import SwiftUI
import AppKit
import SwiftTerm

/// Full terminal emulator view (SwiftTerm): cursor addressing, colors,
/// scrollback, selection, and full-screen apps like vim/htop.
/// Keyboard goes straight to the pty (Tab completion, arrows, Ctrl+C, Esc);
/// pty output is fed in via PTYSession.onData. Dracula themed.
struct SwiftTermView: NSViewRepresentable {
    @ObservedObject var term: PTYSession

    func makeCoordinator() -> Coordinator {
        Coordinator(term: term)
    }

    func makeNSView(context: Context) -> TerminalView {
        let view = TerminalView(frame: .zero,
                                   font: .monospacedSystemFont(ofSize: 13, weight: .regular))
        view.terminalDelegate = context.coordinator
        view.nativeForegroundColor = Dracula.nsColor(for: nil)
        view.nativeBackgroundColor = Dracula.nsBackground
        let palette = Dracula.ansiPalette
        if palette.count == 16 {
            view.installColors(palette)
        }
        context.coordinator.view = view
        term.onData = { [weak view] data in
            let bytes = Array(data)
            DispatchQueue.main.async {
                view?.feed(byteArray: bytes[...])
            }
        }
        // Sync current size once the view exists (later resizes via delegate).
        DispatchQueue.main.async {
            term.setWinsize(cols: view.terminal.cols, rows: view.terminal.rows)
        }
        return view
    }

    func updateNSView(_ view: TerminalView, context: Context) {
        context.coordinator.term = term
    }

    final class Coordinator: NSObject, TerminalViewDelegate {
        var term: PTYSession?
        weak var view: TerminalView?

        init(term: PTYSession) {
            self.term = term
        }

        func send(source: TerminalView, data: ArraySlice<UInt8>) {
            term?.sendBytes(Data(data))
        }

        func sizeChanged(source: TerminalView, newCols: Int, newRows: Int) {
            term?.setWinsize(cols: newCols, rows: newRows)
        }

        func setTerminalTitle(source: TerminalView, title: String) {}
        func hostCurrentDirectoryUpdate(source: TerminalView, directory: String?) {}
        func scrolled(source: TerminalView, position: Double) {}
        func rangeChanged(source: TerminalView, startY: Int, endY: Int) {}
    }
}