cli.ts

import { parse } from "https://deno.land/std@0.100.0/flags/mod.ts";
import { json2yaml } from "./mod.ts";
import { VERSION } from "./version.ts";

function printVersion(): void {
  console.log(`json2yaml ${VERSION}`);
}

function printHelp(): void {
  printVersion();
  console.log("Converts a JSON string to a (pretty) YAML string 🦕");
  console.log();
  console.log("Docs: https://deno.land/x/json2yaml");
  console.log("Bugs: https://github.com/rikilele/json2yaml/issues");
  console.log();
  console.log("USAGE:");
  console.log(
    "    deno run --allow-read https://deno.land/x/json2yaml/cli.ts [OPTIONS] -- FILE",
  );
  console.log();
  console.log("OPTIONS:");
  console.log("    -h, --help           Print help information");
  console.log("    -v, --version        Print version information");
  console.log(
    "    -s, --spaces <n>     Set number of spaces > 1 used for indents",
  );
  console.log();
  console.log("FILE:");
  console.log("    A path to a file containing a valid JSON string");
}

function executeConversion(filePath: string, numSpaces: number) {
  try {
    const decoder = new TextDecoder("utf-8");
    const fileContents = Deno.readFileSync(filePath);
    const jsonString = decoder.decode(fileContents);
    const yamlString = json2yaml(jsonString, numSpaces);
    const encoder = new TextEncoder();
    const outputContent = encoder.encode(yamlString);
    Deno.stdout.writeSync(outputContent);
    Deno.exit(0);
  } catch (e) {
    console.log(`Failed to convert file ${filePath}`);
    console.log(e);
    Deno.exit(1);
  }
}

function cli() {
  const parsedArgs = parse(Deno.args, {
    "--": true,
    alias: {
      h: ["help"],
      v: ["version"],
      s: ["spaces"],
    },
  });

  if (parsedArgs.help) {
    printHelp();
    Deno.exit(0);
  }

  if (parsedArgs.version) {
    printVersion();
    Deno.exit(0);
  }

  if (parsedArgs["--"].length === 0) {
    printHelp();
    Deno.exit(0);
  }

  const filePath = parsedArgs["--"][0];
  const numSpaces = isNaN(parsedArgs.s) || parsedArgs.s < 2 ? 2 : parsedArgs.s;
  executeConversion(filePath, numSpaces);
}

if (import.meta.main) {
  cli();
}