from __future__ import annotations

from datetime import date
from decimal import Decimal, InvalidOperation

from PySide6.QtCore import QDate
from PySide6.QtWidgets import (
    QCheckBox,
    QComboBox,
    QDateEdit,
    QDialog,
    QDialogButtonBox,
    QDoubleSpinBox,
    QFormLayout,
    QHBoxLayout,
    QLabel,
    QLineEdit,
    QMessageBox,
    QPushButton,
    QSpinBox,
    QTextEdit,
    QVBoxLayout,
)

from grid_trading.domain.models import (
    Account,
    Instrument,
    StrategyTemplate,
    Trade,
    TradeGroup,
    TradeSide,
)
from grid_trading.services.trading_service import TradingService


class AccountDialog(QDialog):
    def __init__(self, account: Account, parent=None):
        super().__init__(parent)
        self.setWindowTitle("账户设置")
        self._account = account

        self.name_edit = QLineEdit(account.name)
        self.cash_edit = _money_spinbox(account.initial_cash)
        self.notes_edit = QTextEdit(account.notes)
        self.notes_edit.setFixedHeight(70)

        form = QFormLayout()
        form.addRow("账户名称", self.name_edit)
        form.addRow("初始资金", self.cash_edit)
        form.addRow("备注", self.notes_edit)

        buttons = QDialogButtonBox(QDialogButtonBox.StandardButton.Ok | QDialogButtonBox.StandardButton.Cancel)
        buttons.accepted.connect(self.accept)
        buttons.rejected.connect(self.reject)

        layout = QVBoxLayout(self)
        layout.addLayout(form)
        layout.addWidget(buttons)

    def to_account(self) -> Account:
        return Account(
            id=self._account.id,
            name=self.name_edit.text().strip(),
            initial_cash=Decimal(str(self.cash_edit.value())),
            notes=self.notes_edit.toPlainText().strip(),
        )


class InstrumentDialog(QDialog):
    def __init__(self, instrument: Instrument | None = None, parent=None):
        super().__init__(parent)
        self.setWindowTitle("标的设置")
        self._instrument = instrument

        self.code_edit = QLineEdit(instrument.code if instrument else "")
        self.name_edit = QLineEdit(instrument.name if instrument else "")
        self.market_edit = QComboBox()
        self.market_edit.addItems(["A", "ETF"])
        if instrument:
            self.market_edit.setCurrentText(instrument.market)
        self.lot_size_edit = QSpinBox()
        self.lot_size_edit.setRange(1, 1_000_000)
        self.lot_size_edit.setValue(instrument.lot_size if instrument else 100)
        self.manual_price_edit = QLineEdit(str(instrument.manual_price or "") if instrument else "")
        self.allow_odd_lot_edit = QCheckBox("允许非整手")
        self.allow_odd_lot_edit.setChecked(instrument.allow_odd_lot if instrument else False)

        form = QFormLayout()
        form.addRow("代码", self.code_edit)
        form.addRow("名称", self.name_edit)
        form.addRow("市场", self.market_edit)
        form.addRow("交易单位", self.lot_size_edit)
        form.addRow("手动价格", self.manual_price_edit)
        form.addRow("", self.allow_odd_lot_edit)

        buttons = QDialogButtonBox(QDialogButtonBox.StandardButton.Ok | QDialogButtonBox.StandardButton.Cancel)
        buttons.accepted.connect(self.accept)
        buttons.rejected.connect(self.reject)

        layout = QVBoxLayout(self)
        layout.addLayout(form)
        layout.addWidget(buttons)

    def to_instrument(self) -> Instrument:
        manual_price = _optional_decimal(self.manual_price_edit.text().strip(), "手动价格")
        return Instrument(
            id=self._instrument.id if self._instrument else None,
            code=self.code_edit.text().strip(),
            name=self.name_edit.text().strip(),
            market=self.market_edit.currentText(),
            lot_size=self.lot_size_edit.value(),
            manual_price=manual_price,
            allow_odd_lot=self.allow_odd_lot_edit.isChecked(),
            active=True,
        )


class StrategyTemplateDialog(QDialog):
    def __init__(self, template: StrategyTemplate, parent=None):
        super().__init__(parent)
        self.setWindowTitle("默认网格策略")
        self._template = template

        self.name_edit = QLineEdit(template.name)
        self.grid_spacing_edit = _percent_spinbox(template.grid_spacing_pct)
        self.amount_per_grid_edit = _money_spinbox(template.amount_per_grid)
        self.base_target_edit = _money_spinbox(template.base_target_amount)
        self.max_position_edit = _money_spinbox(template.max_position_amount)
        self.min_lot_edit = QSpinBox()
        self.min_lot_edit.setRange(1, 1_000_000)
        self.min_lot_edit.setValue(template.min_lot)

        form = QFormLayout()
        form.addRow("模板名称", self.name_edit)
        form.addRow("网格间距", self.grid_spacing_edit)
        form.addRow("每格金额", self.amount_per_grid_edit)
        form.addRow("底仓目标金额", self.base_target_edit)
        form.addRow("最大投入金额", self.max_position_edit)
        form.addRow("最小交易单位", self.min_lot_edit)

        buttons = QDialogButtonBox(QDialogButtonBox.StandardButton.Ok | QDialogButtonBox.StandardButton.Cancel)
        buttons.accepted.connect(self.accept)
        buttons.rejected.connect(self.reject)

        layout = QVBoxLayout(self)
        layout.addLayout(form)
        layout.addWidget(buttons)

    def to_template(self) -> StrategyTemplate:
        return StrategyTemplate(
            id=self._template.id,
            name=self.name_edit.text().strip(),
            grid_spacing_pct=Decimal(str(self.grid_spacing_edit.value())) / Decimal("100"),
            amount_per_grid=Decimal(str(self.amount_per_grid_edit.value())),
            base_target_amount=Decimal(str(self.base_target_edit.value())),
            max_position_amount=Decimal(str(self.max_position_edit.value())),
            min_lot=self.min_lot_edit.value(),
            is_default=True,
        )


class TradeDialog(QDialog):
    def __init__(
        self,
        service: TradingService,
        account_id: int,
        instruments: list[Instrument],
        trade: Trade | None = None,
        parent=None,
    ):
        super().__init__(parent)
        self.setWindowTitle("成交记录")
        self._service = service
        self._account_id = account_id
        self._instruments = instruments
        self._trade = trade

        self.instrument_edit = QComboBox()
        for instrument in instruments:
            self.instrument_edit.addItem(f"{instrument.code} {instrument.name}", instrument.id)
        if trade:
            index = self.instrument_edit.findData(trade.instrument_id)
            if index >= 0:
                self.instrument_edit.setCurrentIndex(index)

        self.date_edit = QDateEdit()
        self.date_edit.setCalendarPopup(True)
        trade_date = trade.trade_date if trade else date.today()
        self.date_edit.setDate(QDate(trade_date.year, trade_date.month, trade_date.day))

        self.side_edit = QComboBox()
        self.side_edit.addItem("买入", TradeSide.BUY.value)
        self.side_edit.addItem("卖出", TradeSide.SELL.value)
        if trade:
            self.side_edit.setCurrentIndex(self.side_edit.findData(trade.side.value))

        self.group_edit = QComboBox()
        self.group_edit.addItem("底仓", TradeGroup.BASE.value)
        self.group_edit.addItem("网格", TradeGroup.GRID.value)
        self.group_edit.addItem("其他", TradeGroup.OTHER.value)
        if trade:
            self.group_edit.setCurrentIndex(self.group_edit.findData(trade.trade_group.value))

        self.price_edit = _money_spinbox(trade.price if trade else Decimal("0"))
        self.quantity_edit = QSpinBox()
        self.quantity_edit.setRange(1, 100_000_000)
        self.quantity_edit.setSingleStep(100)
        self.quantity_edit.setValue(trade.quantity if trade else 100)
        self.commission_edit = _money_spinbox(trade.commission if trade else Decimal("0"))
        self.stamp_tax_edit = _money_spinbox(trade.stamp_tax if trade else Decimal("0"))
        self.transfer_fee_edit = _money_spinbox(trade.transfer_fee if trade else Decimal("0"))
        self.notes_edit = QLineEdit(trade.notes if trade else "")

        estimate_button = QPushButton("估算费用")
        estimate_button.clicked.connect(self._estimate_fees)
        fee_row = QHBoxLayout()
        fee_row.addWidget(QLabel("手续费"))
        fee_row.addWidget(self.commission_edit)
        fee_row.addWidget(QLabel("印花税"))
        fee_row.addWidget(self.stamp_tax_edit)
        fee_row.addWidget(QLabel("过户费"))
        fee_row.addWidget(self.transfer_fee_edit)
        fee_row.addWidget(estimate_button)

        form = QFormLayout()
        form.addRow("标的", self.instrument_edit)
        form.addRow("日期", self.date_edit)
        form.addRow("方向", self.side_edit)
        form.addRow("分组", self.group_edit)
        form.addRow("价格", self.price_edit)
        form.addRow("数量", self.quantity_edit)
        form.addRow(fee_row)
        form.addRow("备注", self.notes_edit)

        buttons = QDialogButtonBox(QDialogButtonBox.StandardButton.Ok | QDialogButtonBox.StandardButton.Cancel)
        buttons.accepted.connect(self.accept)
        buttons.rejected.connect(self.reject)

        layout = QVBoxLayout(self)
        layout.addLayout(form)
        layout.addWidget(buttons)

    def to_trade(self) -> Trade:
        selected_date = self.date_edit.date().toPython()
        return Trade(
            id=self._trade.id if self._trade else None,
            account_id=self._account_id,
            instrument_id=self.instrument_edit.currentData(),
            trade_date=selected_date,
            side=TradeSide(self.side_edit.currentData()),
            price=Decimal(str(self.price_edit.value())),
            quantity=self.quantity_edit.value(),
            commission=Decimal(str(self.commission_edit.value())),
            stamp_tax=Decimal(str(self.stamp_tax_edit.value())),
            transfer_fee=Decimal(str(self.transfer_fee_edit.value())),
            trade_group=TradeGroup(self.group_edit.currentData()),
            notes=self.notes_edit.text().strip(),
        )

    def accept(self) -> None:
        if self.instrument_edit.currentData() is None:
            QMessageBox.warning(self, "无法保存", "请先添加标的")
            return
        super().accept()

    def _estimate_fees(self) -> None:
        fees = self._service.estimate_trade_fees(
            TradeSide(self.side_edit.currentData()),
            Decimal(str(self.price_edit.value())),
            self.quantity_edit.value(),
        )
        self.commission_edit.setValue(float(fees.commission))
        self.stamp_tax_edit.setValue(float(fees.stamp_tax))
        self.transfer_fee_edit.setValue(float(fees.transfer_fee))


def _money_spinbox(value: Decimal) -> QDoubleSpinBox:
    spinbox = QDoubleSpinBox()
    spinbox.setRange(0, 1_000_000_000)
    spinbox.setDecimals(4)
    spinbox.setValue(float(value))
    return spinbox


def _percent_spinbox(value: Decimal) -> QDoubleSpinBox:
    spinbox = QDoubleSpinBox()
    spinbox.setRange(0.01, 100)
    spinbox.setDecimals(2)
    spinbox.setSuffix("%")
    spinbox.setValue(float(value * Decimal("100")))
    return spinbox


def _optional_decimal(raw: str, label: str) -> Decimal | None:
    if not raw:
        return None
    try:
        return Decimal(raw)
    except InvalidOperation as exc:
        raise ValueError(f"{label} 不是有效数字") from exc