"""
Dashboard visualization components for Wildberries Analytics
Creates interactive charts and visualizations using Plotly
"""

import plotly.graph_objects as go
import plotly.express as px
from plotly.subplots import make_subplots
import pandas as pd
import numpy as np
from datetime import datetime, timedelta
from typing import Dict, List, Any, Optional
import logging
from wildberries_client import validate_wb_data, aggregate_wb_data

logger = logging.getLogger(__name__)

def create_sales_dashboard(sales_data: pd.DataFrame, period: str = "week", daily_revenue_data: pd.DataFrame = None) -> go.Figure:
    """
    Create comprehensive sales dashboard with multiple visualizations
    
    Args:
        sales_data: DataFrame with sales data
        period: Analysis period ("week" or "month")
        daily_revenue_data: Pre-calculated daily revenue data (optional)
        
    Returns:
        Plotly figure with sales dashboard
    """
    if sales_data.empty:
        return create_empty_chart("No sales data available")
    
    # Create subplot layout with better spacing
    fig = make_subplots(
        rows=3, cols=1,
        subplot_titles=[
            "📈 Daily Revenue Trend",
            "🏆 Top Products by Revenue",
            "📊 Sales by Category"
        ],
        specs=[[{"secondary_y": True}],
               [{"type": "bar"}],
               [{"type": "pie"}]],
        vertical_spacing=0.15,
        row_heights=[0.4, 0.35, 0.25]
    )
    
    try:
        # 1. Daily Revenue Trend (Top Left) - Use pre-calculated data if available
        if daily_revenue_data is not None and not daily_revenue_data.empty:
            # Use the pre-calculated daily revenue data to ensure consistency
            daily_revenue = daily_revenue_data.copy()
        elif 'sale_date' in sales_data.columns and 'total_price' in sales_data.columns:
            # Fallback to calculating if not provided
            daily_revenue = sales_data.groupby(sales_data['sale_date'].dt.date).agg({
                'total_price': 'sum',
                'quantity': 'sum'
            }).reset_index()
        else:
            daily_revenue = pd.DataFrame()
        
        if not daily_revenue.empty:
            # Revenue line
            fig.add_trace(
                go.Scatter(
                    x=daily_revenue['sale_date'],
                    y=daily_revenue['total_price'],
                    mode='lines+markers',
                    name='Revenue (₽)',
                    line=dict(color='#2E86AB', width=3),
                    marker=dict(size=8),
                    hovertemplate='<b>%{x}</b><br>Revenue: ₽%{y:,.0f}<extra></extra>'
                ),
                row=1, col=1
            )
            
            # Quantity bars on secondary y-axis
            fig.add_trace(
                go.Bar(
                    x=daily_revenue['sale_date'],
                    y=daily_revenue['quantity'],
                    name='Quantity',
                    marker_color='rgba(46, 134, 171, 0.3)',
                    yaxis='y2',
                    hovertemplate='<b>%{x}</b><br>Quantity: %{y}<extra></extra>'
                ),
                row=1, col=1, secondary_y=True
            )
        
        # 2. Top Products by Revenue (Second Row)
        if 'product_name' in sales_data.columns and 'total_price' in sales_data.columns:
            top_products = sales_data.groupby('product_name')['total_price'].sum().nlargest(8).reset_index()
            
            fig.add_trace(
                go.Bar(
                    x=top_products['total_price'],
                    y=top_products['product_name'],
                    orientation='h',
                    name='Top Products',
                    marker_color='#A23B72',
                    hovertemplate='<b>%{y}</b><br>Revenue: ₽%{x:,.0f}<extra></extra>'
                ),
                row=2, col=1
            )
        
        # 3. Sales by Category (Third Row)
        if 'category' in sales_data.columns and 'total_price' in sales_data.columns:
            category_sales = sales_data.groupby('category')['total_price'].sum().reset_index()
            
            fig.add_trace(
                go.Pie(
                    labels=category_sales['category'],
                    values=category_sales['total_price'],
                    name='Categories',
                    hovertemplate='<b>%{label}</b><br>Revenue: ₽%{value:,.0f}<br>Percent: %{percent}<extra></extra>',
                    marker_colors=px.colors.qualitative.Set3
                ),
                row=3, col=1
            )
    
    except Exception as e:
        logger.error(f"Error creating sales dashboard: {str(e)}")
        return create_empty_chart(f"Error creating dashboard: {str(e)}")
    
    # Update layout
    fig.update_layout(
        title=f"📊 Sales Analytics Dashboard - Last {period.title()}",
        title_x=0.5,
        showlegend=False,
        height=1100,
        font=dict(size=12),
        template="plotly_white",
        margin=dict(t=120, b=80, l=80, r=80)
    )
    
    # Update axes labels
    fig.update_xaxes(title_text="Date", row=1, col=1)
    fig.update_yaxes(title_text="Revenue (₽)", row=1, col=1)
    fig.update_yaxes(title_text="Quantity", secondary_y=True, row=1, col=1)
    
    fig.update_xaxes(title_text="Revenue (₽)", row=2, col=1)
    fig.update_yaxes(title_text="Products", row=2, col=1)
    
    return fig

def create_inventory_dashboard(forecast_data: pd.DataFrame) -> go.Figure:
    """
    Create inventory risk analysis dashboard
    
    Args:
        forecast_data: DataFrame with forecast results
        
    Returns:
        Plotly figure with inventory dashboard
    """
    if forecast_data.empty:
        return create_empty_chart("No inventory data available")
    
    # Create subplot layout
    fig = make_subplots(
        rows=3, cols=1,
        subplot_titles=[
            "🚨 Risk Level Distribution",
            "⏰ Days Until Stockout",
            "📦 Current Stock Levels"
        ],
        specs=[[{"type": "pie"}],
               [{"type": "bar"}],
               [{"type": "bar"}]],
        vertical_spacing=0.15,
        row_heights=[0.35, 0.35, 0.30]
    )
    
    try:
        # 1. Risk Level Distribution (Top Left)
        if 'risk_level' in forecast_data.columns:
            risk_counts = forecast_data['risk_level'].value_counts()
            colors = {
                '🔴 Critical': '#FF4444',
                '🟡 Warning': '#FFAA00', 
                '🟢 Safe': '#44AA44',
                '❌ Error': '#888888'
            }
            
            fig.add_trace(
                go.Pie(
                    labels=risk_counts.index,
                    values=risk_counts.values,
                    name='Risk Levels',
                    marker_colors=[colors.get(label, '#CCCCCC') for label in risk_counts.index],
                    hovertemplate='<b>%{label}</b><br>Count: %{value}<br>Percent: %{percent}<extra></extra>'
                ),
                row=1, col=1
            )
        
        # 2. Days Until Stockout (Top Right)
        if 'days_until_stockout' in forecast_data.columns and 'product_name' in forecast_data.columns:
            # Sort by days until stockout and take top 15 for readability
            sorted_data = forecast_data.nsmallest(15, 'days_until_stockout')
            
            # Color bars based on risk level
            bar_colors = []
            for days in sorted_data['days_until_stockout']:
                if days < 7:
                    bar_colors.append('#FF4444')
                elif days < 14:
                    bar_colors.append('#FFAA00')
                else:
                    bar_colors.append('#44AA44')
            
            fig.add_trace(
                go.Bar(
                    x=sorted_data['days_until_stockout'],
                    y=sorted_data['product_name'],
                    orientation='h',
                    name='Days Until Stockout',
                    marker_color=bar_colors,
                    hovertemplate='<b>%{y}</b><br>Days: %{x:.1f}<extra></extra>'
                ),
                row=2, col=1
            )
        
        # 3. Current Stock Levels (Third Row)
        if 'current_stock' in forecast_data.columns and 'product_name' in forecast_data.columns:
            # Take top 10 products by stock level for better visibility
            stock_data = forecast_data.nlargest(10, 'current_stock')
            
            fig.add_trace(
                go.Bar(
                    x=stock_data['product_name'],
                    y=stock_data['current_stock'],
                    name='Current Stock',
                    marker_color='#2E86AB',
                    hovertemplate='<b>%{x}</b><br>Stock: %{y}<extra></extra>'
                ),
                row=3, col=1
            )

    
    except Exception as e:
        logger.error(f"Error creating inventory dashboard: {str(e)}")
        return create_empty_chart(f"Error creating dashboard: {str(e)}")
    
    # Update layout
    fig.update_layout(
        title="📦 Inventory Risk Analysis Dashboard",
        title_x=0.5,
        showlegend=False,
        height=1100,
        font=dict(size=12),
        template="plotly_white",
        margin=dict(t=120, b=80, l=80, r=80)
    )
    
    # Update axes
    fig.update_xaxes(title_text="Days", row=2, col=1)
    fig.update_yaxes(title_text="Products", row=2, col=1)
    
    fig.update_xaxes(title_text="Products", row=3, col=1, tickangle=45)
    fig.update_yaxes(title_text="Stock Quantity", row=3, col=1)
    
    return fig

def create_trend_chart(data: pd.DataFrame, 
                      date_col: str = 'sale_date',
                      value_col: str = 'total_price',
                      title: str = "Trend Analysis") -> go.Figure:
    """
    Create a trend analysis chart
    
    Args:
        data: DataFrame with time series data
        date_col: Name of date column
        value_col: Name of value column
        title: Chart title
        
    Returns:
        Plotly figure with trend chart
    """
    if data.empty:
        return create_empty_chart("No data available for trend analysis")
    
    try:
        # Group by date
        if date_col in data.columns and value_col in data.columns:
            daily_data = data.groupby(data[date_col].dt.date)[value_col].sum().reset_index()
            
            fig = go.Figure()
            
            # Add main trend line
            fig.add_trace(
                go.Scatter(
                    x=daily_data[date_col],
                    y=daily_data[value_col],
                    mode='lines+markers',
                    name='Daily Values',
                    line=dict(color='#2E86AB', width=3),
                    marker=dict(size=8),
                    hovertemplate='<b>%{x}</b><br>Value: %{y:,.0f}<extra></extra>'
                )
            )
            
            # Add moving average if enough data points
            if len(daily_data) >= 7:
                daily_data['ma7'] = daily_data[value_col].rolling(window=7, center=True).mean()
                
                fig.add_trace(
                    go.Scatter(
                        x=daily_data[date_col],
                        y=daily_data['ma7'],
                        mode='lines',
                        name='7-day Moving Average',
                        line=dict(color='#A23B72', width=2, dash='dash'),
                        hovertemplate='<b>%{x}</b><br>7-day MA: %{y:,.0f}<extra></extra>'
                    )
                )
            
            fig.update_layout(
                title=title,
                title_x=0.5,
                xaxis_title="Date",
                yaxis_title="Value",
                template="plotly_white",
                height=400
            )
            
            return fig
        else:
            return create_empty_chart(f"Required columns not found: {date_col}, {value_col}")
            
    except Exception as e:
        logger.error(f"Error creating trend chart: {str(e)}")
        return create_empty_chart(f"Error creating chart: {str(e)}")

def create_comparison_chart(data: pd.DataFrame,
                          category_col: str = 'category',
                          value_col: str = 'total_price',
                          title: str = "Category Comparison") -> go.Figure:
    """
    Create a comparison chart for categories
    
    Args:
        data: DataFrame with categorical data
        category_col: Name of category column
        value_col: Name of value column
        title: Chart title
        
    Returns:
        Plotly figure with comparison chart
    """
    if data.empty:
        return create_empty_chart("No data available for comparison")
    
    try:
        if category_col in data.columns and value_col in data.columns:
            category_data = data.groupby(category_col)[value_col].sum().sort_values(ascending=True)
            
            fig = go.Figure()
            
            fig.add_trace(
                go.Bar(
                    x=category_data.values,
                    y=category_data.index,
                    orientation='h',
                    marker_color=px.colors.qualitative.Set3,
                    hovertemplate='<b>%{y}</b><br>Value: %{x:,.0f}<extra></extra>'
                )
            )
            
            fig.update_layout(
                title=title,
                title_x=0.5,
                xaxis_title="Value",
                yaxis_title="Category",
                template="plotly_white",
                height=400
            )
            
            return fig
        else:
            return create_empty_chart(f"Required columns not found: {category_col}, {value_col}")
            
    except Exception as e:
        logger.error(f"Error creating comparison chart: {str(e)}")
        return create_empty_chart(f"Error creating chart: {str(e)}")

def create_empty_chart(message: str = "No data available") -> go.Figure:
    """
    Create an empty chart with a message
    
    Args:
        message: Message to display
        
    Returns:
        Plotly figure with message
    """
    fig = go.Figure()
    
    fig.add_annotation(
        x=0.5,
        y=0.5,
        xref="paper",
        yref="paper",
        text=message,
        showarrow=False,
        font=dict(size=16, color="gray"),
        xanchor="center",
        yanchor="middle"
    )
    
    fig.update_layout(
        template="plotly_white",
        height=400,
        xaxis=dict(showgrid=False, showticklabels=False, zeroline=False),
        yaxis=dict(showgrid=False, showticklabels=False, zeroline=False)
    )
    
    return fig

def create_kpi_cards(data: pd.DataFrame) -> Dict[str, Any]:
    """
    Calculate KPIs for dashboard cards
    
    Args:
        data: DataFrame with sales/inventory data
        
    Returns:
        Dictionary with KPI values
    """
    if data.empty:
        return {
            "total_revenue": 0,
            "total_orders": 0,
            "avg_order_value": 0,
            "top_product": "N/A"
        }
    
    kpis = {}
    
    try:
        # Revenue metrics
        if 'total_price' in data.columns:
            kpis['total_revenue'] = data['total_price'].sum()
            kpis['avg_order_value'] = data['total_price'].mean()
        else:
            kpis['total_revenue'] = 0
            kpis['avg_order_value'] = 0
        
        # Order count (net orders: sales minus returns)
        if 'is_return' in data.columns:
            sales_count = (~data['is_return']).sum()
            returns_count = data['is_return'].sum()
            kpis['total_orders'] = sales_count - returns_count
            kpis['sales_count'] = sales_count
            kpis['returns_count'] = returns_count
        else:
            kpis['total_orders'] = len(data)
        
        # Top product
        if 'product_name' in data.columns and 'total_price' in data.columns:
            top_product = data.groupby('product_name')['total_price'].sum().idxmax()
            kpis['top_product'] = top_product
        else:
            kpis['top_product'] = "N/A"
        
        # Growth calculations (if date column available)
        if 'sale_date' in data.columns:
            # Calculate week-over-week growth
            current_week = data[data['sale_date'] >= (datetime.now() - timedelta(days=7))]
            previous_week = data[
                (data['sale_date'] >= (datetime.now() - timedelta(days=14))) &
                (data['sale_date'] < (datetime.now() - timedelta(days=7)))
            ]
            
            current_revenue = current_week['total_price'].sum() if 'total_price' in data.columns else 0
            previous_revenue = previous_week['total_price'].sum() if 'total_price' in data.columns else 0
            
            if previous_revenue > 0:
                growth_rate = ((current_revenue - previous_revenue) / previous_revenue) * 100
                kpis['revenue_growth'] = round(growth_rate, 1)
            else:
                kpis['revenue_growth'] = 0
        
    except Exception as e:
        logger.error(f"Error calculating KPIs: {str(e)}")
        kpis = {
            "total_revenue": 0,
            "total_orders": 0, 
            "avg_order_value": 0,
            "top_product": "Error calculating",
            "revenue_growth": 0
        }
    
    return kpis

def format_metric(value: float, metric_type: str = "currency") -> str:
    """
    Format metrics for display
    
    Args:
        value: Numeric value to format
        metric_type: Type of metric ("currency", "number", "percent")
        
    Returns:
        Formatted string
    """
    if pd.isna(value) or value is None:
        return "N/A"
    
    try:
        if metric_type == "currency":
            return f"₽{value:,.0f}"
        elif metric_type == "percent":
            return f"{value:+.1f}%"
        elif metric_type == "number":
            return f"{value:,.0f}"
        else:
            return str(value)
    except:
        return "N/A"

def create_wb_kpi_cards(data: pd.DataFrame) -> Dict[str, Any]:
    """Enhanced KPIs specifically for Wildberries data"""
    kpis = create_kpi_cards(data)  # Use existing function
    
    try:
        # Add Wildberries-specific metrics
        if 'sales_commission' in data.columns:
            total_commission = data['sales_commission'].sum()
            kpis['total_commission'] = total_commission
            
            if 'total_price' in data.columns and data['total_price'].sum() > 0:
                commission_rate = (total_commission / data['total_price'].sum() * 100)
                kpis['avg_commission_rate'] = commission_rate
            else:
                kpis['avg_commission_rate'] = 0
        
        if 'amount_for_pay' in data.columns:
            kpis['total_payout'] = data['amount_for_pay'].sum()
            
            # Calculate net profit (amount_for_pay is what seller receives)
            if 'total_price' in data.columns:
                gross_revenue = data['total_price'].sum()
                net_revenue = data['amount_for_pay'].sum()
                kpis['platform_fees'] = gross_revenue - net_revenue
                kpis['net_margin_percent'] = (net_revenue / gross_revenue * 100) if gross_revenue > 0 else 0
        
        if 'office_name' in data.columns:
            office_sales = data.groupby('office_name')['total_price'].sum()
            if not office_sales.empty:
                kpis['top_office'] = office_sales.idxmax()
                kpis['top_office_revenue'] = office_sales.max()
        
        if 'delivery_cost' in data.columns:
            kpis['total_delivery_cost'] = data['delivery_cost'].sum()
        
        # Calculate sales velocity (average daily sales)
        if 'sale_date' in data.columns and not data.empty:
            date_range = (data['sale_date'].max() - data['sale_date'].min()).days
            if date_range > 0:
                kpis['daily_sales_velocity'] = len(data) / date_range
            else:
                kpis['daily_sales_velocity'] = len(data)
    
    except Exception as e:
        logger.error(f"Error calculating Wildberries KPIs: {str(e)}")
    
    return kpis

def create_commission_analysis_chart(sales_data: pd.DataFrame) -> go.Figure:
    """Create commission analysis visualization for Wildberries data"""
    if sales_data.empty or 'sales_commission' not in sales_data.columns:
        return create_empty_chart("No commission data available")
    
    fig = make_subplots(
        rows=2, cols=2,
        subplot_titles=[
            "Commission by Product",
            "Commission Rate Trend",
            "Revenue vs Commission",
            "Top Commission Products"
        ],
        specs=[[{"type": "bar"}, {"type": "scatter"}],
               [{"type": "scatter"}, {"type": "bar"}]],
        vertical_spacing=0.1,
        horizontal_spacing=0.1
    )
    
    try:
        # 1. Commission by Product (Top 10)
        if 'product_name' in sales_data.columns:
            product_commission = sales_data.groupby('product_name')['sales_commission'].sum().nlargest(10)
            
            fig.add_trace(
                go.Bar(
                    x=product_commission.index,
                    y=product_commission.values,
                    name='Commission',
                    marker_color='#FF6B6B',
                    hovertemplate='<b>%{x}</b><br>Commission: ₽%{y:,.0f}<extra></extra>'
                ),
                row=1, col=1
            )
        
        # 2. Daily commission trend
        if 'sale_date' in sales_data.columns:
            daily_commission = sales_data.groupby(sales_data['sale_date'].dt.date)['sales_commission'].sum()
            
            fig.add_trace(
                go.Scatter(
                    x=daily_commission.index,
                    y=daily_commission.values,
                    mode='lines+markers',
                    name='Daily Commission',
                    line=dict(color='#4ECDC4', width=2),
                    hovertemplate='<b>%{x}</b><br>Commission: ₽%{y:,.0f}<extra></extra>'
                ),
                row=1, col=2
            )
        
        # 3. Revenue vs Commission scatter
        if 'total_price' in sales_data.columns and 'product_name' in sales_data.columns:
            product_data = sales_data.groupby('product_name').agg({
                'total_price': 'sum',
                'sales_commission': 'sum'
            }).reset_index()
            
            fig.add_trace(
                go.Scatter(
                    x=product_data['total_price'],
                    y=product_data['sales_commission'],
                    mode='markers',
                    name='Revenue vs Commission',
                    marker=dict(
                        size=8,
                        color='#45B7D1',
                        opacity=0.7
                    ),
                    text=product_data['product_name'],
                    hovertemplate='<b>%{text}</b><br>Revenue: ₽%{x:,.0f}<br>Commission: ₽%{y:,.0f}<extra></extra>'
                ),
                row=2, col=1
            )
        
        # 4. Commission rate by product
        if 'product_name' in sales_data.columns and 'total_price' in sales_data.columns:
            product_stats = sales_data.groupby('product_name').agg({
                'total_price': 'sum',
                'sales_commission': 'sum'
            })
            product_stats['commission_rate'] = (product_stats['sales_commission'] / product_stats['total_price'] * 100)
            top_rates = product_stats['commission_rate'].nlargest(10)
            
            fig.add_trace(
                go.Bar(
                    x=top_rates.index,
                    y=top_rates.values,
                    name='Commission Rate (%)',
                    marker_color='#96CEB4',
                    hovertemplate='<b>%{x}</b><br>Commission Rate: %{y:.1f}%<extra></extra>'
                ),
                row=2, col=2
            )
    
    except Exception as e:
        logger.error(f"Error creating commission analysis: {str(e)}")
        return create_empty_chart(f"Error creating commission analysis: {str(e)}")
    
    # Update layout
    fig.update_layout(
        title="💰 Commission Analysis Dashboard",
        title_x=0.5,
        showlegend=False,
        height=800,
        font=dict(size=10),
        template="plotly_white"
    )
    
    # Update axes
    fig.update_xaxes(title_text="Products", row=1, col=1)
    fig.update_yaxes(title_text="Commission (₽)", row=1, col=1)
    
    fig.update_xaxes(title_text="Date", row=1, col=2)
    fig.update_yaxes(title_text="Commission (₽)", row=1, col=2)
    
    fig.update_xaxes(title_text="Revenue (₽)", row=2, col=1)
    fig.update_yaxes(title_text="Commission (₽)", row=2, col=1)
    
    fig.update_xaxes(title_text="Products", row=2, col=2)
    fig.update_yaxes(title_text="Commission Rate (%)", row=2, col=2)
    
    return fig

def validate_and_process_wb_data(weekly_data: pd.DataFrame, monthly_data: pd.DataFrame) -> Dict[str, Any]:
    """Validate and process Wildberries data with enhanced error handling"""
    
    # Run validation
    validation_results = validate_wb_data(weekly_data, monthly_data)
    
    # Process data for better performance if large datasets
    processed_data = {
        "weekly": weekly_data,
        "monthly": monthly_data,
        "validation": validation_results
    }
    
    # Aggregate data if datasets are large (>1000 records)
    if len(weekly_data) > 1000:
        processed_data["weekly_aggregated"] = aggregate_wb_data(weekly_data, 'daily')
        logger.info(f"Aggregated weekly data from {len(weekly_data)} to {len(processed_data['weekly_aggregated'])} records")
    
    if len(monthly_data) > 1000:
        processed_data["monthly_aggregated"] = aggregate_wb_data(monthly_data, 'daily')
        logger.info(f"Aggregated monthly data from {len(monthly_data)} to {len(processed_data['monthly_aggregated'])} records")
    
    return processed_data