name | Text2Dia |
description | Convert text / code to diagrams and diagrams back to text. Supports Math (tex), Mermaid, PlantUML etc. |
icon | sync_alt |
instructions | This plugin allows users to easily convert text to diagrams and diagrams back to text. It supports various diagram types including Math (tex), Mermaid, PlantUML, Graphviz, etc.  To convert diagram back to text, use the "Convert to Text" menu:  The plugin also has tight integration for math. You can also create diagram using an {expression}. |
The images are generated by the free and open source service kroki.io.
Code:
{
replaceText: {
"Convert to Dia": async function (app, text) {
text = text.trim();
let {type, text: parsedText} = await this._parseUserIntentFromText(app, text);
if(type == 'cancel') return;
await this._toDiagram(app, type, text, parsedText)
return null;
}
},
insertText: {
"Create Diagram": async function (app) {
let {type, text} = await this._parseUserIntentFromText(app, null);
if(type == 'cancel') return;
text = text.trim();
await this._toDiagram(app, type, text, text)
return null;
}
},
imageOption: {
"Convert to Text": async function (app, image) {
await this._toText(app, image);
return null;
}
},
async _parseUserIntentFromText(app, text) {
if (typeof text == "string" && text.match(/^\$\$(.*?)\$\$$/s)) {
return {type: 'tex-display', text: text.replace(/^\$\$(.*?)\$\$$/s, '$1')};
}
else if (typeof text == "string" && text.match(/^\$(.*?)\$$/s)) {
return {type: 'tex', text: text.replace(/^\$(.*?)\$$/s, '$1')};
}
const promptInputs = [
{
label: "Diagram Type", type: "select", options: [
{label: "Tex (Inline)", value: 'tex'},
{label: "Tex (Display)", value: 'tex-display'},
{label: "Mermaid", value: 'mermaid'},
{label: "PlantUML", value: 'plantuml'},
{label: "Graphviz", value: 'graphviz'},
{label: "Ditaa", value: 'ditaa'},
{label: "DBML", value: 'dbml'},
]
, value: 'ditaa'
},
];
let type;
if (text == null) {
const arr = await app.prompt("Options for creating image:", {
inputs: [{ label: "Text / Code", placeholder: "+--+\n|A |\n+--+", type: "text" }, ...promptInputs]
});
if(!arr) return {type: 'cancel'};
text = arr[0];
if(!text || text == '') return {type: 'cancel'};
type = arr[1];
}
else {
type = await app.prompt("Options for creating image:", {
inputs: promptInputs
});
if(!type) return {type: 'cancel'};
}
return {type, text};
},
async _toDiagram(app, type, text, parsedText) {
try {
console.log(text);
let response;
if (type == null) return;
else if (type === 'tex' || type === 'tex-display') {
// https://www.overleaf.com/learn/latex/Font_sizes%2C_families%2C_and_styles
// https://www.overleaf.com/learn/latex/Using_colours_in_LaTeX
response = await fetch(`https://kroki.io/tikz/svg`, {
method: 'POST',
headers: {
'Content-Type': 'application/x-www-form-urlencoded'
},
body: `\\documentclass{article}
\\usepackage{amsmath}
\\usepackage[dvipsnames]{xcolor}
\\usepackage[active,tightpage]{preview}
\\PreviewEnvironment{equation*}
\\setlength\\PreviewBorder{0.125pt}
\\begin{document}
\\${type === 'tex-display' ? 'huge' : 'large'}
\\begin{equation*}
{${type === 'tex-display' ? '\\displaystyle' : ''} \\color{Emerald} ${parsedText}}
\\end{equation*}
\\end{document}`
});
} else if (type === 'mermaid' || type === 'plantuml' || type === 'graphviz' || type === 'ditaa' || type === 'dbml') {
response = await fetch(`https://kroki.io/${type}/svg`, {
method: 'POST',
headers: {
'Content-Type': 'application/x-www-form-urlencoded'
},
body: parsedText
});
}
if (!response)
throw new Error('No response from kroki.io');
if (!response.ok) {
let error = await response.text();
throw new Error(error);
}
const blob = await response.blob();
const svgDataURL = await this._dataURLFromBlob(blob);
const pngDataURL = await this._svgToPng(svgDataURL);
const noteHandle = {uuid: app.context.noteUUID};
const fileURL = await app.attachNoteMedia(noteHandle, pngDataURL);
const appendedFileURL = fileURL + '?text=' + window.encodeURIComponent(window.btoa(text));
app.context.replaceSelection(``)
return null;
} catch (e) {
app.alert('Failed _toDiagram - ' + e);
}
},
async _toText(app, image) {
try {
const url = new URL(image.src);
if (url.searchParams.get("text") == null) throw new Error("No text information found in image. It is possible that the image was not created by this plugin.");
let text = window.atob(window.decodeURIComponent(url.searchParams.get("text")));
console.log(text);
app.context.replaceSelection(text);
} catch (e) {
app.alert('Failed _toText - ' + e);
}
},
async _svgToPng(svgBase64) {
return new Promise(async function (resolve, reject) {
let image = new Image();
image.src = svgBase64;
image.onload = function () {
let canvas = document.createElement('canvas');
canvas.width = image.width;
canvas.height = image.height;
let context = canvas.getContext('2d');
context.drawImage(image, 0, 0);
let output = canvas.toDataURL('image/png');
resolve(output);
};
});
},
async _dataURLFromBlob(blob) {
return new Promise((resolve, reject) => {
const reader = new FileReader();
reader.onload = event => {
resolve(event.target.result);
};
reader.onerror = function (event) {
reader.abort();
reject(event.target.error);
};
reader.readAsDataURL(blob);
});
}
}