thi-ng/umbrella

import type { IObjectOf, Maybe } from "@thi.ng/api";
import { illegalArgs } from "@thi.ng/errors/illegal-arguments";
import { StreamLogger } from "@thi.ng/logger/stream";
import { padRight } from "@thi.ng/strings/pad-right";
import { PRESET_ANSI16, PRESET_NONE } from "@thi.ng/text-format/presets";
import type {
    CLIAppConfig,
    Command,
    CommandCtx,
    ParseResult,
    UsageOpts,
} from "./api.js";
import { parse } from "./parse.js";
import { usage } from "./usage.js";

export const cliApp = async <
    OPTS extends object,
    CTX extends CommandCtx<OPTS, OPTS>
>(
    config: CLIAppConfig<OPTS, CTX>
) => {
    const argv = config.argv || process.argv;
    const isColor = !process.env.NO_COLOR;
    const usageOpts = {
        prefix: "",
        color: isColor,
        ...config.usage,
    };
    try {
        let cmdID: string;
        let cmd: Command<any, OPTS, CTX>;
        let start = config.start ?? 2;
        if (config.single) {
            // single command mode, use 1st available name
            cmdID = Object.keys(config.commands)[0];
            if (!cmdID) illegalArgs("no command provided");
            cmd = config.commands[cmdID];
        } else {
            cmdID = argv[start];
            cmd = config.commands[cmdID];
            usageOpts.prefix += __descriptions(config.commands);
            if (!cmd) __usageAndExit(config, usageOpts);
            start++;
        }
        let parsed: Maybe<ParseResult<OPTS>>;
        try {
            parsed = parse<OPTS>({ ...config.opts, ...cmd.opts }, argv, {
                showUsage: true,
                usageOpts,
                start,
            });
        } catch (_) {}
        if (!parsed) process.exit(1);
        if (cmd.inputs !== undefined && cmd.inputs !== parsed.rest.length) {
            process.stderr.write(`expected ${cmd.inputs || 0} input(s)\n`);
            __usageAndExit(config, usageOpts);
        }
        const ctx: CTX = await config.ctx(
            {
                logger: new StreamLogger(process.stderr, config.name, "INFO"),
                format: isColor ? PRESET_ANSI16 : PRESET_NONE,
                opts: parsed.result,
                inputs: parsed.rest,
            },
            cmd
        );
        await cmd.fn(ctx);
        if (config.post) await config.post(ctx, cmd);
    } catch (e) {
        process.stderr.write((<Error>e).message + "\n\n");
        process.exit(1);
    }
};

const __usageAndExit = (
    config: CLIAppConfig<any, any>,
    usageOpts: Partial<UsageOpts>
) => {
    process.stderr.write(usage(config.opts, usageOpts));
    process.exit(1);
};

const __descriptions = (commands: IObjectOf<Command<any, any, any>>) =>
    [
        "\nAvailable commands:\n",
        ...Object.keys(commands).map(
            (x) => `${padRight(16)(x)}: ${commands[x].desc}`
        ),
        "\n",
    ].join("\n");