From a5b51f34dfd9dce904c4887bc7d3dfd9857c70e1 Mon Sep 17 00:00:00 2001
From: Robin North <robin@robinnorth.co.uk>
Date: Wed, 21 Feb 2018 18:27:26 +0000
Subject: [PATCH] Fix GET form submission

---
 lib/proto/attach-form.js        | 10 +++-----
 lib/send-request.js             | 41 +++++++++++++++++++++++++--------
 lib/util/update-query-string.js | 10 ++++++++
 3 files changed, 45 insertions(+), 16 deletions(-)
 create mode 100644 lib/util/update-query-string.js

diff --git a/lib/proto/attach-form.js b/lib/proto/attach-form.js
index 4f6ed82..43ac1a6 100644
--- a/lib/proto/attach-form.js
+++ b/lib/proto/attach-form.js
@@ -44,23 +44,19 @@ var formAction = function(el, event) {
 
   event.preventDefault()
 
-  var paramObject = []
+  var params = []
   for (var elementKey in el.elements) {
     var element = el.elements[elementKey]
     // jscs:disable disallowImplicitTypeConversion
     if (!!element.name && element.attributes !== undefined && element.tagName.toLowerCase() !== "button") {
       // jscs:enable disallowImplicitTypeConversion
       if ((!element.attributes.type || element.attributes.type.value !== "checkbox" && element.attributes.type.value !== "radio") || element.checked) {
-        paramObject.push({name: encodeURIComponent(element.name), value: encodeURIComponent(element.value)})
+        params.push({name: encodeURIComponent(element.name), value: encodeURIComponent(element.value)})
       }
     }
   }
 
-  // Creating a getString
-  var paramsString = (paramObject.map(function(value) {return value.name + "=" + value.value})).join("&")
-
-  options.requestOptions.requestPayload = paramObject
-  options.requestOptions.requestPayloadString = paramsString
+  options.requestOptions.requestParams = params
 
   el.setAttribute(attrClick, "submit")
 
diff --git a/lib/send-request.js b/lib/send-request.js
index 618f65b..58ce7fd 100644
--- a/lib/send-request.js
+++ b/lib/send-request.js
@@ -1,7 +1,10 @@
+var updateQueryString = require("./util/update-query-string");
+
 module.exports = function(location, options, callback) {
   options = options || {}
-  var requestMethod = options.requestMethod || "GET"
-  var requestPayload = options.requestPayloadString || null
+  var requestMethod = (options.requestMethod || "GET").toUpperCase()
+  var requestParams = options.requestParams || null
+  var requestPayload = null
   var request = new XMLHttpRequest()
 
   request.onreadystatechange = function() {
@@ -24,19 +27,39 @@ module.exports = function(location, options, callback) {
     callback(null, request)
   }
 
-  // Add a timestamp as part of the query string if cache busting is enabled
-  if (this.options.cacheBust) {
-    location += (!/[?&]/.test(location) ? "?" : "&") + new Date().getTime()
+  // Prepare the request payload for forms, if available
+  if (requestParams && requestParams.length) {
+    switch (requestMethod) {
+      case "GET":
+        // Reset query string to avoid an issue with repeat submissions where checkboxes that were
+        // previously checked are incorrectly preserved
+        location = location.split("?")[0]
+
+        // Build new query string
+        requestParams.forEach(function(param) {
+          location = updateQueryString(location, param.name, param.value)
+        });
+        break;
+
+      case "POST":
+        // Build payload string
+        requestPayload = (requestParams.map(function(param) {return param.name + "=" + param.value})).join("&")
+        break;
+    }
   }
 
-  request.open(requestMethod.toUpperCase(), location, true)
+  // Add a timestamp as part of the query string if cache busting is enabled
+  if (this.options.cacheBust) {
+    location = updateQueryString(location, "t", Date.now())
+  }
+
+  request.open(requestMethod, location, true)
   request.timeout = options.timeout
   request.setRequestHeader("X-Requested-With", "XMLHttpRequest")
   request.setRequestHeader("X-PJAX", "true")
 
-  // Add the request payload if available
-  if (options.requestPayloadString !== undefined && options.requestPayloadString !== "") {
-    // Send the proper header information along with the request
+  // Send the proper header information for POST forms
+  if (requestPayload && requestMethod === "POST") {
     request.setRequestHeader("Content-type", "application/x-www-form-urlencoded")
   }
 
diff --git a/lib/util/update-query-string.js b/lib/util/update-query-string.js
new file mode 100644
index 0000000..3635de0
--- /dev/null
+++ b/lib/util/update-query-string.js
@@ -0,0 +1,10 @@
+module.exports = function(uri, key, value) {
+  var re = new RegExp("([?&])" + key + "=.*?(&|$)", "i")
+  var separator = uri.indexOf("?") !== -1 ? "&" : "?"
+  if (uri.match(re)) {
+    return uri.replace(re, "$1" + key + "=" + value + "$2")
+  }
+  else {
+    return uri + separator + key + "=" + value
+  }
+}