import SwiftUI

// MARK: - Gradient Icon

struct GradientIcon: View {
    let icon: String
    let colors: [Color]
    var size: CGFloat = 36

    var body: some View {
        ZStack {
            Circle()
                .fill(
                    LinearGradient(
                        colors: colors.map { $0.opacity(0.2) },
                        startPoint: .topLeading,
                        endPoint: .bottomTrailing
                    )
                )
                .frame(width: size, height: size)

            Image(systemName: icon)
                .font(.system(size: size * 0.4))
                .foregroundStyle(
                    LinearGradient(
                        colors: colors,
                        startPoint: .topLeading,
                        endPoint: .bottomTrailing
                    )
                )
        }
    }
}

// MARK: - Base Metric Card

struct MetricCardView: View {
    let icon: String
    let title: String
    let value: String
    let subtitle: String
    let color: Color
    var gradientColors: [Color]? = nil
    var progress: Double? = nil
    var progressMax: Double = 1.0

    @State private var appeared = false

    var body: some View {
        VStack(alignment: .leading, spacing: 12) {
            HStack {
                GradientIcon(icon: icon, colors: gradientColors ?? [color, color.opacity(0.6)])
                Spacer()
            }

            Text(value)
                .font(.title2.bold())
                .foregroundColor(.white)

            Text(title)
                .font(.subheadline.weight(.medium))
                .foregroundColor(.white.opacity(0.7))

            if subtitle.isEmpty == false {
                Text(subtitle)
                    .font(.caption)
                    .foregroundColor(Color(hex: "8888aa"))
                    .lineLimit(2)
            }

            if let progress = progress {
                VStack(spacing: 4) {
                    GeometryReader { geo in
                        ZStack(alignment: .leading) {
                            RoundedRectangle(cornerRadius: 4)
                                .fill(Color.white.opacity(0.08))

                            RoundedRectangle(cornerRadius: 4)
                                .fill(
                                    LinearGradient(
                                        colors: gradientColors ?? [color, color.opacity(0.6)],
                                        startPoint: .leading,
                                        endPoint: .trailing
                                    )
                                )
                                .frame(width: geo.size.width * min(CGFloat(progress / progressMax), 1.0))
                        }
                    }
                    .frame(height: 6)

                    HStack {
                        Spacer()
                        Text("\(Int(progress / progressMax * 100))% от цели")
                            .font(.system(size: 10))
                            .foregroundColor(Color(hex: "8888aa"))
                    }
                }
            }
        }
        .padding(16)
        .background(
            RoundedRectangle(cornerRadius: 20)
                .fill(.ultraThinMaterial)
                .overlay(
                    RoundedRectangle(cornerRadius: 20)
                        .fill(Color(hex: "12122a").opacity(0.7))
                )
        )
        .shadow(color: .black.opacity(0.15), radius: 8, y: 4)
        .opacity(appeared ? 1 : 0)
        .offset(y: appeared ? 0 : 15)
        .onAppear {
            withAnimation(.easeOut(duration: 0.5).delay(0.1)) {
                appeared = true
            }
        }
    }
}

// MARK: - Sleep Card

struct SleepCard: View {
    let sleep: SleepData
    @State private var appeared = false

    var totalHours: Double { sleep.totalSleep ?? 0 }
    var deepMin: Int { Int((sleep.deep ?? 0) * 60) }
    var remHours: String { formatHours(sleep.rem ?? 0) }
    var coreHours: String { formatHours(sleep.core ?? 0) }

    var body: some View {
        VStack(alignment: .leading, spacing: 12) {
            HStack {
                GradientIcon(icon: "moon.fill", colors: [Color(hex: "7c3aed"), Color(hex: "a78bfa")])
                Spacer()
            }

            Text(String(format: "%.1f ч", totalHours))
                .font(.title2.bold())
                .foregroundColor(.white)

            Text("Сон")
                .font(.subheadline.weight(.medium))
                .foregroundColor(.white.opacity(0.7))

            VStack(alignment: .leading, spacing: 4) {
                HStack(spacing: 12) {
                    SleepPhase(label: "Deep", value: "\(deepMin)мин", color: Color(hex: "7c3aed"))
                    SleepPhase(label: "REM", value: remHours, color: Color(hex: "a78bfa"))
                    SleepPhase(label: "Core", value: coreHours, color: Color(hex: "c4b5fd"))
                }
                .font(.system(size: 10))
            }

            // Progress to 9h goal
            GeometryReader { geo in
                ZStack(alignment: .leading) {
                    RoundedRectangle(cornerRadius: 4)
                        .fill(Color.white.opacity(0.08))
                    RoundedRectangle(cornerRadius: 4)
                        .fill(
                            LinearGradient(
                                colors: [Color(hex: "7c3aed"), Color(hex: "a78bfa")],
                                startPoint: .leading,
                                endPoint: .trailing
                            )
                        )
                        .frame(width: geo.size.width * min(CGFloat(totalHours / 9.0), 1.0))
                }
            }
            .frame(height: 6)
        }
        .padding(16)
        .background(
            RoundedRectangle(cornerRadius: 20)
                .fill(.ultraThinMaterial)
                .overlay(
                    RoundedRectangle(cornerRadius: 20)
                        .fill(Color(hex: "12122a").opacity(0.7))
                )
        )
        .shadow(color: .black.opacity(0.15), radius: 8, y: 4)
        .opacity(appeared ? 1 : 0)
        .offset(y: appeared ? 0 : 15)
        .onAppear {
            withAnimation(.easeOut(duration: 0.5).delay(0.15)) {
                appeared = true
            }
        }
    }

    private func formatHours(_ h: Double) -> String {
        if h < 1 { return "\(Int(h * 60))мин" }
        return String(format: "%.0fч", h)
    }
}

struct SleepPhase: View {
    let label: String
    let value: String
    let color: Color

    var body: some View {
        VStack(alignment: .leading, spacing: 2) {
            Text(label)
                .foregroundColor(Color(hex: "8888aa"))
            Text(value)
                .foregroundColor(color)
                .fontWeight(.medium)
        }
    }
}

// MARK: - Steps Card

struct StepsCard: View {
    let steps: Int
    let goal: Int = 8000
    @State private var appeared = false

    var progress: Double { Double(steps) / Double(goal) }
    var percent: Int { Int(progress * 100) }

    var body: some View {
        VStack(alignment: .leading, spacing: 12) {
            HStack {
                GradientIcon(icon: "figure.walk", colors: [Color(hex: "ffa502"), Color(hex: "ff6348")])
                Spacer()
            }

            Text(formatSteps(steps))
                .font(.title2.bold())
                .foregroundColor(.white)

            Text("Шаги")
                .font(.subheadline.weight(.medium))
                .foregroundColor(.white.opacity(0.7))

            GeometryReader { geo in
                ZStack(alignment: .leading) {
                    RoundedRectangle(cornerRadius: 4)
                        .fill(Color.white.opacity(0.08))
                    RoundedRectangle(cornerRadius: 4)
                        .fill(
                            LinearGradient(
                                colors: [Color(hex: "ffa502"), Color(hex: "ff6348")],
                                startPoint: .leading,
                                endPoint: .trailing
                            )
                        )
                        .frame(width: geo.size.width * min(CGFloat(progress), 1.0))
                }
            }
            .frame(height: 6)

            Text("\(percent)% от цели")
                .font(.system(size: 10))
                .foregroundColor(Color(hex: "8888aa"))
        }
        .padding(16)
        .background(
            RoundedRectangle(cornerRadius: 20)
                .fill(.ultraThinMaterial)
                .overlay(
                    RoundedRectangle(cornerRadius: 20)
                        .fill(Color(hex: "12122a").opacity(0.7))
                )
        )
        .shadow(color: .black.opacity(0.15), radius: 8, y: 4)
        .opacity(appeared ? 1 : 0)
        .offset(y: appeared ? 0 : 15)
        .onAppear {
            withAnimation(.easeOut(duration: 0.5).delay(0.25)) {
                appeared = true
            }
        }
    }

    private func formatSteps(_ n: Int) -> String {
        let formatter = NumberFormatter()
        formatter.numberStyle = .decimal
        formatter.groupingSeparator = " "
        return formatter.string(from: NSNumber(value: n)) ?? "\(n)"
    }
}

// MARK: - Insights Card

struct InsightsCard: View {
    let readiness: ReadinessResponse?
    let latest: LatestHealthResponse?
    @State private var appeared = false

    var insights: [(icon: String, text: String, color: Color)] {
        var result: [(String, String, Color)] = []

        if let r = readiness {
            if r.score >= 80 {
                result.append(("bolt.fill", "Отличный день для тренировки!", Color(hex: "00d4aa")))
            } else if r.score < 60 {
                result.append(("bed.double.fill", "Сегодня лучше отдохнуть", Color(hex: "ff4757")))
            }
        }

        if let sleep = latest?.sleep?.totalSleep, sleep < 7 {
            result.append(("moon.zzz.fill", "Мало сна — постарайся лечь раньше", Color(hex: "7c3aed")))
        }

        if let hrv = latest?.hrv?.avg, hrv > 50 {
            result.append(("heart.fill", "HRV в норме — хороший знак", Color(hex: "00d4aa")))
        } else if let hrv = latest?.hrv?.avg, hrv > 0 {
            result.append(("exclamationmark.triangle.fill", "HRV ниже нормы — следи за стрессом", Color(hex: "ffa502")))
        }

        if let steps = latest?.steps?.total, steps > 0 && steps < 5000 {
            result.append(("figure.walk", "Мало шагов — прогуляйся!", Color(hex: "ffa502")))
        }

        if result.isEmpty {
            result.append(("sparkles", "Данные обновятся после синхронизации", Color(hex: "8888aa")))
        }

        return result
    }

    var body: some View {
        VStack(alignment: .leading, spacing: 14) {
            HStack {
                GradientIcon(icon: "lightbulb.fill", colors: [Color(hex: "ffa502"), Color(hex: "ff6348")])
                Text("Инсайты")
                    .font(.headline.weight(.semibold))
                    .foregroundColor(.white)
                Spacer()
            }

            ForEach(Array(insights.enumerated()), id: \.offset) { _, insight in
                HStack(spacing: 12) {
                    Image(systemName: insight.icon)
                        .font(.subheadline)
                        .foregroundColor(insight.color)
                        .frame(width: 24)

                    Text(insight.text)
                        .font(.subheadline)
                        .foregroundColor(.white.opacity(0.85))
                        .lineLimit(2)
                }
            }
        }
        .padding(20)
        .background(
            RoundedRectangle(cornerRadius: 20)
                .fill(.ultraThinMaterial)
                .overlay(
                    RoundedRectangle(cornerRadius: 20)
                        .fill(Color(hex: "12122a").opacity(0.7))
                )
        )
        .shadow(color: .black.opacity(0.2), radius: 10, y: 5)
        .padding(.horizontal)
        .opacity(appeared ? 1 : 0)
        .offset(y: appeared ? 0 : 20)
        .onAppear {
            withAnimation(.easeOut(duration: 0.5).delay(0.3)) {
                appeared = true
            }
        }
    }
}