import SwiftUI

struct PersonsView: View {
    @EnvironmentObject var store: Store
    @State private var newName = ""
    @FocusState private var newFocused: Bool

    private let nameWidth: CGFloat = 220
    private let genderWidth: CGFloat = 120
    private let noteWidth: CGFloat = 180
    private let checkWidth: CGFloat = 32

    var body: some View {
        VStack(alignment: .leading, spacing: 0) {
            HStack(spacing: 10) {
                TextField("Name der neuen Person", text: $newName)
                    .textFieldStyle(.roundedBorder)
                    .frame(width: 260)
                    .focused($newFocused)
                    .onSubmit(add)
                Button("Hinzufügen", action: add).buttonStyle(.borderedProminent)
                    .disabled(newName.trimmingCharacters(in: .whitespaces).isEmpty)
                Text("Häkchen = darf diese Aufgabe übernehmen. Wer mindestens eine Diener-Aufgabe hat, erscheint oben in der Übersicht, wer eine Schulungsaufgabe hat, unten.")
                    .font(.caption).foregroundStyle(Theme.muted)
                    .fixedSize(horizontal: false, vertical: true)
            }
            .padding(16)

            ScrollView([.horizontal, .vertical]) {
                VStack(alignment: .leading, spacing: 0) {
                    headerRow
                    ForEach(store.personsSorted) { p in
                        if let binding = store.binding(person: p.id) {
                            PersonRow(person: binding, widths: (nameWidth, genderWidth, noteWidth, checkWidth))
                        }
                    }
                }
                .padding([.horizontal, .bottom], 16)
            }
        }
    }

    private var headerRow: some View {
        HStack(alignment: .bottom, spacing: 0) {
            Text("Name").frame(width: nameWidth, alignment: .leading).padding(.leading, 4)
            Text("Bruder/Schwester").frame(width: genderWidth, alignment: .leading)
            Text("Notiz").frame(width: noteWidth, alignment: .leading)
            ForEach(store.db.tasks) { t in
                Text(t.name)
                    .lineLimit(1)
                    .fixedSize()
                    .rotationEffect(.degrees(-90))
                    .frame(width: checkWidth, height: 170, alignment: .center)
                    .background(Theme.soft(for: t.group))
                    .help(t.name)
            }
            Spacer().frame(width: 80)
        }
        .font(.caption.weight(.semibold))
        .foregroundStyle(Theme.muted)
        .padding(.bottom, 6)
        .overlay(alignment: .bottom) { Rectangle().fill(Theme.line).frame(height: 1) }
    }

    private func add() {
        if store.addPerson(named: newName) { newName = "" } else { NSSound.beep() }
        newFocused = true
    }
}

struct PersonRow: View {
    @Binding var person: Person
    let widths: (name: CGFloat, gender: CGFloat, note: CGFloat, check: CGFloat)
    @EnvironmentObject var store: Store
    @State private var name = ""
    @FocusState private var focused: Bool

    var body: some View {
        HStack(spacing: 0) {
            TextField("Name", text: $name)
                .textFieldStyle(.roundedBorder)
                .frame(width: widths.name - 12)
                .padding(.trailing, 12)
                .onAppear { name = person.name }
                .focused($focused)
                .onSubmit(commitName)
                .onChange(of: focused) { _, now in if !now { commitName() } }
                .onDisappear(perform: commitName)
            Picker("", selection: $person.gender) {
                Text("–").tag("")
                Text("Bruder").tag("Bruder")
                Text("Schwester").tag("Schwester")
            }
            .labelsHidden()
            .frame(width: widths.gender - 12)
            .padding(.trailing, 12)
            TextField("", text: $person.note)
                .textFieldStyle(.roundedBorder)
                .frame(width: widths.note - 12)
                .padding(.trailing, 12)
            ForEach(store.db.tasks) { t in
                Toggle("", isOn: Binding(
                    get: { person.tasks.contains(t.id) },
                    set: { on in
                        if on { if !person.tasks.contains(t.id) { person.tasks.append(t.id) } }
                        else { person.tasks.removeAll { $0 == t.id } }
                    }))
                .toggleStyle(.checkbox)
                .labelsHidden()
                .frame(width: widths.check)
                .help(t.name)
            }
            Button("Löschen", role: .destructive, action: delete)
                .buttonStyle(.link)
                .foregroundStyle(Theme.bengara)
                .frame(width: 80)
        }
        .padding(.vertical, 5)
        .overlay(alignment: .bottom) { Rectangle().fill(Theme.line).frame(height: 1) }
    }

    private func commitName() {
        let n = name.trimmingCharacters(in: .whitespaces)
        guard n != person.name else { return }
        if n.isEmpty || store.db.persons.contains(where: { $0.id != person.id && $0.name.lowercased() == n.lowercased() }) {
            NSSound.beep(); name = person.name; return
        }
        person.name = n
    }

    private func delete() {
        let count = store.entryCount(person: person.id)
        let alert = NSAlert()
        alert.messageText = "\(person.name) löschen?"
        alert.informativeText = count > 0
            ? "\(count) Einträge im Verlauf gehören zu dieser Person und werden ebenfalls gelöscht."
            : "Die Person hat noch keine Einträge im Verlauf."
        alert.addButton(withTitle: "Löschen").hasDestructiveAction = true
        alert.addButton(withTitle: "Abbrechen")
        guard alert.runModal() == .alertFirstButtonReturn else { return }
        store.deletePerson(person.id)
    }
}