import SwiftUI
import WatchKit

/// Routine quotidienne sur la montre : les exercices, cochables un par un au fil
/// de la séance. Chaque coche part vers l'iPhone, qui la POSTe au serveur —
/// l'état est donc partagé avec la page /routine et le widget de la home.
struct RoutineView: View {
    @StateObject private var store = RoutineStore.shared
    @State private var guided: RoutineBlock?

    var body: some View {
        Group {
            if store.isEmpty {
                emptyState
            } else {
                list
            }
        }
        .navigationTitle("Routine")
        .sheet(item: $guided) { block in
            RoutineGuidedView(block: block)
        }
    }

    private var emptyState: some View {
        VStack(spacing: 8) {
            Image(systemName: "figure.cooldown")
                .font(.title2)
                .foregroundStyle(.secondary)
            Text("Ouvre l'app Coach sur l'iPhone une fois pour recevoir la routine.")
                .font(.footnote)
                .multilineTextAlignment(.center)
                .foregroundStyle(.secondary)
        }
        .padding()
    }

    private var list: some View {
        ScrollView {
            LazyVStack(spacing: 6, pinnedViews: []) {
                progressHeader

                ForEach(store.morningBlocks) { block in
                    blockSection(block)
                }

                if !store.otherBlocks.isEmpty {
                    Text("APRÈS LA COURSE")
                        .font(.caption2)
                        .foregroundStyle(.orange)
                        .frame(maxWidth: .infinity, alignment: .leading)
                        .padding(.top, 8)
                    ForEach(store.otherBlocks) { block in
                        blockSection(block)
                    }
                }

                if store.lastSyncFailed {
                    Button {
                        store.retry()
                    } label: {
                        Label("Renvoyer vers l'iPhone", systemImage: "arrow.clockwise")
                            .font(.footnote)
                    }
                    .tint(.orange)
                    .padding(.top, 4)
                }
            }
            .padding(.horizontal, 4)
        }
    }

    private var progressHeader: some View {
        let total = store.totalExercises
        let count = store.done.count
        return VStack(spacing: 4) {
            Text("\(count) / \(total) exercices")
                .font(.headline)
                .foregroundStyle(count == total && total > 0 ? .green : .primary)
            ProgressView(value: total > 0 ? Double(count) / Double(total) : 0)
                .tint(.cyan)
        }
        .padding(.vertical, 4)
    }

    /// En-tête de bloc (tap = tout cocher d'un coup), bouton de séance guidée,
    /// puis ses exercices.
    private func blockSection(_ block: RoutineBlock) -> some View {
        let complete = store.isComplete(block)
        return VStack(spacing: 4) {
            Button {
                store.toggleBlock(block)
                WKInterfaceDevice.current().play(complete ? .click : .success)
            } label: {
                HStack(spacing: 6) {
                    Text("\(block.num). \(block.title)")
                        .font(.caption)
                        .fontWeight(.semibold)
                        .multilineTextAlignment(.leading)
                    Spacer(minLength: 0)
                    Text("\(store.doneCount(in: block))/\(block.items.count)")
                        .font(.caption2)
                        .monospacedDigit()
                        .foregroundStyle(complete ? .green : .secondary)
                }
                .frame(maxWidth: .infinity, alignment: .leading)
            }
            .buttonStyle(.plain)
            .padding(.top, 6)

            Button {
                guided = block
            } label: {
                Label("Démarrer", systemImage: "play.fill")
                    .font(.caption2)
                    .frame(maxWidth: .infinity)
            }
            .tint(.cyan)

            ForEach(block.items) { item in
                exerciseRow(item)
            }
        }
    }

    private func exerciseRow(_ item: RoutineExercise) -> some View {
        let isDone = store.done.contains(item.id)
        return Button {
            store.toggle(item.id)
            WKInterfaceDevice.current().play(isDone ? .click : .success)
        } label: {
            HStack(spacing: 8) {
                Image(systemName: isDone ? "checkmark.circle.fill" : "circle")
                    .foregroundStyle(isDone ? .green : .secondary)
                VStack(alignment: .leading, spacing: 1) {
                    Text(item.name)
                        .font(.footnote)
                        .multilineTextAlignment(.leading)
                        .strikethrough(isDone, color: .secondary)
                    if !item.dose.isEmpty {
                        Text(item.dose)
                            .font(.caption2)
                            .foregroundStyle(.secondary)
                    }
                }
                Spacer(minLength: 0)
            }
            .frame(maxWidth: .infinity, alignment: .leading)
        }
        .buttonStyle(.plain)
        .padding(.vertical, 6)
        .padding(.horizontal, 8)
        .background(Color.gray.opacity(isDone ? 0.10 : 0.18), in: RoundedRectangle(cornerRadius: 8))
        .opacity(isDone ? 0.65 : 1)
    }
}