//
//  TrackReaderView.swift
//  Bible-Week
//
//  Leitura de uma trilha do dia: carrega os capítulos em sequência
//  e permite marcar a trilha como concluída.
//

import SwiftUI

struct TrackReaderView: View {
    let day: Int
    let reading: TrackReading
    @Bindable var plan: ReadingPlanState

    @State private var chapters: [Chapter] = []
    @State private var isLoading = false
    @State private var errorMessage: String?

    private var isCompleted: Bool {
        plan.isCompleted(day: day, track: reading.track)
    }

    var body: some View {
        Group {
            if isLoading {
                ProgressView("Carregando leitura...")
            } else if let errorMessage {
                ContentUnavailableView {
                    Label("Erro ao carregar", systemImage: "exclamationmark.triangle")
                } description: {
                    Text(errorMessage)
                } actions: {
                    Button("Tentar novamente") { Task { await load() } }
                }
            } else {
                content
            }
        }
        .navigationTitle(reading.label)
        .navigationBarTitleDisplayMode(.inline)
        .safeAreaInset(edge: .bottom) {
            markButton
        }
        .task { await load() }
    }

    private var content: some View {
        ScrollView {
            LazyVStack(alignment: .leading, spacing: 16) {
                ForEach(chapters, id: \.self) { chapter in
                    Text("\(chapter.bookName) \(chapter.chapter)")
                        .font(.title3.bold())
                        .padding(.top, 8)
                    ForEach(chapter.verses) { verse in
                        Text("\(Text("\(verse.verse)").font(.caption2).foregroundColor(.accentColor).baselineOffset(4)) \(verse.text)")
                            .font(.body)
                            .fixedSize(horizontal: false, vertical: true)
                    }
                }
            }
            .padding()
            .frame(maxWidth: .infinity, alignment: .leading)
        }
    }

    private var markButton: some View {
        Button {
            toggleCompletion()
        } label: {
            Label(
                isCompleted ? "Concluído" : "Marcar como concluído",
                systemImage: isCompleted ? "checkmark.circle.fill" : "circle"
            )
            .frame(maxWidth: .infinity)
        }
        .buttonStyle(.borderedProminent)
        .tint(isCompleted ? .green : .accentColor)
        .controlSize(.large)
        .padding()
        .background(.bar)
        .accessibilityLabel(
            isCompleted
                ? "\(reading.track.displayName) concluída. Toque para desmarcar."
                : "Marcar \(reading.track.displayName) como concluída"
        )
    }

    private func toggleCompletion() {
        withAnimation {
            plan.setCompleted(!isCompleted, day: day, track: reading.track)
        }
        if plan.isCompleted {
            // Plano 180/180 concluído: remove o lembrete diário.
            ReadingReminderService.cancelDailyReminder()
        }
    }

    private func load() async {
        isLoading = true
        errorMessage = nil
        defer { isLoading = false }
        do {
            var loaded: [Chapter] = []
            for ref in reading.chapters {
                loaded.append(try await BibleAPI.chapter(book: ref.bookCode, chapter: ref.chapter))
            }
            chapters = loaded
        } catch {
            errorMessage = "Verifique sua conexão e tente novamente."
        }
    }
}