.Enum):
    ACTIVE = "ACTIVE"
    RESOLVED = "RESOLVED"
    FINALISED = "FINALISED"
    PAUSED = "PAUSED"

class UserModel(Base):
    """用户基础表"""
    __tablename__ = "users"

    address = Column(String(42), primary_key=True, index=True) # Checksum EVM Address
    created_at = Column(DateTime, default=datetime.utcnow, nullable=False)
    last_login_at = Column(DateTime, default=datetime.utcnow, nullable=False)
    is_active = Column(Boolean, default=True, nullable=False)

class AccountBalanceModel(Base):
    """账户资金总览表 (由 Ledger 聚合维护)"""
    __tablename__ = "account_balances"

    address = Column(String(42), primary_key=True, index=True)
    collateral_symbol = Column(String(16), primary_key=True, default="WUSD")
    available_balance = Column(Numeric(precision=36, scale=18), default=Decimal("0"), nullable=False)
    frozen_balance = Column(Numeric(precision=36, scale=18), default=Decimal("0"), nullable=False)
    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow, nullable=False)

class LedgerEntryModel(Base):
    """
    不可变复式记账明细表 (Immutable Ledger)
    资金流转与状态变更的唯一法定事实源
    """
    __tablename__ = "ledger_entries"

    id = Column(BigInteger().with_variant(Integer, "sqlite"), primary_key=True, autoincrement=True)
    tx_hash = Column(String(66), nullable=True, index=True)
    chain_id = Column(BigInteger, default=46630, nullable=False)
    user_address = Column(String(42), nullable=False, index=True)
    entry_type = Column(Enum(LedgerEntryType), nullable=False, index=True)
    amount = Column(Numeric(precision=36, scale=18), nullable=False) # 变动金额 (+ / -)
    balance_after = Column(Numeric(precision=36, scale=18), nullable=False) # 变动后可用余额
    frozen_after = Column(Numeric(precision=36, scale=18), nullable=False) # 变动后冻结金额
    related_market = Column(String(42), nullable=True, index=True)
    related_order_id = Column(String(64), nullable=True, index=True)
    extra_metadata = Column(JSON, default=dict)
    created_at = Column(DateTime, default=datetime.utcnow, nullable=False, index=True)

    __table_args__ = (
        Index("idx_ledger_user_created", "user_address", "created_at"),
    )

class MarketModel(Base):
    """预测市场主表"""
    __tablename__ = "markets"

    market_address = Column(String(42), primary_key=True)
    question_id = Column(String(66), unique=True, nullable=False, index=True)
    title = Column(String(512), nullable=False)
    description = Column(Text, nullable=True)
    category = Column(String(64), default="Crypto", nullable=False, index=True)
    tier = Column(BigInteger, default=1, nullable=False)
    creator = Column(String(42), nullable=False, index=True)
    curve_address = Column(String(42), nullable=False)
    collateral_address = Column(String(42), nullable=False)
    fee_rate = Column(Numeric(precision=36, scale=18), default=Decimal("0.006"), nullable=False)
    resolution_time = Column(DateTime, nullable=False)
    outcomes = Column(JSON, nullable=False) # e.g. ["YES", "NO"]
    num_outcomes = Column(BigInteger, default=2, nullable=False)
    status = Column(Enum(MarketStatus), default=MarketStatus.ACTIVE, nullable=False, index=True)
    winning_outcome = Column(BigInteger, nullable=True)
    created_at_block = Column(BigInteger, nullable=False)
    created_at = Column(DateTime, default=datetime.utcnow, nullable=False)

class OrderModel(Base):
    """链下/链上委托订单明细"""
    __tablename__ = "orders"

    order_id = Column(String(64), primary_key=True)
    market_address = Column(String(42), ForeignKey("markets.market_address"), nullable=False, index=True)
    user_address = Column(String(42), nullable=False, index=True)
    side = Column(String(8), nullable=False) # "BUY" | "SELL"
    outcome_index = Column(BigInteger, nullable=False)
    amount = Column(Numeric(precision=36, scale=18), nullable=False) # WUSD 或 Token 数量
    price = Column(Numeric(precision=36, scale=18), nullable=True) # 限价 (若为市价则为空)
    status = Column(String(16), default="FILLED", nullable=False) # PENDING, FILLED, CANCELLED
    filled_amount = Column(Numeric(precision=36, scale=18), default=Decimal("0"), nullable=False)
    fee = Column(Numeric(precision=36, scale=18), default=Decimal("0"), nullable=False)
    tx_hash = Column(String(66), nullable=True)
    created_at = Column(DateTime, default=datetime.utcnow, nullable=False)