import AppKit
import SstData
import SstUI
import SwiftUI

struct NoteView: View {
    @EnvironmentObject private var model: AppModel
    @ObservedObject var note: NoteStore
    @State private var confirmingClear = false

    private var editedEntry: HistoryEntry? {
        model.editingEntryID.flatMap { model.historyList.entry(id: $0) }
    }

    /// The note, or the transcript being edited.
    private var text: Binding<String> {
        if let entry = editedEntry {
            return Binding(
                get: { model.historyList.entry(id: entry.id)?.finalText ?? "" },
                set: { model.historyList.updateText(id: entry.id, to: $0) })
        }
        return $note.text
    }

    var body: some View {
        VStack(spacing: Layout.panelGap) {
            header
            ZStack {
                PaperBackground()
                if SnapshotMode.isActive {
                    // ImageRenderer cannot draw an NSView; the snapshot shows the text instead.
                    Text(text.wrappedValue)
                        .textStyle(Typography.reading)
                        .foregroundStyle(Palette.inkPrimary)
                        .padding(Space.s5)
                        .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .topLeading)
                } else {
                    NoteEditor(text: text, isEditable: editedEntry != nil || !note.isReadOnly)
                        .id(editedEntry?.id)
                }
            }
            footer
        }
        .confirmationDialog(Strings.clearNoteConfirm, isPresented: $confirmingClear) {
            Button(Strings.clear, role: .destructive) { note.text = "" }
        }
        .onChange(of: model.section) { _, new in
            if new != .note { model.editingEntryID = nil }
        }
    }

    private var header: some View {
        HStack(spacing: Space.s4) {
            if let entry = editedEntry {
                SilkLabel("\(Strings.transcript) · \(entry.date.formatted(Date.FormatStyle().hour().minute().second().locale(Locale(identifier: "nl_NL"))))")
            } else {
                SilkLabel(Strings.note)
            }
            Spacer()
            Text(Strings.characters(text.wrappedValue.count))
                .textStyle(Typography.counterSmall)
                .foregroundStyle(Palette.inkSecondary)
            Button(Strings.copy) {
                NSPasteboard.general.clearContents()
                NSPasteboard.general.setString(text.wrappedValue, forType: .string)
            }
            .buttonStyle(KeyButtonStyle())
            .disabled(text.wrappedValue.isEmpty)
            if editedEntry != nil {
                Button(Strings.done) {
                    model.editingEntryID = nil
                    model.section = .transcripts
                }
                .buttonStyle(KeyButtonStyle(kind: .record))
            } else {
                Button(Strings.clear) { confirmingClear = true }
                    .buttonStyle(KeyButtonStyle())
                    .disabled(note.text.isEmpty)
            }
        }
    }

    private var footer: some View {
        Text(footerText)
            .textStyle(Typography.label)
            .foregroundStyle(Palette.inkTertiary)
            .frame(maxWidth: .infinity, alignment: .leading)
    }

    private var footerText: String {
        if editedEntry != nil { return Strings.editingTranscriptHint }
        return note.isReadOnly ? Strings.noteUnreadable : Strings.noteHint(model.hotkeyBinding.displayName)
    }
}