Dark to light theme plugin development

Hi,
I am trying to write a simple plugin to switch theme from light mode to dark mode.

I got a sample project from here. GitHub - destefanis/auto-theme: A figma plugin for automatically theming your designs.

I want to create a very simple proof of concept project having a single rectangle with light and dark theme something as below

From Figma plugin development tutorial, I created the plugin with UI, removed the rectangle creating default code, started using the code from this github project. I started copying from initial commit of this github project to mine. But I don’t know how to test in the sample Figma project I created. I kept continuing use the github project into my project till I found react framework use in that repository. I don’t want react so I am stuck there.

Right now, I have a Figma project with a basic frame/rectangle/text and a running plugin where code.ts is as below.

Figma.showUI(html, {width: 380, height: 350});

const themeMapping = {
// Headings
‘5c1691cbeaaf4270107d34f1a12f02fdd04afa02’: {
name: ‘Dark / Header / Primary (White)’,
mapsToName: “Light / Header / Primary (900)”,
mapsToKey: ‘b19a14675b8adeb1528ab5f84e57b2eeed10d46c’,
},
‘bc090cb3b1c7313ae276acbd791b5b87b478ec59’: {
name: “Dark / Header / Secondary (300)”,
mapsToName: “Light / Header / Secondary (600)”,
mapsToKey: “608f2ea1aa64ff7f202e8c22cc4147a02be9d85b”,
},
// Text
“5c77a96137b698b5575557c069cabd6877d66e1e”: {
name: ‘Dark / Text / Normal (200)’,
mapsToName: “Light / Text / Normal (700)”,
mapsToKey: “546c7d46e754ac2b23b338783d72f206b77b6436”,
},
‘5d84ad92f3ad152f196e2093a3c0542a08dfba11’: {
name: “Dark / Text / Muted (400)”,
mapsToName: “Light / Text / Muted (500)”,
mapsToKey: “7d8703ec132ddaf6968f6d190d1e80031c559d7c”,
},
‘bf03232753079bdd5bec6c55343b659876b5283f’: {
name: “Dark / Text / Link”,
mapsToName: “Light / Text / Link”,
mapsToKey: “64d3058dd508a4985670b2d19418a06a3503c9c2”,
},
// Interactive Text & Icons
‘287463bade90c1eed5ea4cb0b5d63794daa8aec2’: {
name: “Dark / Interactive Text & Icons / Normal (300)”,
mapsToName: “Light / Interactive Text & Icons / Normal (600)”,
mapsToKey: “9c23a031773711e026394f4354661c37ee5b4682”,
},
‘502dcdf04992818dcbaed125ad711b446dee4c68’: {
name: “Dark / Interactive Text & Icons / Hover (200)”,
mapsToName: “Light / Interactive Text & Icons / Hover (700)”,
mapsToKey: “e9542e95adf3bbe74286c2cf279fee64f7ba3279”,
},
‘3eddc15e90bbd7064aea7cc13dc13e23a712f0b0’: {
name: “Dark / Interactive Text & Icons / Active (White)”,
mapsToName: “Light / Interactive Text & Icons / Active (900)”,
mapsToKey: “620c98e8f9255a6107dee91745669e5b702b413c”,
},
‘fa698aa2a724522a7c29efb0a662aec75a1be5a1’: {
name: “Dark / Interactive Text & Icons / Muted (500)”,
mapsToName: “Light / Interactive Text & Icons / Muted (300)”,
mapsToKey: “9328cd78a39149b070d68f98d9fe4df7a92bf67d”,
},
// Backgrounds
‘4b93d40f61be15e255e87948a715521c3ae957e6’: {
name: ‘Dark / Background / Primary (600)’,
mapsToName: “Light / Background / Primary (White)”,
mapsToKey: “2449a2983d43793d80baa20c6c60e8a48e7f3a0c”,
},
‘fb1358e5bd6dec072801298238cf49ff77b79a4b’: {
name: “Dark / Background / Secondary (630)”,
mapsToName: “Light / Background / Secondary (130)”,
mapsToKey: “83704278c845a6a7ceb1f837387972ccb6d41960”,
},
“ef179b6abe6cb8779857e05a6333d33f7a2b9320”: {
name: “Dark / Background / Tertiary (700)”,
mapsToName: “Light / Background / Tertiary (200)”,
mapsToKey: “dbd02a76b7b77c1976114c04068f0fbc22015fab”,
},
“3dd0e30ce0a8287eb91ec1fbeff92031e634ed01”: {
name: “Dark / Background / Accent (500)”,
mapsToName: “Light / Interactive Text & Icons / Muted (300)”,
mapsToKey: “9328cd78a39149b070d68f98d9fe4df7a92bf67d”,
},
“11516f4b43f381afb5a6bdf2c34b9437f0eecde1”: {
name: “Dark / Background / Floating (800)”,
mapsToName: “Light / Background / Floating (White)”,
mapsToKey: “6c8b08a42f9614842e880bf7bb795014d8fbae94”,
},
// Background Modifiers
‘d6c9270834b11c99ee651f0f5072ad2c63701165’: {
name: ‘Dark / Background Mod / Hover’,
mapsToName: “Light / Background Mod / Hover”,
mapsToKey: “35307396ae29aaeb583ae65891c69ec689f0c41e”,
},
“bcf890d7a215c65deef97fb3d3f5bcebc9869bab”: {
name: “Dark / Background Mod / Active”,
mapsToName: “Light / Background Mod / Active”,
mapsToKey: “ddadf76919d9bacb925242a024dc1e2f5f517a46”,
},
“ce012db42f35fb58b4fe1d6d8b46c4905a8fad0a”: {
name: “Dark / Background Mod / Selected”,
mapsToName: “Light / Background Mod / Selected”,
mapsToKey: “5af2eaf14901472c26b641997796bdba76ee1794”,
},
“a6a3dc153f0e589408186176ebf8f20ed2f9bda3”: {
name: “Dark / Background Mod / Accent”,
mapsToName: “Light / Background Mod / Accent”,
mapsToKey: “08c7091f8d6950dc3f616afe8ed45b086f9124c7”,
},
}

Figma.ui.onmessage = msg => {

if (msg.type === ‘update-theme’) {

// If nothing is selected update the whole page
if (figma.currentPage.selection.length === 0) {
  const frameNodes = figma.currentPage.children;
  const allNodes = figma.currentPage.findAll();
  allNodes.map(selected => updateTheme(selected));
}
else if (figma.currentPage.selection.length === 1) {

  // Find all the nodes
  let node = figma.currentPage.selection[0];
  if ( isFrameOrGroup(node) ) { 
    let allNodes = node.findAll();
    // Update the nodes
    allNodes.map(selected => updateTheme(selected));
  }
  
}
else {
  let allNodes:any[] = [];
  let nodeLength = figma.currentPage.selection.length;

  // Find all the children nodes from the selected layers
  for (let i = 0; i < nodeLength; i++) {
    let node = figma.currentPage.selection[i];
    if ( isFrameOrGroup(node) ) 
    { 
      let foundChildren = node.findAll();
      allNodes.push(foundChildren);
      // Update the nodes
       
    }

   // allNodes.push(figma.currentPage.selection[i].findAll());
  }

  allNodes.forEach(function(selectedNode) {
    selectedNode.map(selected => updateTheme(selected));
  });
}

}

function isFrameOrGroup(node: SceneNode):node is FrameNode | GroupNode {
return node.type === ‘FRAME’ || node.type === ‘GROUP’
}

function updateTheme(node) {
switch (node.type) {
case ‘COMPONENT’:
case ‘INSTANCE’:
case ‘RECTANGLE’:
case ‘ELLIPSE’:
case ‘POLYGON’:
case ‘STAR’:
case ‘LINE’:
case ‘BOOLEAN_OPERATION’:
case ‘FRAME’:
case ‘VECTOR’: {
// Check to see if the node has a style
if (node.fillStyleId) {
// Fetch the style by using the ID.
let style = Figma.getStyleById(node.fillStyleId);
// Pass in the layer we want to change, the style the node has
// and the set of mappings we want to check against.
replaceStyles(node, style, themeMapping);
} else if (node.backgroundStyleId) {
// Some elements have backgrounds instead of fills.
let style = Figma.getStyleById(node.backgroundStyleId);
replaceBackground(node, style, themeMapping);
}
break
}
case ‘TEXT’: {
if (node.fillStyleId) {
let style = Figma.getStyleById(node.fillStyleId);
replaceStyles(node, style, themeMapping);
}
}
default: {
// do nothing
}
}
}

// Replaces fills with corresponding styles
function replaceStyles(node, style, mappings) {
// Find the style the ID corresponds to in the team library
let importedStyle = Figma.importStyleByKeyAsync(style.key);

// Once the promise is resolved, then see if the
// key matches anything in the mappings object.
importedStyle.then((object) => {

  // If it's null, no mapping exists yet.
  if (mappings[object.key] !== undefined) {
    let mappingStyle = mappings[object.key];

    // Use the mapping value to fetch the official style.
    let newStyle = figma.importStyleByKeyAsync(mappingStyle.mapsToKey);

    newStyle.then(function(object) {
      // Update the current style with the mapping.
      node.fillStyleId = object.id;
    });
  }
});

}

// Updates backgrounds with styles @todo combine this function with replaceStyles
function replaceBackground(node, style, mappings) {
let importedStyle = Figma.importStyleByKeyAsync(style.key);

importedStyle.then((object) => {
  if (mappings[object.key] !== undefined) {
    let mappingStyle = mappings[object.key];
  
    let newStyle = figma.importStyleByKeyAsync(mappingStyle.mapsToKey);

    newStyle.then(function(object) {
      node.backgroundStyleId = object.id;
    });
  }
});

}

Figma.closePlugin();
};