//
//  AppSelectionSheet.swift
//  Severed
//

import FamilyControls
import SwiftUI

/// App/category/website selection for a rule. Wraps Apple's
/// `FamilyActivityPicker` (the system-sanctioned way to choose apps without
/// seeing their identities) and adds the reference app's Block / Allow Only
/// mode switch.
struct AppSelectionSheet: View {
    @Binding var draft: RuleDraft
    @Environment(\.dismiss) private var dismiss

    @State private var selection: FamilyActivitySelection
    @State private var mode: SelectionMode

    init(draft: Binding<RuleDraft>) {
        self._draft = draft
        self._selection = State(
            initialValue: AppSelectionCodec.decode(draft.wrappedValue.selectionData)
        )
        self._mode = State(initialValue: draft.wrappedValue.selectionMode)
    }

    var body: some View {
        VStack(spacing: 0) {
            HStack {
                CircleIconButton(systemImage: "chevron.left") { dismiss() }
                    .accessibilityIdentifier("selectionBackButton")
                Spacer()
                CircleIconButton(systemImage: "checkmark", tint: .black) { save() }
                    .background(Theme.accent, in: Circle())
                    .accessibilityIdentifier("confirmSelectionButton")
            }
            .overlay(
                Text("Selected")
                    .font(.system(size: 18, weight: .semibold))
                    .foregroundStyle(.white)
            )
            .padding(.horizontal, 20)
            .padding(.top, 18)

            Picker("Mode", selection: $mode) {
                ForEach(SelectionMode.allCases, id: \.self) { mode in
                    Text(mode.displayName).tag(mode)
                }
            }
            .pickerStyle(.segmented)
            .padding(.horizontal, 20)
            .padding(.top, 16)
            .accessibilityIdentifier("selectionModePicker")

            FamilyActivityPicker(selection: $selection)
                .padding(.top, 4)

            VStack(spacing: 10) {
                Text(selectionSummary)
                    .font(.system(size: 14))
                    .foregroundStyle(Theme.textSecondary)
                    .accessibilityIdentifier("selectionCountLabel")
                Button {
                    save()
                } label: {
                    Text("Save")
                        .font(.system(size: 17, weight: .semibold))
                        .foregroundStyle(.black)
                        .frame(maxWidth: .infinity)
                        .frame(height: 54)
                        .background(.white, in: RoundedRectangle(cornerRadius: 27))
                }
                .buttonStyle(.plain)
                .accessibilityIdentifier("saveSelectionButton")
            }
            .padding(.horizontal, 20)
            .padding(.bottom, 16)
        }
        .background(Theme.background)
    }

    private var selectionSummary: String {
        let count = AppSelectionCodec.count(of: selection)
        return count == 1 ? "1 App Selected" : "\(count) Apps Selected"
    }

    private func save() {
        draft.selectionData = AppSelectionCodec.encode(selection)
        draft.selectionCount = AppSelectionCodec.count(of: selection)
        draft.selectionMode = mode
        dismiss()
    }
}