tom-weatherhead/thaw-interpreter

// tom-weatherhead/thaw-interpreter/src/cli.ts

import { LanguageSelector } from 'thaw-interpreter-types';

import { readEvaluatePrintLoop } from 'thaw-repl';

import { createInterpreter } from './common/interpreter-factory';

import { executeScript } from './common/script-executor';

import { scriptExecutorLCAug } from './languages/lambda-calculus-augmented-syntax/script-executor';

function printUsageMessage() {
    process.stdout.write('\n');
    process.stdout.write('Usage: $ intrprtr [language name]\n');
    process.stdout.write('\n');
    process.stdout.write('E.g.: $ intrprtr lisp\n');
    process.stdout.write('\n');
    process.stdout.write('Available languages: minimal, chapter1, lisp, scheme, sasl, prolog');
    process.stdout.write('\n');
}

function languageNameStringToLanguageSelector(languageName: string): LanguageSelector {
    switch (languageName) {
        case 'minimal':
            return LanguageSelector.MinimalLanguage;

        case 'chapter1':
            return LanguageSelector.Chapter1;

        case 'lisp':
            return LanguageSelector.LISP;

        case 'apl':
            return LanguageSelector.APL;

        case 'scheme':
            return LanguageSelector.Scheme;

        case 'sasl':
            return LanguageSelector.SASL;

        case 'clu':
            return LanguageSelector.CLU;

        case 'smalltalk':
            return LanguageSelector.Smalltalk;

        case 'prolog':
            // return LanguageSelector.Prolog; // Kamin's notation
            return LanguageSelector.Prolog2; // Standard

        default:
            throw new Error('languageNameStringToLanguageSelector()');
    }
}

function doInteractiveMode(languageName: string): void {
    process.stdout.write('\nThis is the command line interface for thaw-interpreter\n\n');

    if (process.argv.length < 3) {
        process.stdout.write('Error: No language specified.\n');
        printUsageMessage();
        return;
    }

    const languageSelector = languageNameStringToLanguageSelector(languageName);

    // if (languageSelector === undefined) {
    //     process.stdout.write(`Error: No interpreter available for language '${languageName}'.\n`);
    //     printUsageMessage();
    //     return;
    // }

    const interpreter = createInterpreter(languageSelector);

    const isExitCommand = (command: string) => command === 'exit';
    const evaluate = (command: string) => interpreter.evaluateFromString(command);

    readEvaluatePrintLoop(isExitCommand, evaluate)
        .then(() => {
            // process.stdout.write('readEvaluatePrintLoop() resolved successfully.\n\n');
        })
        .catch((error: unknown) => {
            process.stderr.write(`Error in readEvaluatePrintLoop(): ${typeof error} ${error}\n`);
        });
}

function runScript(languageName: string, scriptFilenames: string[]): void {
    // let fnScriptExecutor: () => Promise<void>;
    let scriptExecutionPromise: Promise<void>;

    if (languageName === 'lcaug') {
        scriptExecutionPromise = scriptExecutorLCAug(scriptFilenames[0]);
    } else {
        scriptExecutionPromise = executeScript(
            languageNameStringToLanguageSelector(languageName),
            scriptFilenames
        );
    }

    scriptExecutionPromise.then().catch((error: unknown) => {
        console.error('Script execution error:', typeof error, error);
    });
}

export function driver(argv: string[]): void {
    if (argv.length <= 2) {
        // TODO: Use process.stderr.write() ?
        console.error('Usage: intrprtr language-name [script-path-list]');
        process.exit(1);
    }

    const languageName = argv[2];
    const supportedLanguages = [
        'apl',
        'chapter1',
        'clu',
        'lcaug',
        'lisp',
        'minimal',
        'prolog',
        'scheme',
        'smalltalk'
    ];

    if (supportedLanguages.indexOf(languageName) < 0) {
        console.error(`Error: Unknown language name '${languageName}'.`);
        console.error('The language name must be one of:', supportedLanguages.join(', '));
        process.exit(1);
    }

    if (argv.length === 3) {
        // Interactive mode
        doInteractiveMode(languageName);
    } else {
        // Script mode
        runScript(languageName, argv.slice(3));
    }
}