Added a function to calculate math on notes

client/src/components/NoteInputPanel.vue

@@ -158,12 +158,18 @@
 							Uncheck all Checked items
 						</div>
 					</div>
-					<div class="sixteen wide column">
+					<div class="eight wide column">
 						<div class="ui labeled icon fluid basic button" v-on:click="undoCustom">
 							<i class="undo icon"></i>
 							Undo last change
 						</div>
 					</div>
+					<div class="eight wide column">
+						<div class="ui labeled icon fluid basic button" v-on:click="calculateMath" data-tooltip="Calculates algebra before '='">
+							<i class="calculator icon"></i>
+							Simple Math
+						</div>
+					</div>
 					<div class="sixteen wide column" v-if="rawTextId > 0">
 						<share-note-component 
 							:note-id="noteid"
@@ -561,6 +567,57 @@
 					}
 				})
 			},
+			calculateMath(){
+				//
+				// Find math in note and calculate the outcome
+				//
+
+				//Close menu if user is on mobile, then sort list
+				if(this.$store.getters.getIsUserOnMobile){
+					this.showNoteOptions = false
+				}
+
+				//Fetch the container
+				let container = document.getElementById('squire-id')
+
+				// simple function that trys to evaluate javascript
+				const shittyMath = (string) => {
+					try {
+						return Function('"use strict"; return (' + string + ')')();
+					} catch (error) {
+						console.log('Math Error: ', string)
+						return null
+					}
+				}
+
+				//Go through each item, on first level, look for Unordered Lists
+				container.childNodes.forEach( (node) => {
+
+					const line = node.innerText.trim()
+
+					// = sign exists and its the last character in the string
+					let equalLocation = line.indexOf('=')
+					if(equalLocation != -1 && (line.length-1) == equalLocation ){
+
+						//Pull out everything before the formula and try to evaluate it
+						const formula = line.split('=').shift()
+						const output = shittyMath(formula)
+
+						//If its a number and didn't throw an error, update the line
+						if(!isNaN(output) && output != null){
+
+							//Since there is HTML in the line, splice in the number after the = sign
+							let newLine = node.innerHTML.slice(0, equalLocation+1).trim()
+							newLine += ` ${output}`
+							newLine += node.innerHTML.slice(equalLocation+1).trim()
+
+							//Slam in that new HTML with the output
+							node.innerHTML = newLine
+						}
+					}
+					
+				})
+			},
 			setText(inText){
 
 				this.editor.setHTML(inText)