实现多开并且串口数据处理后传递至渲染端

src/main/api/NMEAHandler.js

@@ -0,0 +1,89 @@
+import nmea from 'nmea'
+
+let events         = {}
+const on           = (eventName, callback) => {
+  if (!(eventName in events)) {
+    events[eventName] = []
+  }
+
+  events[eventName].push(callback)
+}
+
+const emit         = (eventName, ...args) => {
+  if (!(eventName in events)) {
+    return
+  }
+  
+  const cbs  = events[eventName]
+
+  cbs.forEach(cb => {
+    cb.call(this, ...args)
+  });
+}
+
+const handle       = (value) => {
+  if (value.length <= 0) return
+
+  emit('received', value)
+
+  const strArr = value.split('\r\n')
+  for (let i = 0; i < strArr.length; i++) {
+    const element = strArr[i];
+    doHandle(element)
+  }
+  
+  emit('handled', nmeaObj)
+  nmeaObj = resetNMEAObj()
+}
+
+const doHandle     = (value) => {
+  if (!verify(value)) {
+    return
+  }
+
+  const result = nmea.parse(value)
+  switch (result.sentence) {
+    case 'RMC':
+      nmeaObj.RMC = result
+      break;
+    case 'GGA':
+      nmeaObj.GGA = result
+      break;
+    case 'GSA':
+      if (result.talker_id === 'BD') nmeaObj.GSA.push(result)
+      break;
+    case 'GSV':
+      if (result.talker_id === 'BD') nmeaObj.GSV.push(result)
+      break;
+    case 'TXT':
+      break;
+  }
+}
+
+const verify       = (value) => {
+  if (!value) {
+    return false
+  }
+
+  const dollar_index = value.indexOf('$')
+  const star_index   = value.indexOf('*')
+  if (value.indexOf('$') !== 0 || star_index <= dollar_index) {
+    return false
+  }
+  
+  const [sentence, checksum, ] = value.split('*')
+  return nmea.Helpers.verifyChecksum(sentence, checksum)
+}
+
+const resetNMEAObj = () => {
+  return {
+    'RMC': null,
+    'GGA': null,
+    'GSA': [],
+    'GSV': []
+  }
+}
+
+let nmeaObj        = resetNMEAObj()
+
+module.exports = { on, handle }