[feat] metrica plugin

src/ts/plugins/metrica.ts

@@ -0,0 +1,68 @@
+
+const convertion:[string,string,number][] = [
+    ['kg', 'lbs', 2.20462],
+    ['m', 'ft', 3.28084],
+    ['cm', 'in', 0.393701],
+    ['mm', 'in', 0.0393701],
+    ['km', 'mi', 0.621371],
+    ['killogram', 'pound', 2.20462],
+    ['meter', 'foot', 3.28084],
+    ['centimeter', 'inch', 0.393701],
+    ['millimeter', 'inch', 0.0393701],
+    ['kilometer', 'mile', 0.621371],
+]
+
+export function metricaPlugin(data:string, toSystem:'metrics'|'imperial'){
+    const c = convertion.sort((a,b) => b[0].length - a[0].length);    
+
+    for(let i=0;i<data.length;i++){
+        function extractNumber(data:string, i:number){
+            let number = '';
+            while(i > 0){
+                i--;
+                if(data[i] === ' ' || data[i] === '\n' || data[i] === '\t' || data[i] === ','){
+                    continue
+                }
+                if(data[i] === '.'){
+                    number = '.' + number;
+                    continue;
+                }
+                if(isNaN(Number(data[i]))){
+                    break;
+                }
+                number = data[i] + number;
+            }
+            i++
+            while(data[i] === ' ' || data[i] === '\n' || data[i] === '\t' || data[i] === ','){
+                i++;
+            }
+            return {
+                number: number === '' ? 0 : Number(number),
+                index: i
+            };
+        }
+
+        let sub = ''
+        let sublen = 0;
+        for(let j=0;j<c.length;j++){
+            const [from, to, ratio] = (toSystem === 'imperial') ? c[j] : [c[j][1], c[j][0], 1/c[j][2]];
+            if(sublen !== from.length){
+                sub = data.substring(i,i+from.length)
+                sublen = from.length;
+            }
+            if(sub === from){
+                const n = extractNumber(data, i);
+                if(n .number !== 0){
+                    const num = (n.number * ratio)
+                    const rto = (num >= 1) ? num.toFixed(0) : num.toFixed(1);
+                    const newData = data.substring(0, n.index) + rto + ' ' + to + data.substring(i+from.length);
+                    const offset = newData.length - data.length;
+                    i += offset;
+                    data = newData;
+                }
+            }
+        }
+
+    }
+    return data
+}