"""
Analytics Tab - Portfolio Analytics Dashboard.

Displays performance metrics, allocation, risk metrics, and top holdings.
"""

import logging
from PyQt6.QtWidgets import (
    QWidget, QVBoxLayout, QHBoxLayout, QGroupBox,
    QLabel, QTableWidget, QTableWidgetItem, QHeaderView,
    QGridLayout
)
from PyQt6.QtCore import Qt
from PyQt6.QtGui import QColor

from src.utils.formatters import format_currency, format_percentage, color_for_pnl

logger = logging.getLogger(__name__)


class AnalyticsTab(QWidget):
    """Analytics dashboard tab."""

    def __init__(self, parent):
        """
        Initialize analytics tab.

        Args:
            parent: MainWindow instance
        """
        super().__init__()
        self.parent = parent
        self.init_ui()
        self.load_data()

    def init_ui(self):
        """Initialize user interface."""
        layout = QVBoxLayout(self)

        # Performance section
        perf_group = QGroupBox("📊 PERFORMANCE")
        perf_layout = QGridLayout(perf_group)

        self.lbl_invested = QLabel("€ 0.00")
        self.lbl_current = QLabel("€ 0.00")
        self.lbl_pnl = QLabel("+€ 0.00 (+0.0%)")
        self.lbl_dividends = QLabel("€ 0.00")

        perf_layout.addWidget(QLabel("Total Invested:"), 0, 0)
        perf_layout.addWidget(self.lbl_invested, 0, 1)

        perf_layout.addWidget(QLabel("Current Value:"), 1, 0)
        perf_layout.addWidget(self.lbl_current, 1, 1)

        perf_layout.addWidget(QLabel("Total P&L:"), 2, 0)
        perf_layout.addWidget(self.lbl_pnl, 2, 1)

        perf_layout.addWidget(QLabel("Dividends:"), 3, 0)
        perf_layout.addWidget(self.lbl_dividends, 3, 1)

        layout.addWidget(perf_group)

        # Allocation section
        alloc_group = QGroupBox("📈 ALLOCATION")
        alloc_layout = QHBoxLayout(alloc_group)

        # By Type
        type_layout = QVBoxLayout()
        type_layout.addWidget(QLabel("<b>By Type:</b>"))
        self.lbl_alloc_type = QLabel()
        type_layout.addWidget(self.lbl_alloc_type)
        type_layout.addStretch()
        alloc_layout.addLayout(type_layout)

        # By Geography
        geo_layout = QVBoxLayout()
        geo_layout.addWidget(QLabel("<b>By Geography:</b>"))
        self.lbl_alloc_geo = QLabel()
        geo_layout.addWidget(self.lbl_alloc_geo)
        geo_layout.addStretch()
        alloc_layout.addLayout(geo_layout)

        layout.addWidget(alloc_group)

        # Risk Metrics section
        risk_group = QGroupBox("⚠️ RISK METRICS")
        risk_layout = QVBoxLayout(risk_group)

        self.lbl_max_holding = QLabel()
        self.lbl_stock_conc = QLabel()
        self.lbl_etf_conc = QLabel()
        self.lbl_diversification = QLabel()

        risk_layout.addWidget(self.lbl_max_holding)
        risk_layout.addWidget(self.lbl_stock_conc)
        risk_layout.addWidget(self.lbl_etf_conc)
        risk_layout.addWidget(self.lbl_diversification)

        layout.addWidget(risk_group)

        # Top 5 Holdings section
        top_group = QGroupBox("📌 TOP 5 HOLDINGS")
        top_layout = QVBoxLayout(top_group)

        self.table_top = QTableWidget()
        self.table_top.setColumnCount(4)
        self.table_top.setHorizontalHeaderLabels([
            "Ticker", "Value €", "Weight %", "P&L %"
        ])
        self.table_top.setMaximumHeight(200)

        # Configure table
        self.table_top.setAlternatingRowColors(True)
        header = self.table_top.horizontalHeader()
        header.setSectionResizeMode(0, QHeaderView.ResizeMode.Stretch)
        header.setSectionResizeMode(1, QHeaderView.ResizeMode.ResizeToContents)
        header.setSectionResizeMode(2, QHeaderView.ResizeMode.ResizeToContents)
        header.setSectionResizeMode(3, QHeaderView.ResizeMode.ResizeToContents)

        top_layout.addWidget(self.table_top)

        layout.addWidget(top_group)

        layout.addStretch()

    def load_data(self):
        """Load and display analytics data."""
        logger.debug("Loading analytics data...")

        try:
            # Reload portfolio
            self.parent.portfolio.load_holdings()

            # Update all sections
            self.update_performance()
            self.update_allocation()
            self.update_risk_metrics()
            self.update_top_holdings()

            logger.info("Analytics data loaded successfully")

        except Exception as e:
            logger.error(f"Error loading analytics: {e}", exc_info=True)

    def update_performance(self):
        """Update performance section."""
        perf = self.parent.analytics.get_performance_summary()

        # Total Invested
        self.lbl_invested.setText(format_currency(perf['total_invested']))

        # Current Value
        self.lbl_current.setText(format_currency(perf['current_value']))

        # Total P&L
        pnl_amount = perf['total_pnl_amount']
        pnl_percent = perf['total_pnl_percent']
        pnl_text = f"{format_currency(pnl_amount)} ({format_percentage(pnl_percent)})"
        pnl_color = color_for_pnl(pnl_amount)
        self.lbl_pnl.setText(pnl_text)
        self.lbl_pnl.setStyleSheet(f"color: {pnl_color}; font-weight: bold;")

        # Dividends
        self.lbl_dividends.setText(format_currency(perf['total_dividends']))

    def update_allocation(self):
        """Update allocation section."""
        # By Type
        alloc_type = self.parent.analytics.get_allocation_by_type()
        type_text = ""
        for asset_type, weight in sorted(alloc_type.items(), key=lambda x: x[1], reverse=True):
            type_text += f"• {asset_type}: {weight:.1f}%\n"
        self.lbl_alloc_type.setText(type_text)

        # By Geography
        alloc_geo = self.parent.analytics.get_allocation_by_geography()
        geo_text = ""
        for geography, weight in sorted(alloc_geo.items(), key=lambda x: x[1], reverse=True):
            geo_text += f"• {geography}: {weight:.1f}%\n"
        self.lbl_alloc_geo.setText(geo_text)

    def update_risk_metrics(self):
        """Update risk metrics section."""
        risk = self.parent.analytics.get_risk_metrics()
        diversification = self.parent.analytics.get_diversification_score()

        # Max Single Holding
        max_ticker, max_weight = risk['max_single_holding']
        warning_level = risk['concentration_warning']

        max_text = f"Max Single Holding: {max_weight:.1f}% ({max_ticker})"

        if warning_level == 'danger':
            max_text += " ⚠️ >60%"
            max_color = "#dc3545"  # Red
        elif warning_level == 'warning':
            max_text += " ⚠️ >40%"
            max_color = "#ffc107"  # Yellow
        else:
            max_color = "#28a745"  # Green

        self.lbl_max_holding.setText(max_text)
        self.lbl_max_holding.setStyleSheet(f"color: {max_color}; font-weight: bold;")

        # Stock Concentration
        self.lbl_stock_conc.setText(f"Stock Concentration: {risk['stock_concentration']:.1f}%")

        # ETF Concentration
        self.lbl_etf_conc.setText(f"ETF Concentration: {risk['etf_concentration']:.1f}%")

        # Diversification Score
        div_text = (f"Diversification: {diversification['diversification_score']:.0f}/100 "
                   f"({diversification['assessment']}) - "
                   f"{diversification['effective_holdings']:.1f} effective holdings")
        self.lbl_diversification.setText(div_text)

    def update_top_holdings(self):
        """Update top 5 holdings table."""
        top_holdings = self.parent.analytics.get_top_holdings(n=5)

        self.table_top.setRowCount(len(top_holdings))

        for row, holding in enumerate(top_holdings):
            # Ticker
            self.table_top.setItem(row, 0, QTableWidgetItem(holding['ticker']))

            # Value
            value_item = QTableWidgetItem(format_currency(holding['current_value']))
            value_item.setTextAlignment(Qt.AlignmentFlag.AlignRight | Qt.AlignmentFlag.AlignVCenter)
            self.table_top.setItem(row, 1, value_item)

            # Weight %
            weight_item = QTableWidgetItem(f"{holding['weight_pct']:.1f}%")
            weight_item.setTextAlignment(Qt.AlignmentFlag.AlignRight | Qt.AlignmentFlag.AlignVCenter)
            self.table_top.setItem(row, 2, weight_item)

            # P&L %
            pnl_pct = holding['pnl_percent']
            pnl_item = QTableWidgetItem(format_percentage(pnl_pct))
            pnl_item.setTextAlignment(Qt.AlignmentFlag.AlignRight | Qt.AlignmentFlag.AlignVCenter)
            pnl_item.setForeground(QColor(color_for_pnl(pnl_pct)))
            self.table_top.setItem(row, 3, pnl_item)