import WidgetKit
import SwiftUI
import Foundation

// MARK: - Shared data model (mirrors WidgetDataStore in main app)

private struct TodayMealData: Codable {
    let lunch: String?
    let dinner: String?
    let lunchLabel: String
    let dinnerLabel: String
    let weekdayName: String
    let updatedAt: Date
}

private enum WidgetStore {
    static let appGroupID = "group.com.alexandrevazquez.mealmood"
    static let key = "mealmood.today_meals"

    static func read() -> TodayMealData? {
        guard let defaults = UserDefaults(suiteName: appGroupID),
              let data = defaults.data(forKey: key) else { return nil }
        return try? JSONDecoder().decode(TodayMealData.self, from: data)
    }
}

// MARK: - Timeline

struct TodayMealEntry: TimelineEntry {
    let date: Date
    let lunch: String?
    let dinner: String?
    let lunchLabel: String
    let dinnerLabel: String
    let weekdayName: String
}

struct Provider: TimelineProvider {
    func placeholder(in context: Context) -> TodayMealEntry {
        TodayMealEntry(date: Date(), lunch: "Pasta al pesto", dinner: "Salmón al horno",
                       lunchLabel: "Comida", dinnerLabel: "Cena", weekdayName: "Lunes")
    }

    func getSnapshot(in context: Context, completion: @escaping (TodayMealEntry) -> Void) {
        let data = WidgetStore.read()
        completion(entry(from: data))
    }

    func getTimeline(in context: Context, completion: @escaping (Timeline<TodayMealEntry>) -> Void) {
        let data = WidgetStore.read()
        let nextMidnight = Calendar.current.startOfDay(for: Calendar.current.date(byAdding: .day, value: 1, to: Date())!)
        completion(Timeline(entries: [entry(from: data)], policy: .after(nextMidnight)))
    }

    private func entry(from data: TodayMealData?) -> TodayMealEntry {
        TodayMealEntry(
            date: Date(),
            lunch: data?.lunch,
            dinner: data?.dinner,
            lunchLabel: data?.lunchLabel ?? "Lunch",
            dinnerLabel: data?.dinnerLabel ?? "Dinner",
            weekdayName: data?.weekdayName ?? ""
        )
    }
}

// MARK: - Colors

private extension Color {
    static let mmCoral    = Color(red: 0.93, green: 0.42, blue: 0.31)
    static let mmBgWarm   = Color(red: 1.00, green: 0.94, blue: 0.91)
    static let mmBgMint   = Color(red: 0.93, green: 0.98, blue: 0.95)
    static let mmText     = Color(red: 0.13, green: 0.13, blue: 0.13)
    static let mmSubtext  = Color(red: 0.55, green: 0.55, blue: 0.55)
    static let mmLunchOrange = Color(red: 0.90, green: 0.55, blue: 0.18)
    static let mmDinnerBlue  = Color(red: 0.36, green: 0.48, blue: 0.78)
}

// MARK: - Small widget

private struct SmallWidgetView: View {
    let entry: TodayMealEntry

    var body: some View {
        VStack(alignment: .leading, spacing: 0) {
            HStack(spacing: 4) {
                Image(systemName: "fork.knife")
                    .font(.system(size: 10, weight: .bold))
                    .foregroundColor(.mmCoral)
                Text("MealMood")
                    .font(.system(size: 11, weight: .bold))
                    .foregroundColor(.mmCoral)
                Spacer()
            }

            Text(entry.weekdayName)
                .font(.system(size: 10, weight: .medium))
                .foregroundColor(.mmSubtext)
                .lineLimit(1)
                .padding(.top, 2)
                .padding(.bottom, 10)

            Spacer()

            mealRow(icon: "sun.max.fill", label: entry.lunchLabel,
                    name: entry.lunch, color: .mmLunchOrange)
                .padding(.bottom, 8)

            mealRow(icon: "moon.stars.fill", label: entry.dinnerLabel,
                    name: entry.dinner, color: .mmDinnerBlue)
        }
        .padding(12)
        .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .leading)
        .background(
            LinearGradient(colors: [.mmBgWarm, .mmBgMint],
                           startPoint: .topLeading, endPoint: .bottomTrailing)
        )
    }

    private func mealRow(icon: String, label: String, name: String?, color: Color) -> some View {
        HStack(spacing: 8) {
            Image(systemName: icon)
                .font(.system(size: 13))
                .foregroundColor(color)
                .frame(width: 18)
            VStack(alignment: .leading, spacing: 1) {
                Text(label.uppercased())
                    .font(.system(size: 8, weight: .semibold))
                    .foregroundColor(.mmSubtext)
                Text(name ?? "—")
                    .font(.system(size: 13, weight: .semibold))
                    .foregroundColor(.mmText)
                    .lineLimit(2)
                    .minimumScaleFactor(0.75)
            }
        }
    }
}

// MARK: - Medium widget

private struct MediumWidgetView: View {
    let entry: TodayMealEntry

    var body: some View {
        HStack(spacing: 0) {
            VStack(alignment: .leading, spacing: 6) {
                Image(systemName: "fork.knife")
                    .font(.system(size: 18, weight: .bold))
                    .foregroundColor(.mmCoral)
                Spacer()
                Text(entry.weekdayName)
                    .font(.system(size: 16, weight: .bold))
                    .foregroundColor(.mmText)
                    .lineLimit(1)
                    .minimumScaleFactor(0.7)
                Text(Date(), style: .date)
                    .font(.system(size: 11, weight: .medium))
                    .foregroundColor(.mmSubtext)
            }
            .padding(14)
            .frame(width: 112)
            .frame(maxHeight: .infinity, alignment: .leading)
            .background(Color.mmBgWarm)

            Rectangle()
                .fill(Color.mmCoral.opacity(0.2))
                .frame(width: 1)

            VStack(alignment: .leading, spacing: 14) {
                mediumRow(icon: "sun.max.fill", label: entry.lunchLabel,
                          name: entry.lunch, color: .mmLunchOrange)
                Divider()
                mediumRow(icon: "moon.stars.fill", label: entry.dinnerLabel,
                          name: entry.dinner, color: .mmDinnerBlue)
            }
            .padding(14)
            .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .leading)
            .background(Color.white)
        }
    }

    private func mediumRow(icon: String, label: String, name: String?, color: Color) -> some View {
        HStack(spacing: 10) {
            Image(systemName: icon)
                .font(.system(size: 16))
                .foregroundColor(color)
                .frame(width: 22)
            VStack(alignment: .leading, spacing: 2) {
                Text(label.uppercased())
                    .font(.system(size: 9, weight: .semibold))
                    .foregroundColor(.mmSubtext)
                Text(name ?? "—")
                    .font(.system(size: 15, weight: .semibold))
                    .foregroundColor(.mmText)
                    .lineLimit(2)
            }
        }
    }
}

// MARK: - Widget entry view

struct MealMoodWidgetView: View {
    var entry: Provider.Entry
    @Environment(\.widgetFamily) var family

    var body: some View {
        switch family {
        case .systemMedium:
            MediumWidgetView(entry: entry)
        default:
            SmallWidgetView(entry: entry)
        }
    }
}

// MARK: - Widget definition

@main
struct MealMoodWidget: Widget {
    let kind = "MealMoodWidget"

    var body: some WidgetConfiguration {
        StaticConfiguration(kind: kind, provider: Provider()) { entry in
            MealMoodWidgetView(entry: entry)
                .containerBackground(for: .widget) { Color.white }
        }
        .configurationDisplayName("MealMood")
        .description("Today's lunch and dinner at a glance.")
        .supportedFamilies([.systemSmall, .systemMedium])
    }
}