import WidgetKit
import SwiftUI
import SwiftData
import SharedModels
import os

private let logger = Logger(subsystem: "com.conjuga.app.widget", category: "WordOfDay")

struct WordOfDayEntry: TimelineEntry {
    let date: Date
    let word: WordOfDay?
}

struct WordOfDayProvider: TimelineProvider {
    func placeholder(in context: Context) -> WordOfDayEntry {
        WordOfDayEntry(date: Date(), word: WordOfDay(spanish: "hablar", english: "to speak", weekNumber: 1))
    }

    private static let previewWord = WordOfDay(spanish: "hablar", english: "to speak", weekNumber: 1)

    func getSnapshot(in context: Context, completion: @escaping (WordOfDayEntry) -> Void) {
        if context.isPreview {
            completion(WordOfDayEntry(date: Date(), word: Self.previewWord))
            return
        }
        let word = fetchWordOfDay(for: Date()) ?? Self.previewWord
        completion(WordOfDayEntry(date: Date(), word: word))
    }

    func getTimeline(in context: Context, completion: @escaping (Timeline<WordOfDayEntry>) -> Void) {
        let word = fetchWordOfDay(for: Date()) ?? Self.previewWord
        let entry = WordOfDayEntry(date: Date(), word: word)

        let tomorrow = Calendar.current.startOfDay(
            for: Calendar.current.date(byAdding: .day, value: 1, to: Date())!
        )
        completion(Timeline(entries: [entry], policy: .after(tomorrow)))
    }

    private func fetchWordOfDay(for date: Date) -> WordOfDay? {
        let localURL = FileManager.default.containerURL(forSecurityApplicationGroupIdentifier: "group.com.conjuga.app")!.appendingPathComponent("local.store")
        logger.info("Store path: \(localURL.path)")
        logger.info("Store exists: \(FileManager.default.fileExists(atPath: localURL.path))")

        if !FileManager.default.fileExists(atPath: localURL.path) {
            let dir = localURL.deletingLastPathComponent()
            let contents = (try? FileManager.default.contentsOfDirectory(atPath: dir.path)) ?? []
            logger.error("local.store NOT FOUND. App Support contents: \(contents.joined(separator: ", "))")
            return nil
        }

        do {
            let container = try ModelContainer(
                for: VocabCard.self, CourseDeck.self,
                configurations: ModelConfiguration(
                    "local",
                    url: localURL,
                    cloudKitDatabase: .none
                )
            )
            logger.info("ModelContainer opened OK")

            let context = ModelContext(container)
            let wordOffset = UserDefaults(suiteName: "group.com.conjuga.app")?.integer(forKey: "wordOffset") ?? 0
            guard let card = CourseCardStore.fetchWordOfDayCard(for: date, wordOffset: wordOffset, context: context) else {
                logger.error("Store has 0 VocabCards")
                return nil
            }

            logger.info("Picked card: \(card.front) = \(card.back)")

            let deckId = card.deckId
            let deckDescriptor = FetchDescriptor<CourseDeck>(
                predicate: #Predicate<CourseDeck> { $0.id == deckId }
            )
            let week = (try? context.fetch(deckDescriptor))?.first?.weekNumber ?? 1

            return WordOfDay(spanish: card.front, english: card.back, weekNumber: week)
        } catch {
            logger.error("Failed: \(error.localizedDescription)")
            return nil
        }
    }
}

struct WordOfDayWidget: Widget {
    let kind = "WordOfDayWidget"

    var body: some WidgetConfiguration {
        StaticConfiguration(kind: kind, provider: WordOfDayProvider()) { entry in
            WordOfDayWidgetView(entry: entry)
                .containerBackground(.fill.tertiary, for: .widget)
        }
        .configurationDisplayName("Word of the Day")
        .description("Learn a new Spanish word every day.")
        .supportedFamilies([.systemSmall, .systemMedium])
    }
}

struct WordOfDayWidgetView: View {
    @Environment(\.widgetFamily) var family
    let entry: WordOfDayEntry

    var body: some View {
        if let word = entry.word {
            switch family {
            case .systemSmall:
                smallView(word: word)
            case .systemMedium:
                mediumView(word: word)
            default:
                smallView(word: word)
            }
        } else {
            VStack {
                Image(systemName: "textformat.abc")
                    .font(.title)
                    .foregroundStyle(.secondary)
                Text("Open Conjuga to start")
                    .font(.caption)
                    .foregroundStyle(.secondary)
            }
        }
    }

    private func smallView(word: WordOfDay) -> some View {
        VStack(spacing: 8) {
            Text("Word of the Day")
                .font(.caption2)
                .foregroundStyle(.secondary)
                .textCase(.uppercase)

            Text(word.spanish)
                .font(.title2.bold())
                .minimumScaleFactor(0.6)
                .lineLimit(1)

            Text(word.english)
                .font(.subheadline)
                .foregroundStyle(.secondary)
                .minimumScaleFactor(0.6)
                .lineLimit(2)
                .multilineTextAlignment(.center)

            Text("Week \(word.weekNumber)")
                .font(.caption2)
                .foregroundStyle(.orange)
        }
    }

    private func mediumView(word: WordOfDay) -> some View {
        HStack(spacing: 16) {
            VStack(spacing: 4) {
                Text("WORD OF THE DAY")
                    .font(.caption2.weight(.semibold))
                    .foregroundStyle(.orange)

                Text(word.spanish)
                    .font(.largeTitle.bold())
                    .minimumScaleFactor(0.5)
                    .lineLimit(1)
            }
            .frame(maxWidth: .infinity)

            Divider()

            VStack(alignment: .leading, spacing: 8) {
                VStack(alignment: .leading, spacing: 2) {
                    Text("English")
                        .font(.caption2)
                        .foregroundStyle(.secondary)
                    Text(word.english)
                        .font(.headline)
                        .lineLimit(2)
                }

                HStack {
                    Image(systemName: "calendar")
                        .font(.caption2)
                    Text("Week \(word.weekNumber)")
                        .font(.caption2)
                }
                .foregroundStyle(.secondary)
            }
            .frame(maxWidth: .infinity, alignment: .leading)
        }
        .padding(.horizontal, 4)
    }
}

#Preview(as: .systemSmall) {
    WordOfDayWidget()
} timeline: {
    WordOfDayEntry(date: Date(), word: WordOfDay(spanish: "hablar", english: "to speak", weekNumber: 1))
}

#Preview(as: .systemMedium) {
    WordOfDayWidget()
} timeline: {
    WordOfDayEntry(date: Date(), word: WordOfDay(spanish: "hablar", english: "to speak", weekNumber: 1))
}