Enables chart in the app

apps/batchart/app.js

@@ -1,20 +1,100 @@
-// place your const, vars, functions or classes here
+const GraphXZero = 40;
+const GraphYZero = 180;
+const GraphY100 = 80;
+const GraphMarkerOffset = 5;
+const MaxValueCount = 144;
+const GraphXMax = GraphXZero + MaxValueCount;
+var Storage = require("Storage");
 
-function renderBatteryChart(){
-  g.drawString("t", 215, 175);
-  g.drawLine(40,190,40,80);
+function renderCoordinateSystem() {
+  g.setFont("6x8", 1);
+  g.drawString("t", GraphXMax + GraphMarkerOffset, GraphYZero - GraphMarkerOffset);
+  g.drawLine(GraphXZero, GraphYZero + GraphMarkerOffset, GraphXZero, GraphY100);
   
   g.drawString("%", 39, 70);
-  g.drawString("100", 15, 75);
-  g.drawLine(35,80,40,80);
   
-  g.drawString("50", 20,125);
-  g.drawLine(35,130,40,130);
+  g.setFontAlign(1, -1, 0);
+  g.drawString("100", 30, GraphY100 - GraphMarkerOffset);
+  g.drawLine(GraphXZero - GraphMarkerOffset, GraphY100, GraphXZero, GraphY100);
   
-  g.drawString("0", 25, 175);
-  g.drawLine(35,180,210,180);
+  g.drawString("50", 30, GraphYZero - 50 - GraphMarkerOffset);
+  g.drawLine(GraphXZero - GraphMarkerOffset, 130, GraphXZero, 130);
   
-  g.drawString("Chart not yet functional", 60, 125);
+  g.drawString("0", 30, GraphYZero - GraphMarkerOffset);
+  g.drawLine(GraphXZero - GraphMarkerOffset, GraphYZero, GraphXMax, GraphYZero);
+}
+
+function decrementDay(dayToDecrement) {
+  return dayToDecrement === 0 ? 6 : dayToDecrement-1;
+}
+function loadData() {
+  const MaxValueCount = 144;
+  const startingDay = new Date().getDay();
+
+  // Load data for the current day
+  var logFileName = "bclog" + startingDay;
+  
+  var dataLines = loadLinesFromFile(MaxValueCount, logFileName);
+  
+  // Top up to MaxValueCount from previous days as required
+  var previousDay = decrementDay(startingDay);
+  while (dataLines.length < MaxValueCount
+    && previousDay !== startingDay) {
+    
+    var topUpLogFileName = "bclog" + previousDay;
+    var remainingLines = MaxValueCount - dataLines.length;
+    var topUpLines = loadLinesFromFile(remainingLines, topUpLogFileName);
+    dataLines = topUpLines.concat(dataLines);
+    
+    previousDay = decrementDay(previousDay);
+  }
+
+  return dataLines;
+}
+
+function loadLinesFromFile(requestedLineCount, fileName) {
+  var allLines = [];
+  var returnLines = [];
+
+  var readFile = Storage.open(fileName, "r");
+  
+  while ((nextLine = readFile.readLine())) {
+    if(nextLine) {
+      allLines.push(nextLine);
+    }
+  }
+
+  if (allLines.length <= 0) return;
+
+  linesToReadCount = Math.min(requestedLineCount, allLines.length);
+  startingLineIndex = Math.max(0, allLines.length - requestedLineCount - 1);
+
+  for (let i = startingLineIndex; i < linesToReadCount + startingLineIndex; i++) {
+    if(allLines[i]) {
+      returnLines.push(allLines[i]);
+    }
+  }
+  
+  allLines = null;
+  
+  return returnLines;
+}
+
+function renderData(dataArray) {
+  g.setColor(1, 1, 0);
+  for (let i = 0; i < dataArray.length; i++) {
+    const element = dataArray[i];
+    var dataInfo = element.split(",");
+    var batteryPercentage = parseInt(dataInfo[1]);
+
+    g.setPixel(GraphXZero + i, GraphYZero - batteryPercentage);
+  }
+}
+
+function renderBatteryChart() {
+  renderCoordinateSystem();
+  var data = loadData();
+  renderData(data);
 }
 
 // special function to handle display switch on
@@ -22,7 +102,10 @@ Bangle.on('lcdPower', (on) => {
   if (on) {
     // call your app function here
     // If you clear the screen, do Bangle.drawWidgets();
-    renderBatteryChart();
+    //g.clear()
+    Bangle.loadWidgets();
+    Bangle.drawWidgets();
+    //renderBatteryChart();
   }
 });
 

apps/batchart/widget.js

@@ -60,7 +60,6 @@
     }
   }
 
-  // Called by the heart app to reload settings and decide what's
   function reload() {
     WIDGETS["batchart"].width = 24;