/*
MIT License
Copyright (c) 2021 lalit10
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/
/*
* Background script
* This is always running while the extension is enabled
* Code here is only executed when triggered by user actions
* Or when other code asks to
*/
// Important variables and constants
let _previousData=""; // Last read clipboard data, to avoid having duplicate entries
let _maxListSize = 100; // Maximum size of the list
// Note that, per Chrome limitations, the list cannot be larger than 8 KB
/*
* Custom application context menus
* From https://arndom.hashnode.dev/how-to-add-a-context-menu-to-your-chrome-extension-in-react
* Added so we get actions for storing links and images in the clipboard
*/
chrome.runtime.onInstalled.addListener(() => {
// Create context menu to copy images
chrome.contextMenus.create({
"id": "copyImageClippy", // Unique id for menu
"title": "Copy image to SimplyClip", // What appears in the menu
"contexts": ['image'] // to make this appear only when user selects an image on page
});
// Create context menu to copy links
chrome.contextMenus.create({
"id": "copyLink", // Unique id for menu
"title": "Copy link to SimplyClip", // What appears in the menu
"contexts": ["link"] // to make this appear only when user selects an hyperlink on page
});
});
/**
* Checks if clipboardtext can be added and ads it if so.
* This is the main entrypoint for storing data in clipboard.
* Conditions to add:
* 1. App must be toggled on
* 2. Copied text must be non-empty
* 3. Must be different from last read entry
*
* **Input**
* - Content copied by user, text only.
*
* **Output**
* - None
* - Text is added to the clipboard list if conditions are met
*/
function readClipboardText(clipboardText) {
chrome.storage.sync.get(["apptoggle"],function(result){
if (result.apptoggle == 1) {
console.log(clipboardText)
if(clipboardText.length>0 && clipboardText!==_previousData){
addClipboardList(clipboardText);
_previousData = clipboardText
}
}
// Uncomment for debugging
// else { console.log("Nope, extension is off.") }
})
}
/**
* Adds content to cliboard list.
* Should not be used directly, instead use readClipboardText.
*
* **Input**
* - Content copied by user, text only
*
* **Output**
* - None
* - Text is added to the clipboard list if conditions are met
*/
const addClipboardList = async (clipText)=>{
chrome.storage.sync.get("list", function(clipboard) {
// Create a copy
let {list} = clipboard;
// Uncomment for debugging
// console.log("List is:-", list);
// Sanity check, if undefined make it into a list object
if(typeof list === "undefined")
list = [];
// We remove before adding, so list is always <= _maxListSize
if(list.length === _maxListSize)
list.pop();
if(list.indexOf(clipText)==-1)
list.unshift(clipText)
chrome.storage.sync.set({'list':list}
// Uncomment for debugging
// , status=>console.log("Debug : Clipboard Text pushed to list")
);
})
}
/**
* Gets content the user just copied from the clipboard.
* Creates a mock page to paste clipboard content and get it.
* Created from https://stackoverflow.com/questions/22702446/how-to-get-clipboard-data-in-chrome-extension
* and https://github.com/jeske/BBCodePaste/blob/master/bbcodepaste.js
*
* **Input**
* - None
* - Requires browser clipboard to have something in it
*
* **Output**
* - Text content that the user just copied
*/
function getContentFromClipboard() {
// Get the background page, the html file associated with this script
// Note that it should be blank
// So clear the it just in case
bg = chrome.extension.getBackgroundPage();
bg.document.body.innerHTML= "";
// Add a text area with contentEditable=true, to accept the paste action
// And add to the document
helper = bg.document.createElement("textarea");
helper.style.position = "absolute";
helper.style.border = "none";
document.body.appendChild(helper);
// Focus the browser into the text area
helper.select();
// Trigger the paste action
bg.document.execCommand("Paste");
// Read the clipboard contents from the helperdiv and return
var result = helper.value;
return result;
}
/**
* CURRENTLY UNUSED.
*
* Take and image url and save it on the clipboard.
* This is done by converting it to base 64 data.
*
* **Input**
* - URL, must be pointing to an image resource
*
* **Output**
* - None
* - Image data is converted to base64 and saved to clipboard
*/
function setImageFromLink( url ) {
// Make a fetch request to grab image data
fetch( url )
.then(response => response.blob())
.then(imageBlob => {
// Then create a local URL for that image and print it
var reader = new FileReader();
reader.readAsDataURL(imageBlob);
// When data is fetched, convert it to base 64
// Then save it to clipboard
reader.onloadend = function() {
var base64data = reader.result;
readClipboardText(base64data);
}
});
}
/**
* Create important variables.
* That are saved on Chrome's sync storage.
* List of variables:
* 1. apptoggle: determines if the app captures from clipboard actions
* 2. list: History of items copied from the clipboard
*
*
*
* **Input**
* - None
*
* **Output**
* - None
* - The variables are created on sync storage
*/
function setSyncVariables() {
// For debugging, log the call of the routine
// console.log("Clip installed");
// Enable the extension on every install or reinstall
chrome.storage.sync.set({ apptoggle: 1 });
// Create list variable
// Only on first install or if it is undefined
chrome.storage.sync.get("list", function(list) {
if(typeof list === "undefined")
chrome.storage.sync.set({ list: [] });
})
// For debugging, remove list on every reinstall
// chrome.storage.sync.set({ list: [] });
}
// Run when extension is installed or reloaded.
chrome.runtime.onInstalled.addListener( setSyncVariables )
/**
* When user triggers a copy, capture the content they just copied
* and save it into the clipboard
*
* **Input**
* - None
*
* **Output**
* - None
* - If conditions are met, the text is stored into the clipboard
*/
function onCopyMessage(request, sender, sendResponse) {
if (request.event == "copy") {
readClipboardText( getContentFromClipboard() );
}
}
// Run when a "copy" message is sent.
// This is done when user copies or cuts text from the clipboard.
chrome.runtime.onMessage.addListener(onCopyMessage);
/**
* Push link or image to the clipboard list.
*
* **Input**
* - None
*
* **Output**
* - None
* - If conditions are met, the text is stored into the clipboard
*/
function onContextMenuClick(clickData) {
// For images
if(clickData.menuItemId == "copyImageClippy"){
readClipboardText( clickData.srcUrl );
}
// For links
else if(clickData.menuItemId == "copyLink") {
readClipboardText(clickData.linkUrl);
}
}
// Runs when a context menu item is selected.
chrome.contextMenus.onClicked.addListener( onContextMenuClick )