import Foundation
import SwiftUI

extension PizzaProductDetailSheet {
    var stepSizes: some View {
        let sizeItems = sizes
        return VStack(alignment: .leading, spacing: 10) {
            Text("1. Tamanho")
                .font(AppTypography.heading3)
                .foregroundStyle(AppColors.textPrimary)

            ForEach(Array(sizeItems.indices), id: \.self) { index in
                sizeRow(sizeItems[index])
            }
        }
        .padding(12)
        .background(AppColors.surface)
        .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))
    }

    var stepDoughs: some View {
        VStack(alignment: .leading, spacing: 10) {
            Text("2. Massa")
                .font(AppTypography.heading3)
                .foregroundStyle(AppColors.textPrimary)

            if doughs.count <= 1 {
                Text(doughs.first?.name ?? "Massa tradicional")
                    .font(AppTypography.body)
                    .foregroundStyle(AppColors.textPrimary)
            } else {
                ForEach(doughs) { dough in
                    radioRow(
                        title: dough.name ?? "Massa",
                        subtitle: nil,
                        isSelected: selectedDoughId == dough.id
                    ) {
                        selectedDoughId = dough.id
                    }
                }
            }
        }
        .padding(12)
        .background(AppColors.surface)
        .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))
    }

    var stepCrusts: some View {
        VStack(alignment: .leading, spacing: 10) {
            Text("3. Borda")
                .font(AppTypography.heading3)
                .foregroundStyle(AppColors.textPrimary)

            if crusts.count <= 1 {
                Text(crustDescription(crusts.first))
                    .font(AppTypography.body)
                    .foregroundStyle(AppColors.textPrimary)
            } else {
                ForEach(crusts) { crust in
                    radioRow(
                        title: crust.name ?? "Borda",
                        subtitle: crust.priceModifier ?? 0 > 0 ? "+ \(formatCurrency(crust.priceModifier ?? 0))" : nil,
                        isSelected: selectedCrustId == crust.id
                    ) {
                        selectedCrustId = crust.id
                    }
                }
            }
        }
        .padding(12)
        .background(AppColors.surface)
        .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))
    }

    var stepFlavors: some View {
        let flavorItems = flavors
        return VStack(alignment: .leading, spacing: 10) {
            Text("4. Sabores (\(selectedFlavorIds.count)/\(maxFlavorsAllowed))")
                .font(AppTypography.heading3)
                .foregroundStyle(AppColors.textPrimary)

            Text("Toque no sabor para escolher adicionais.")
                .font(.caption)
                .foregroundStyle(AppColors.textMuted)

            ForEach(Array(flavorItems.indices), id: \.self) { index in
                let flavor = flavorItems[index]
                let isSelected = selectedFlavorIds.contains(flavor.id)
                let price = selectedSizeId.flatMap { flavor.pizzaPrices[$0] } ?? flavor.price
                let maxReached = selectedFlavorIds.count >= maxFlavorsAllowed
                let disableSwitch = isSelected == false && maxReached

                HStack(spacing: 10) {
                    VStack(alignment: .leading, spacing: 4) {
                        Text(flavor.name)
                            .font(AppTypography.body)
                            .foregroundStyle(AppColors.textPrimary)
                        if let price {
                            Text(formatCurrency(price))
                                .font(.caption)
                                .foregroundStyle(AppColors.textMuted)
                        }
                    }

                    Spacer()

                    Toggle("", isOn: Binding(
                        get: { isSelected },
                        set: { value in
                            if value {
                                addFlavor(flavor.id)
                            } else {
                                removeFlavor(flavor.id)
                            }
                        }
                    ))
                    .labelsHidden()
                    .disabled(disableSwitch)
                }
                .padding(.vertical, 2)
                .contentShape(Rectangle())
                .onTapGesture {
                    guard isSelected else { return }
                    guard flavor.addonGroups.contains(where: { $0.items.isEmpty == false }) else { return }
                    selectedFlavorForAddons = flavor
                }
            }
        }
        .padding(12)
        .background(AppColors.surface)
        .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))
    }

    func sizeRow(_ size: StorePizzaSize) -> some View {
        let title = size.name ?? "Tamanho"
        let subtitle = "Até \(max(1, size.maxFlavors ?? 1)) sabor(es)"
        let selected = selectedSizeId == size.id

        return radioRow(
            title: title,
            subtitle: subtitle,
            isSelected: selected
        ) {
            selectedSizeId = size.id
        }
    }

    func radioRow(title: String, subtitle: String?, isSelected: Bool, action: @escaping () -> Void) -> some View {
        Button(action: action) {
            HStack(spacing: 10) {
                ZStack {
                    Circle()
                        .stroke(isSelected ? AppColors.primary : AppColors.textMuted.opacity(0.4), lineWidth: 2)
                        .frame(width: 20, height: 20)
                    if isSelected {
                        Circle()
                            .fill(AppColors.primary)
                            .frame(width: 10, height: 10)
                    }
                }

                VStack(alignment: .leading, spacing: 2) {
                    Text(title)
                        .font(AppTypography.body)
                        .foregroundStyle(AppColors.textPrimary)
                    if let subtitle, subtitle.isEmpty == false {
                        Text(subtitle)
                            .font(.caption)
                            .foregroundStyle(AppColors.textMuted)
                    }
                }

                Spacer()
            }
            .contentShape(Rectangle())
        }
        .buttonStyle(.plain)
    }

    func crustDescription(_ crust: StorePizzaCrust?) -> String {
        guard let crust else { return "Sem borda especial" }
        let name = crust.name ?? "Borda"
        let modifier = crust.priceModifier ?? 0
        if modifier > 0 {
            return "\(name) (+ \(formatCurrency(modifier)))"
        }
        return name
    }

    func applyAutoSelections() {
        if selectedSizeId != nil {
            if doughs.count == 1 {
                selectedDoughId = doughs.first?.id
            } else if doughs.isEmpty {
                selectedDoughId = "__none__"
            }
        }

        if isDoughReady {
            if crusts.count == 1 {
                selectedCrustId = crusts.first?.id
            } else if crusts.isEmpty {
                selectedCrustId = "__none__"
            }
        }
    }

    func trimFlavorSelectionByLimit() {
        let limit = maxFlavorsAllowed
        guard selectedFlavorIds.count > limit else { return }
        let sorted = selectedFlavorIds.sorted()
        selectedFlavorIds = Set(sorted.prefix(limit))
    }

    func addFlavor(_ flavorId: String) {
        if selectedFlavorIds.contains(flavorId) { return }
        if selectedFlavorIds.count >= maxFlavorsAllowed { return }
        selectedFlavorIds.insert(flavorId)
    }

    func removeFlavor(_ flavorId: String) {
        selectedFlavorIds.remove(flavorId)
        flavorAddonQuantities.removeValue(forKey: flavorId)
    }

    func formatCurrency(_ value: Double) -> String {
        String(format: "R$ %.2f", value).replacingOccurrences(of: ".", with: ",")
    }
}