// ignore_for_file: avoid_web_libraries_in_flutter

import "dart:js_interop";
import "dart:js_interop_unsafe";

import "package:flutter/widgets.dart";

// EyeDropper is a chromium-only api at the time of writing (no firefox, no
// safari), hence the feature check rather than just assuming its there on web.
// https://developer.mozilla.org/en-US/docs/Web/API/EyeDropper

@JS("EyeDropper")
extension type _EyeDropper._(JSObject _) implements JSObject {
  external _EyeDropper();

  external JSPromise<_EyeDropperResult> open();
}

extension type _EyeDropperResult._(JSObject _) implements JSObject {
  external String get sRGBHex;
}

Future<bool> nativeEyedropperAvailable() async =>
    globalContext.has("EyeDropper");

Future<Color?> pickNativeScreenColor() async {
  try {
    final result = await _EyeDropper().open().toDart;
    return _parseHex(result.sRGBHex);
  } catch (error, stack) {
    // cancelling with escape rejects the promise with an AbortError, so this
    // path is completely normal - still worth a line in the console though.
    debugPrint("eyedropper: web pick ended without a colour: $error\n$stack");
    return null;
  }
}

Color? _parseHex(String value) {
  final hex = value.replaceAll("#", "");
  if (hex.length != 6) {
    debugPrint("eyedropper: unexpected sRGBHex \"$value\"");
    return null;
  }
  final parsed = int.tryParse(hex, radix: 16);
  if (parsed == null) {
    debugPrint("eyedropper: could not parse sRGBHex \"$value\"");
    return null;
  }
  return Color(0xFF000000 | parsed);
}