nowser/lib/component/webview/webview_linux_component.dart

import 'dart:convert';

import 'package:flutter/material.dart';
import 'package:nostr_sdk/event.dart';
import 'package:nostr_sdk/utils/string_util.dart';
import 'package:nowser/component/webview/web_info.dart';
import 'package:nowser/const/app_type.dart';
import 'package:nowser/const/auth_type.dart';
import 'package:nowser/main.dart';
import 'package:nowser/provider/permission_check_mixin.dart';
import 'package:webview_cef/webview_cef.dart';
import 'package:webview_cef/src/webview_inject_user_script.dart';

import '../../data/app.dart';

class WebViewLinuxComponent extends StatefulWidget {
  WebInfo webInfo;

  Function(WebInfo, WebViewController) onWebViewCreated;

  Function(WebInfo, WebViewController, String?) onTitleChanged;

  Function(WebInfo, WebViewController, String?) onUrlChanged;

  Function(WebInfo, WebViewController) onLoadStop;

  WebViewLinuxComponent(
    this.webInfo,
    this.onWebViewCreated,
    this.onTitleChanged,
    this.onUrlChanged,
    this.onLoadStop,
  );

  @override
  State<StatefulWidget> createState() {
    return _WebViewLinuxComponent();
  }
}

class _WebViewLinuxComponent extends State<WebViewLinuxComponent>
    with PermissionCheckMixin {
  late WebViewController controller;

  double progress = 0;

  Set<JavascriptChannel> javascriptChannels = {};

  InjectUserScripts injectScript = InjectUserScripts();

  String url = "";

  String title = "";

  @override
  void initState() {
    super.initState();

    initInjectScript();
    initJSHandle();

    controller = WebviewManager().createWebView(
        loading: const Text("Loading"),
        injectUserScripts: injectScript);
    controller.setWebviewListener(WebviewEventsListener(
      onTitleChanged: (title) {
        title = title;
        widget.onTitleChanged(widget.webInfo, controller, title);
      },
      onUrlChanged: (url) {
        url = url;
        widget.onUrlChanged(widget.webInfo, controller, url);
      },
      onConsoleMessage: (int level, String message, String source, int line) {
        print("$level $source $line $message");
      },
      // onLoadStart: (controller, url) {
      // },
      onLoadEnd: (controller, url) {
        widget.onLoadStop(widget.webInfo, controller);
      },
    ));

    controller.initialize(widget.webInfo.url).then((v) {
      controller.setJavaScriptChannels(javascriptChannels);
      setState(() {
        inited = true;
      });

      // controller.openDevTools();
    });
  }

  var inited = false;

  @override
  Widget build(BuildContext context) {
    return Container(
      child: inited ? controller.webviewWidget : controller.loadingWidget,
    );
  }

  Future<void> nip07Reject(String resultId, String contnet) async {
    var script = "window.nostr.reject(\"$resultId\", \"${contnet}\");";
    await controller.executeJavaScript(script);
  }

  void initJSHandle() {
    javascriptChannels.add(JavascriptChannel(name: "NowserJSgetPublicKey",
      onMessageReceived: (javascriptMessage) async {
      var jsMsg = javascriptMessage.message;
        print("NowserJSgetPublicKey $jsMsg");
        var jsonObj = jsonDecode(jsMsg);
        var resultId = jsonObj["resultId"];

        String? code = await getCode();
        if (code == null) {
          return;
        }

        checkPermission(context, AppType.WEB, code, AuthType.GET_PUBLIC_KEY,
            (app) {
          nip07Reject(resultId, "Forbid");
        }, (app, signer) {
          print("confirm get pubkey");
          var pubkey = app.pubkey;
          var script = "window.nostr.callback(\"$resultId\", \"$pubkey\");";
          controller.executeJavaScript(script);
        });
      },)
    );
    javascriptChannels.add(JavascriptChannel(name: "NowserJSsignEvent",
      onMessageReceived: (javascriptMessage) async {
      var jsMsg = javascriptMessage.message;
        print("NowserJSsignEvent $jsMsg");
        var jsonObj = jsonDecode(jsMsg);
        var resultId = jsonObj["resultId"];
        var content = jsonObj["msg"];

        String? code = await getCode();
        if (code == null) {
          return;
        }

        try {
          var eventObj = jsonDecode(content);
          var eventKind = eventObj["kind"];
          if (eventKind is int) {
            checkPermission(context, AppType.WEB, code, AuthType.SIGN_EVENT,
                eventKind: eventKind, authDetail: content, (app) {
              nip07Reject(resultId, "Forbid");
            }, (app, signer) async {
              var tags = eventObj["tags"];
              Event? event = Event(app.pubkey!, eventObj["kind"], tags ?? [],
                  eventObj["content"],
                  createdAt: eventObj["created_at"]);
              event = await signer.signEvent(event);
              if (event == null) {
                return;
              }

              var eventResultStr = jsonEncode(event.toJson());
              // TODO this method to handle " may be error
              eventResultStr = eventResultStr.replaceAll("\"", "\\\"");
              var script =
                  "window.nostr.callback(\"$resultId\", JSON.parse(\"$eventResultStr\"));";
              controller.executeJavaScript(script);
            });
          }
        } catch (e) {
          nip07Reject(resultId, "Sign fail");
        }
      },)
    );
    javascriptChannels.add(JavascriptChannel(name: "NowserJSgetRelays",
      onMessageReceived: (javascriptMessage) async {
      var jsMsg = javascriptMessage.message;
        print("NowserJSgetRelays $jsMsg");
        var jsonObj = jsonDecode(jsMsg);
        var resultId = jsonObj["resultId"];

        String? code = await getCode();
        if (code == null) {
          return;
        }

        checkPermission(context, AppType.WEB, code, AuthType.GET_RELAYS, (app) {
          nip07Reject(resultId, "Forbid");
        }, (app, signer) {
          // TODO handle getRelays
          // var app = appProvider.getApp(AppType.WEB, code);
          // if (app != null) {
          //   var relayMaps = {};
          //   var relayAddrs = relayProvider.relayAddrs;
          //   for (var relayAddr in relayAddrs) {
          //     relayMaps[relayAddr] = {"read": true, "write": true};
          //   }
          //   var resultStr = jsonEncode(relayMaps);
          //   resultStr = resultStr.replaceAll("\"", "\\\"");
          //   var script =
          //       "window.nostr.callback(\"$resultId\", JSON.parse(\"$resultStr\"));";
          //   webViewController!.evaluateJavascript(source: script);
          // }
        });
      },)
    );
    javascriptChannels.add(JavascriptChannel(name: "NowserJSnip04encrypt",
      onMessageReceived: (javascriptMessage) async {
      var jsMsg = javascriptMessage.message;
        print("NowserJSnip04encrypt $jsMsg");
        var jsonObj = jsonDecode(jsMsg);
        var resultId = jsonObj["resultId"];
        var msg = jsonObj["msg"];
        if (msg != null && msg is Map) {
          var pubkey = msg["pubkey"];
          var plaintext = msg["plaintext"];

          String? code = await getCode();
          if (code == null) {
            return;
          }

          checkPermission(context, AppType.WEB, code, AuthType.NIP04_ENCRYPT,
              (app) {
            nip07Reject(resultId, "Forbid");
          }, (app, signer) async {
            var resultStr = await signer.encrypt(pubkey, plaintext);
            if (StringUtil.isBlank(resultStr)) {
              return;
            }
            var script =
                "window.nostr.callback(\"$resultId\", \"$resultStr\");";
            controller.executeJavaScript(script);
          });
        }
      },)
    );
    javascriptChannels.add(JavascriptChannel(name: "NowserJSnip04decrypt",
      onMessageReceived: (javascriptMessage) async {
      var jsMsg = javascriptMessage.message;
        print("NowserJSnip04decrypt $jsMsg");
        var jsonObj = jsonDecode(jsMsg);
        var resultId = jsonObj["resultId"];
        var msg = jsonObj["msg"];
        if (msg != null && msg is Map) {
          var pubkey = msg["pubkey"];
          var ciphertext = msg["ciphertext"];

          String? code = await getCode();
          if (code == null) {
            return;
          }

          checkPermission(context, AppType.WEB, code, AuthType.NIP04_DECRYPT,
              (app) {
            nip07Reject(resultId, "Forbid");
          }, (app, signer) async {
            var app = appProvider.getApp(AppType.WEB, code);
            if (app != null) {
              var resultStr = await signer.decrypt(pubkey, ciphertext);
              if (StringUtil.isBlank(resultStr)) {
                return;
              }
              var script =
                  "window.nostr.callback(\"$resultId\", \"$resultStr\");";
              controller.executeJavaScript(script);
            }
          });
        }
      },)
    );
    javascriptChannels.add(JavascriptChannel(name: "NowserJSnip44encrypt",
      onMessageReceived: (javascriptMessage) async {
      var jsMsg = javascriptMessage.message;
        print("NowserJSnip44encrypt $jsMsg");
        var jsonObj = jsonDecode(jsMsg);
        var resultId = jsonObj["resultId"];
        var msg = jsonObj["msg"];
        if (msg != null && msg is Map) {
          var pubkey = msg["pubkey"];
          var plaintext = msg["plaintext"];

          String? code = await getCode();
          if (code == null) {
            return;
          }

          checkPermission(context, AppType.WEB, code, AuthType.NIP44_ENCRYPT,
              (app) {
            nip07Reject(resultId, "Forbid");
          }, (app, signer) async {
            var resultStr = await signer.nip44Encrypt(pubkey, plaintext);
            if (StringUtil.isBlank(resultStr)) {
              return;
            }
            var script =
                "window.nostr.callback(\"$resultId\", \"$resultStr\");";
            controller.executeJavaScript(script);
          });
        }
      },)
    );
    javascriptChannels.add(JavascriptChannel(name: "NowserJSnip44decrypt",
      onMessageReceived: (javascriptMessage) async {
      var jsMsg = javascriptMessage.message;
        print("NowserJSnip44decrypt $jsMsg");
        var jsonObj = jsonDecode(jsMsg);
        var resultId = jsonObj["resultId"];
        var msg = jsonObj["msg"];
        if (msg != null && msg is Map) {
          var pubkey = msg["pubkey"];
          var ciphertext = msg["ciphertext"];

          String? code = await getCode();
          if (code == null) {
            return;
          }

          checkPermission(context, AppType.WEB, code, AuthType.NIP44_DECRYPT,
              (app) {
            nip07Reject(resultId, "Forbid");
          }, (app, signer) async {
            var resultStr = await signer.nip44Decrypt(pubkey, ciphertext);
            if (StringUtil.isBlank(resultStr)) {
              return;
            }
            var script =
                "window.nostr.callback(\"$resultId\", \"$resultStr\");";
            controller.executeJavaScript(script);
          });
        }
      },)
    );
  }

  void initInjectScript() {
    injectScript.add(UserScript("""
window.nostr = {
_call(channel, message) {
    return new Promise((resolve, reject) => {
        var resultId = "callbackResult_" + Math.floor(Math.random() * 100000000);
        var arg = {"resultId": resultId};
        if (message) {
            arg["msg"] = message;
        }
        // var argStr = JSON.stringify(arg);
        // window.flutter_inappwebview
        //               .callHandler(channel, argStr);
        channel(arg);
        window.nostr._requests[resultId] = {resolve, reject}
    });
},
_requests: {},
callback(resultId, message) {
    window.nostr._requests[resultId].resolve(message);
},
reject(resultId, message) {
    window.nostr._requests[resultId].reject(message);
},
async getPublicKey() {
    return window.nostr._call(NowserJSgetPublicKey);
},
async signEvent(event) {
    return window.nostr._call(NowserJSsignEvent, JSON.stringify(event));
},
async getRelays() {
    return window.nostr._call(NowserJSgetRelays);
},
nip04: {
  async encrypt(pubkey, plaintext) {
    return window.nostr._call(NowserJSnip04encrypt, {"pubkey": pubkey, "plaintext": plaintext});
  },
  async decrypt(pubkey, ciphertext) {
      return window.nostr._call(NowserJSnip04decrypt, {"pubkey": pubkey, "ciphertext": ciphertext});
  },
},
nip44: {
  async encrypt(pubkey, plaintext) {
    return window.nostr._call(NowserJSnip44encrypt, {"pubkey": pubkey, "plaintext": plaintext});
  },
  async decrypt(pubkey, ciphertext) {
      return window.nostr._call(NowserJSnip44decrypt, {"pubkey": pubkey, "ciphertext": ciphertext});
  },
},
};
""", ScriptInjectTime.LOAD_START));
// injectScript.add(UserScript("console.log(window.nostr);", ScriptInjectTime.LOAD_END));
  }

  Future<String?> getCode() async {
    if (StringUtil.isBlank(url)) {
      url = widget.webInfo.url;
    }

    if (StringUtil.isNotBlank(url)) {
      var uri = Uri.parse(url);
      return uri.host;
    }

    return null;
  }

  @override
  Future<App> getApp(int appType, String code) async {
    String? name = title;
    String? image;
    // var favicons = await webViewController!.getFavicons();
    // if (favicons.isNotEmpty) {
    //   image = favicons.first.url.toString();
    // }
    return App(appType: appType, code: code, name: name, image: image);
  }

  @override
  void dispose() {
    super.dispose();
    controller.dispose();
  }

}