import ByreAPI
import SwiftUI
import UserNotifications

typealias NotificationPrefs = Components.Schemas.NotificationPrefs

@MainActor
private let kinds: [(key: WritableKeyPath<NotificationPrefs, Bool>, label: String)] = [
    (\.questions, "Questions"),
    (\.reports, "Turn summaries"),
    (\.ready, "Ready to merge"),
    (\.discard, "Suggests discard"),
    (\.mergeProblems, "Merge problems"),
    (\.workflows, "Workflow finished"),
    (\.errors, "Session errors"),
    (\.rateLimits, "Rate limits"),
]

struct SettingsView: View {
    @Environment(Store.self) private var store

    var body: some View {
        ScrollView {
            VStack(alignment: .leading, spacing: 0) {
                heading("Window colour")
                Text("Windows for this server have a border in this colour, on every Mac you use.")
                    .foregroundStyle(Palette.muted)
                    .fixedSize(horizontal: false, vertical: true)
                ServerColorPicker()
                heading("Notifications")
                DeviceNotifications()
                PrefsBox()
                heading("Default model")
                Text("New tasks you start from byre run on this model.")
                    .foregroundStyle(Palette.muted)
                    .fixedSize(horizontal: false, vertical: true)
                ModelMenu(current: store.defaultModel, help: "Model for new tasks") { m in
                    try await store.api.client.updateDefaultModel(body: .json(.init(model: m))).ok.body.json
                }
                if let me = store.me {
                    heading("Review models")
                    Text("The first model reviews your tasks' work. The second reviews work the first model wrote.")
                        .foregroundStyle(Palette.muted)
                        .fixedSize(horizontal: false, vertical: true)
                    ModelMenu(current: me.reviewModel, help: "Model that reviews your tasks") { m in
                        try await store.api.client.updateReviewModels(body: .json(.init(reviewModel: m, secondReviewModel: me.secondReviewModel))).ok.body.json
                    }
                    ModelMenu(current: me.secondReviewModel, help: "Model that reviews work the first review model wrote") { m in
                        try await store.api.client.updateReviewModels(body: .json(.init(reviewModel: me.reviewModel, secondReviewModel: m))).ok.body.json
                    }
                }
                heading("This Mac's permissions")
                Text("The macOS privacy grants byre's app needs for agents to see and control this Mac. Checking asks macOS for any that are missing.")
                    .foregroundStyle(Palette.muted)
                    .fixedSize(horizontal: false, vertical: true)
                PermissionsCheck(run: checkLocalPermissions)
            }
            .padding(.horizontal, 16)
            .padding(.top, 8)
            .padding(.bottom, 16)
            .frame(maxWidth: .infinity, alignment: .leading)
        }
        .frame(maxWidth: .infinity, maxHeight: .infinity)
        .background(Palette.bg)
    }

    private func heading(_ text: String) -> some View {
        Text(text)
            .font(Fonts.font(13, weight: 700))
            .padding(.top, 16)
            .padding(.bottom, 6)
    }
}

private struct ServerColorPicker: View {
    @Environment(Store.self) private var store

    var body: some View {
        let origin = store.api.origin.absoluteString
        let current = Servers.shared.record(origin)?.color
        HStack(spacing: 4) {
            ForEach(taskPalette.indices, id: \.self) { i in
                Button {
                    Servers.shared.setColor(origin, i)
                } label: {
                    Circle()
                        .fill(taskPalette[i])
                        .frame(width: 18, height: 18)
                        .padding(3)
                        .overlay(Circle().stroke(i == current ? Palette.text : .clear, lineWidth: 1.5))
                        .contentShape(Circle())
                }
                .buttonStyle(.plain)
            }
        }
        .padding(.top, 8)
    }
}

private struct DeviceNotifications: View {
    @ViewState private var status: UNAuthorizationStatus?
    @ViewState private var asking = false

    var body: some View {
        Group {
            switch status {
            case .none:
                EmptyView()
            case .denied:
                Text("Notifications are blocked for byre in System Settings.").foregroundStyle(Palette.muted)
            case .authorized, .provisional:
                Text("This Mac shows notifications while byre is running.")
            default:
                VStack(alignment: .leading, spacing: 8) {
                    Text("This Mac doesn't show notifications from byre.")
                    Button("Turn on for this Mac") {
                        asking = true
                        Task {
                            _ = try? await UNUserNotificationCenter.current().requestAuthorization(options: [.alert, .sound])
                            await read()
                            asking = false
                        }
                    }
                    .buttonStyle(WebButtonStyle())
                    .disabled(asking)
                }
            }
        }
        .padding(.bottom, 8)
        .task {
            await read()
        }
        .onReceive(NotificationCenter.default.publisher(for: NSApplication.didBecomeActiveNotification)) { _ in
            Task {
                await read()
            }
        }
    }

    private func read() async {
        status = await UNUserNotificationCenter.current().notificationSettings().authorizationStatus
    }
}

private struct PrefsBox: View {
    @Environment(Store.self) private var store
    @Environment(Overlays.self) private var overlays

    var body: some View {
        if let me = store.me {
            VStack(alignment: .leading, spacing: 4) {
                Text("Notify me about")
                    .foregroundStyle(Palette.muted)
                    .padding(.horizontal, 4)
                    .background(Palette.bg)
                    .offset(y: -18)
                    .padding(.bottom, -18)
                ForEach(kinds, id: \.label) { kind in
                    Toggle(kind.label, isOn: Binding(get: { me.notificationPrefs[keyPath: kind.key] }, set: { on in
                        var prefs = me.notificationPrefs
                        prefs[keyPath: kind.key] = on
                        Task {
                            do {
                                store.me = try await store.api.client.updateNotificationPrefs(body: .json(prefs)).ok.body.json
                            } catch {
                                overlays.showAlert(errorText(error))
                            }
                        }
                    }))
                    .toggleStyle(.checkbox)
                    .tint(Palette.accent)
                }
            }
            .padding(.horizontal, 12)
            .padding(.top, 8)
            .padding(.bottom, 10)
            .frame(maxWidth: .infinity, alignment: .leading)
            .background(RoundedRectangle(cornerRadius: 8).stroke(Palette.border))
            .padding(.top, 16)
        }
    }
}

private struct ModelMenu: View {
    let current: String
    let help: String
    let pick: (String) async throws -> User
    @Environment(Store.self) private var store
    @Environment(Overlays.self) private var overlays

    var body: some View {
        Menu {
            ForEach(models, id: \.self) { m in
                Button(m) {
                    Task {
                        do {
                            store.me = try await pick(m)
                        } catch {
                            overlays.showAlert(errorText(error))
                        }
                    }
                }
            }
        } label: {
            HStack(spacing: 8) {
                Text(current)
                Image(systemName: "chevron.up.chevron.down")
                    .font(.system(size: 9, weight: .semibold))
            }
            .foregroundStyle(Palette.text)
            .modifier(FieldStyle())
            .contentShape(Rectangle())
        }
        .menuStyle(.button)
        .buttonStyle(.plain)
        .menuIndicator(.hidden)
        .fixedSize()
        .help(help)
        .padding(.top, 8)
    }
}