import MusicAssistantCore
import SwiftUI

struct ArabicLyricsReviewView: View {
    @Binding var project: SongProject

    private let processor = ArabicPronunciationProcessor()

    @State private var processedLyrics = ""
    @State private var processingNotes: [ArabicPronunciationProcessingNote] = []

    var body: some View {
        VStack(alignment: .leading, spacing: 10) {
            HStack {
                Text("Arabic lyrics review")
                    .font(.headline)

                Spacer()

                Button(action: refreshProcessedLyrics) {
                    Label("Refresh processed lyrics", systemImage: "arrow.clockwise")
                        .labelStyle(.iconOnly)
                }
                .buttonStyle(.borderless)
                .help("Refresh processed lyrics")
            }

            Text("Original lyrics")
                .font(.subheadline)
                .foregroundStyle(.secondary)

            TextEditor(text: .constant(project.lyrics.text))
                .font(.body)
                .frame(minHeight: 96)
                .disabled(true)

            Text("Processed lyrics")
                .font(.subheadline)
                .foregroundStyle(.secondary)

            TextEditor(text: $processedLyrics)
                .font(.body)
                .frame(minHeight: 96)

            ForEach(Array(processingNotes.enumerated()), id: \.offset) { entry in
                Label(entry.element.title, systemImage: entry.element.systemImage)
                    .font(.caption)
                    .foregroundStyle(.secondary)
            }

            Button(action: applyProcessedLyrics) {
                Label("Use processed lyrics", systemImage: "checkmark.circle")
            }
            .disabled(!canApplyProcessedLyrics)
        }
        .onAppear(perform: refreshProcessedLyrics)
    }

    private var canApplyProcessedLyrics: Bool {
        let trimmedLyrics = processedLyrics.trimmingCharacters(in: .whitespacesAndNewlines)
        return !trimmedLyrics.isEmpty && processedLyrics != project.lyrics.text
    }

    private func refreshProcessedLyrics() {
        let result = processor.process(
            lyrics: project.lyrics.text,
            settings: project.arabicPronunciationSettings
        )
        processedLyrics = result.text
        processingNotes = result.notes
    }

    private func applyProcessedLyrics() {
        project.applyReviewedArabicLyrics(processedLyrics)
    }
}

private extension ArabicPronunciationProcessingNote {
    var title: String {
        switch self {
        case .processingDisabled:
            return "Arabic processing is disabled"
        case .diacritizationPolicyUnspecified:
            return "Select a diacritics policy to continue"
        case .pronunciationTargetedDiacriticsNeedReview:
            return "Targeted diacritics need review"
        case .fullTashkeelNeedsReview:
            return "Full tashkeel needs review"
        case .tanweenAdditionNeedsReview:
            return "Tanween addition needs review"
        case let .preservedSpellingsProtected(count):
            return "Protected \(count) preserved spelling\(count == 1 ? "" : "s")"
        }
    }

    var systemImage: String {
        switch self {
        case .processingDisabled, .diacritizationPolicyUnspecified:
            return "info.circle"
        case .pronunciationTargetedDiacriticsNeedReview,
             .fullTashkeelNeedsReview,
             .tanweenAdditionNeedsReview:
            return "exclamationmark.triangle"
        case .preservedSpellingsProtected:
            return "checkmark.shield"
        }
    }
}