mod.ts

// Drake API.
export {
  abort,
  debug,
  DrakeError,
  env,
  glob,
  log,
  outOfDate,
  quote,
  readFile,
  sh,
  shCapture,
  ShCaptureOpts,
  ShOpts,
  ShOutput,
  touch,
  updateFile,
  writeFile
} from "./lib/utils.ts";
export { desc, execute, run, task, vers };

import { existsSync } from "https://deno.land/std@v0.38.0/fs/mod.ts";
import * as path from "https://deno.land/std@v0.38.0/path/mod.ts";
import { help } from "./lib/help.ts";
import { Action, TaskRegistry } from "./lib/tasks.ts";
import { abort, env, parseEnv } from "./lib/utils.ts";

const DRAKE_VERS = "0.15.1";

env("--abort-exits", true);

/** Global task registry. */
const taskRegistry = new TaskRegistry();

// Parse command-line options into Drake environment.
parseEnv(Deno.args.slice(), env);

if (env("--help")) {
  help();
} else if (env("--version")) {
  console.log(vers());
} else {
  // Caclulate drakefile path relative to cwd prior to processing --directory option.
  let drakefile = env("--drakefile") ?? "Drakefile.ts";
  if (!path.isAbsolute(drakefile)) {
    drakefile = path.join(Deno.cwd(), drakefile);
  }
  env("--drakefile", drakefile);

  if (env("--directory")) {
    const dir = env("--directory");
    if (!existsSync(dir) || !Deno.statSync(dir).isDirectory()) {
      abort(`--directory missing or not a directory: ${dir}`);
    }
    Deno.chdir(dir);
  }
}

/** Returns the Drake version number string. */
function vers(): string {
  return DRAKE_VERS;
}

/** Set description of next registered task. */
function desc(description: string): void {
  taskRegistry.desc(description);
}

/**
 * Create and register a task.
 * @param name - A unique task name.
 * @param prereqs - An array of prerequisite task names i.e. the names of tasks to be run prior to executing the task action function.
 * @param action - An optional function that is run if the task is selected for execution.
 */
function task(
  name: string,
  prereqs: string[] = [],
  action?: Action,
): void {
  taskRegistry.register(name, prereqs, action);
}

/**
 * Execute named tasks along with their prerequisite tasks (direct and indirect). If no `names` are
 * specified then the command-line tasks are run. If no command-line tasks were specified the
 * default task (set in `env("--default-task")`) is run.
 *
 * Task execution is ordered such that prerequisite tasks are executed prior to their parent task.
 * The same task is never run twice.
 */
async function run(...names: string[]) {
  if (env("--help") || env("--version")) {
    return;
  }
  if (env("--list-tasks") || env("--list-all")) {
    taskRegistry.list().forEach((t) => console.log(t));
  } else {
    if (names.length === 0) {
      names = env("--tasks");
      if (names.length === 0 && env("--default-task")) {
        names.push(env("--default-task"));
      }
    }
    if (names.length === 0) {
      abort("no task specified");
    }
    await taskRegistry.run(...names);
  }
}

/**
 * Unconditionally execute task action functions ignoring task prerequisites.
 *
 * - If `names` is a task name string execute the task action.
 * - If `names` is an array of task names execute their actions asynchronously.
 * - Silently skip tasks that have no action function.
 */
async function execute(names: string | string[]) {
  await taskRegistry.execute(names);
}