c4dslbuilder/lib/utilities/mermaid-processor.js

A CLI tool designed to compile a folder structure of markdowns and mermaid files into a site, pdf, single file markdown or a collection of markdowns with links - inspired by c4builder

import path from 'node:path';
import chalk from 'chalk';
import { promisify } from 'node:util';
import { execFile } from 'node:child_process';
import { CliLogger } from './cli-logger.js';
import { Paths } from './paths.js';
import { SafeFiles } from './safe-files.js';
export class MermaidProcessor {
    safeFiles;
    paths;
    logger;
    constructor(safeFiles = new SafeFiles(), paths = new Paths(), logger = new CliLogger(MermaidProcessor.name)) {
        this.safeFiles = safeFiles;
        this.paths = paths;
        this.logger = logger;
    }
    async generateUniqueMmdFilename(directory) {
        let index = 1;
        let name = `mmd_${index}.svg`;
        let fullPath = `${directory}/${name}`;
        while (await this.safeFiles.pathExists(fullPath)) {
            index++;
            name = `mmd_${index}.svg`;
            fullPath = `${directory}/${name}`;
        }
        return name;
    }
    async diagramFromMermaidString(content, outputPath) {
        const packageRoot = path.resolve(this.paths.getPathFromMeta(import.meta.url), '../..');
        const mmdcPath = path.join(packageRoot, 'node_modules/.bin/mmdc');
        const execFileAsync = promisify(execFile);
        let tempFile;
        try {
            const outputDir = path.dirname(outputPath);
            await this.safeFiles.ensureDir(outputDir);
            tempFile = path.join(outputDir, `temp_${Date.now()}.mmd`);
            await this.safeFiles.writeFile(tempFile, content);
            this.logger.log(chalk.blue(`Generating Mermaid diagram: ${outputPath}`));
            await execFileAsync('node', [mmdcPath, '-i', tempFile, '-o', outputPath]);
        }
        catch (error) {
            this.logger.error(chalk.red('Error generating Mermaid diagram:'), error);
            return false;
        }
        // cleanup
        try {
            await this.safeFiles.removeFile(tempFile);
        }
        catch (error) {
            this.logger.error(`Failed to delete temporary file ${tempFile}`, error);
        }
        // validate
        try {
            await this.safeFiles.accessFile(outputPath);
            this.logger.log(chalk.green(`Successfully generated diagram: ${outputPath}`));
            return true;
        }
        catch (error) {
            this.logger.error(`Failed to generate diagram: ${outputPath}`, error);
            return false;
        }
    }
}