import WidgetKit
import SwiftUI
import CoreData

// MARK: - Widget Entry

struct InvestmentWidgetEntry: TimelineEntry {
    let date: Date
    let totalValue: Decimal
    let dayChange: Decimal
    let dayChangePercentage: Double
    let topSources: [(name: String, value: Decimal, color: String)]
    let sparklineData: [Decimal]
}

// MARK: - Widget Provider

struct InvestmentWidgetProvider: TimelineProvider {
    func placeholder(in context: Context) -> InvestmentWidgetEntry {
        InvestmentWidgetEntry(
            date: Date(),
            totalValue: 50000,
            dayChange: 250,
            dayChangePercentage: 0.5,
            topSources: [
                ("Stocks", 30000, "#10B981"),
                ("Bonds", 15000, "#3B82F6"),
                ("Real Estate", 5000, "#F59E0B")
            ],
            sparklineData: [45000, 46000, 47000, 48000, 49000, 50000]
        )
    }

    func getSnapshot(in context: Context, completion: @escaping (InvestmentWidgetEntry) -> Void) {
        let entry = fetchData()
        completion(entry)
    }

    func getTimeline(in context: Context, completion: @escaping (Timeline<InvestmentWidgetEntry>) -> Void) {
        let entry = fetchData()

        // Refresh every hour
        let nextUpdate = Calendar.current.date(byAdding: .hour, value: 1, to: Date()) ?? Date()
        let timeline = Timeline(entries: [entry], policy: .after(nextUpdate))

        completion(timeline)
    }

    private func fetchData() -> InvestmentWidgetEntry {
        let container = CoreDataStack.createWidgetContainer()
        let context = container.viewContext

        // Fetch sources
        let sourceRequest: NSFetchRequest<InvestmentSource> = InvestmentSource.fetchRequest()
        let sources = (try? context.fetch(sourceRequest)) ?? []

        // Calculate total value
        let totalValue = sources.reduce(Decimal.zero) { $0 + $1.latestValue }

        // Get top sources
        let topSources = sources
            .sorted { $0.latestValue > $1.latestValue }
            .prefix(3)
            .map { (name: $0.name, value: $0.latestValue, color: $0.category?.colorHex ?? "#3B82F6") }

        // Calculate day change (simplified - would need proper historical data)
        let dayChange: Decimal = 0
        let dayChangePercentage: Double = 0

        // Get sparkline data (last 6 data points)
        let sparklineData: [Decimal] = []

        return InvestmentWidgetEntry(
            date: Date(),
            totalValue: totalValue,
            dayChange: dayChange,
            dayChangePercentage: dayChangePercentage,
            topSources: Array(topSources),
            sparklineData: sparklineData
        )
    }
}

// MARK: - Small Widget View

struct SmallWidgetView: View {
    let entry: InvestmentWidgetEntry

    var body: some View {
        VStack(alignment: .leading, spacing: 8) {
            Text("Portfolio")
                .font(.caption)
                .foregroundColor(.secondary)

            Text(entry.totalValue.compactCurrencyString)
                .font(.title2.weight(.bold))
                .minimumScaleFactor(0.7)
                .lineLimit(1)

            Spacer()

            HStack(spacing: 4) {
                Image(systemName: entry.dayChange >= 0 ? "arrow.up.right" : "arrow.down.right")
                    .font(.caption2)

                Text(String(format: "%.1f%%", entry.dayChangePercentage))
                    .font(.caption.weight(.medium))
            }
            .foregroundColor(entry.dayChange >= 0 ? .green : .red)
        }
        .padding()
        .containerBackground(.background, for: .widget)
    }
}

// MARK: - Medium Widget View

struct MediumWidgetView: View {
    let entry: InvestmentWidgetEntry

    var body: some View {
        HStack(spacing: 16) {
            // Left side - Total value
            VStack(alignment: .leading, spacing: 8) {
                Text("Portfolio")
                    .font(.caption)
                    .foregroundColor(.secondary)

                Text(entry.totalValue.compactCurrencyString)
                    .font(.title.weight(.bold))
                    .minimumScaleFactor(0.7)
                    .lineLimit(1)

                HStack(spacing: 4) {
                    Image(systemName: entry.dayChange >= 0 ? "arrow.up.right" : "arrow.down.right")
                        .font(.caption2)

                    Text(entry.dayChange.compactCurrencyString)
                        .font(.caption.weight(.medium))

                    Text("(\(String(format: "%.1f%%", entry.dayChangePercentage)))")
                        .font(.caption)
                        .foregroundColor(.secondary)
                }
                .foregroundColor(entry.dayChange >= 0 ? .green : .red)
            }

            Spacer()

            // Right side - Top sources
            VStack(alignment: .trailing, spacing: 6) {
                ForEach(entry.topSources, id: \.name) { source in
                    HStack(spacing: 6) {
                        Text(source.name)
                            .font(.caption)
                            .foregroundColor(.secondary)
                            .lineLimit(1)

                        Text(source.value.shortCurrencyString)
                            .font(.caption.weight(.medium))
                    }
                }
            }
        }
        .padding()
        .containerBackground(.background, for: .widget)
    }
}

// MARK: - Accessory Circular View (Lock Screen)

struct AccessoryCircularView: View {
    let entry: InvestmentWidgetEntry

    var body: some View {
        ZStack {
            AccessoryWidgetBackground()

            VStack(spacing: 2) {
                Image(systemName: entry.dayChange >= 0 ? "arrow.up.right" : "arrow.down.right")
                    .font(.caption)

                Text(String(format: "%.1f%%", entry.dayChangePercentage))
                    .font(.caption2.weight(.semibold))
            }
        }
        .containerBackground(.background, for: .widget)
    }
}

// MARK: - Accessory Rectangular View (Lock Screen)

struct AccessoryRectangularView: View {
    let entry: InvestmentWidgetEntry

    var body: some View {
        VStack(alignment: .leading, spacing: 2) {
            Text("Portfolio")
                .font(.caption2)
                .foregroundColor(.secondary)

            Text(entry.totalValue.compactCurrencyString)
                .font(.headline)

            HStack(spacing: 4) {
                Image(systemName: entry.dayChange >= 0 ? "arrow.up.right" : "arrow.down.right")
                    .font(.caption2)

                Text(String(format: "%.1f%%", entry.dayChangePercentage))
                    .font(.caption2)
            }
            .foregroundColor(entry.dayChange >= 0 ? .green : .red)
        }
        .containerBackground(.background, for: .widget)
    }
}

// MARK: - Widget Configuration

struct InvestmentWidget: Widget {
    let kind: String = "InvestmentWidget"

    var body: some WidgetConfiguration {
        StaticConfiguration(kind: kind, provider: InvestmentWidgetProvider()) { entry in
            InvestmentWidgetEntryView(entry: entry)
        }
        .configurationDisplayName("Portfolio Value")
        .description("View your total investment portfolio value.")
        .supportedFamilies([
            .systemSmall,
            .systemMedium,
            .accessoryCircular,
            .accessoryRectangular
        ])
    }
}

// MARK: - Widget Entry View

struct InvestmentWidgetEntryView: View {
    @Environment(\.widgetFamily) var family
    let entry: InvestmentWidgetEntry

    var body: some View {
        switch family {
        case .systemSmall:
            SmallWidgetView(entry: entry)
        case .systemMedium:
            MediumWidgetView(entry: entry)
        case .accessoryCircular:
            AccessoryCircularView(entry: entry)
        case .accessoryRectangular:
            AccessoryRectangularView(entry: entry)
        default:
            SmallWidgetView(entry: entry)
        }
    }
}

// MARK: - Widget Bundle

@main
struct InvestmentTrackerWidgetBundle: WidgetBundle {
    var body: some Widget {
        InvestmentWidget()
    }
}

// MARK: - Previews

#Preview("Small", as: .systemSmall) {
    InvestmentWidget()
} timeline: {
    InvestmentWidgetEntry(
        date: Date(),
        totalValue: 50000,
        dayChange: 250,
        dayChangePercentage: 0.5,
        topSources: [],
        sparklineData: []
    )
}

#Preview("Medium", as: .systemMedium) {
    InvestmentWidget()
} timeline: {
    InvestmentWidgetEntry(
        date: Date(),
        totalValue: 50000,
        dayChange: 250,
        dayChangePercentage: 0.5,
        topSources: [
            ("Stocks", 30000, "#10B981"),
            ("Bonds", 15000, "#3B82F6"),
            ("Real Estate", 5000, "#F59E0B")
        ],
        sparklineData: []
    )
}