import {WebView} from 'react-native-webview';
import {useRef} from 'react';
const address = '<personal address>';
const injectedJavaScript = `
    window.ethereum = {};
    window.ethereum.isMetaMask = true;
    window.ethereum.isConnected = function() {
      console.log('-----------连接成功后调用---------')
      return true
    };
    window.ethereum.wallet = {};
    window.ethereum.wallet.address = '${address}';
    window.ethereum.selectedAddress = '${address}';
    window.ethereum.request = function(args = {}) {
      console.log('---------Dapp交互触发该事件-----------', args)
      const { method, params } = args
      return window.ethereum.send(method, params)
    };
    window.ethereum.send = function(method, params) {
      console.log('---------send-----------', method, params)
      return new Promise(function(resolve, reject) {
        window.ReactNativeWebView.postMessage(JSON.stringify({
            type: 'bsc',
            payload: {
                method: method,
                params: params,
            }
        }));
        document.addEventListener("message", function(event) {
          /**
          * wallet端主动调用postMessage触发该事件
          * 将webviewRef.current.postMessage回调的event.data作为Promise的值返回
          */
          const data = JSON.parse(event.data) || {}
          if (data.type === 'ethereum' && data.payload.id === method) {
              if (data.payload.error) {
                  reject(data.payload.error);
              } else {
                  resolve(data.payload.result);
              }
          }
        }, { once: true });
      });
    };
`;

const BrowserTab = function () {
  const webviewRef = useRef(null);
  const handleWebViewMessage = async function (event: any) {
    /**
    * Dapp端交互调用window.ethereum.request时触发
    * 根据window.ReactNativeWebView.postMessage传递的不同参数，返回对应的结果
    */
    const {data} = event.nativeEvent;
    const {type, payload = {}} = JSON.parse(data) || {};
    const {method} = payload;
    console.log(webviewRef.current);
    if (webviewRef.current) {
      method === 'eth_requestAccounts' &&
        webviewRef.current.postMessage(
          JSON.stringify({
            type: 'ethereum',
            payload: {
              id: 'eth_requestAccounts',
              result: [address],
            },
          }),
          '*',
        );
      method === 'eth_chainId' &&
        webviewRef.current.postMessage(
          JSON.stringify({
            type: 'ethereum',
            payload: {
              id: 'eth_chainId',
              result: 5,
            },
          }),
          '*',
        );
    }
  };
  return (
    <WebView
      ref={webviewRef}
      source={{uri: 'https://app.uniswap.org/'}}
      style={{flex: 1}}
      javaScriptEnabled={true}
      onMessage={handleWebViewMessage}
      injectedJavaScriptBeforeContentLoaded={injectedJavaScript}
    />
  );
};

export default BrowserTab;