Refactor the parser

package.json

@@ -1,6 +1,6 @@
 {
     "name": "@trojs/formdata-parser",
-    "version": "0.1.1",
+    "version": "0.1.2",
     "description": "Parse the form data",
     "type": "module",
     "main": "src/form-data.js",
@@ -53,4 +53,4 @@
         "globals": "^15.8.0",
         "jscpd": "^4.0.5"
     }
-}
+}

src/form-data.js

@@ -3,6 +3,53 @@
  * @typedef {import('./types.d.ts').FormData} FormData
  */
 
+/**
+ * @param {string} file
+ * @returns {string}
+ */
+const getFileName = (file) => {
+  const fileName = file.split(`filename="`)
+  if (fileName.length > 1) {
+    return fileName[1].split(`"\r\n`)[0]
+  }
+  throw new Error('No file name')
+}
+
+/**
+ * @param {string} file
+ * @returns {string}
+ */
+const getFileData = (file) => {
+  const fileData = file.split(`\r\n\r\n`)
+  if (fileData.length > 1) {
+    return fileData[1].split(`\r\n`)[0]
+  }
+  throw new Error('No file data')
+}
+
+/**
+ * @param {string} file
+ * @returns {string}
+ */
+const getField = (file) => {
+  const fieldName = file.split(`name="`)
+  if (fieldName.length > 1) {
+    return fieldName[1].split(`";`)[0]
+  }
+  throw new Error('No field')
+}
+/**
+ * @param {string} file
+ * @returns {string}
+ */
+const getContentType = (file) => {
+  const contentType = file.split(`Content-Type: `)
+  if (contentType.length > 1) {
+    return contentType[1].split(`\r\n`)[0]
+  }
+  throw new Error('No content type')
+}
+
 /**
  * Parse multipart/form-data
  * @param {string} data
@@ -21,10 +68,10 @@ export default (data, header) => {
       return undefined
     }
     return {
-      fileName: file.split(`filename="`)[1].split(`"\r\n`)[0],
-      fileData: file.split(`\r\n\r\n`)[1].split(`\r\n`)[0],
-      field: file.split(`name="`)[1].split(`";`)[0],
-      contentType: file.split(`Content-Type: `)[1].split(`\r\n`)[0],
+      fileName: getFileName(file),
+      fileData: getFileData(file),
+      field: getField(file),
+      contentType: getContentType(file),
       boundary
     }
   }).filter(file => file !== undefined)