const { packageExists } = require('../utils/package-exists');
const webpack = packageExists('webpack') ? require('webpack') : undefined;
const logger = require('../utils/logger');

const PluginName = 'webpack-cli';

class WebpackCLIPlugin {
    constructor(options) {
        this.options = options;
    }

    async apply(compiler) {
        const compilers = compiler.compilers || [compiler];

        for (const compiler of compilers) {
            if (this.options.progress) {
                const { ProgressPlugin } = compiler.webpack || webpack;

                let progressPluginExists;

                if (compiler.options.plugins) {
                    progressPluginExists = Boolean(compiler.options.plugins.find((plugin) => plugin instanceof ProgressPlugin));
                }

                if (!progressPluginExists) {
                    if (typeof this.options.progress === 'string' && this.options.progress !== 'profile') {
                        logger.error(
                            `'${this.options.progress}' is an invalid value for the --progress option. Only 'profile' is allowed.`,
                        );
                        process.exit(2);
                    }

                    const isProfile = this.options.progress === 'profile';

                    new ProgressPlugin({ profile: isProfile }).apply(compiler);
                }
            }
        }

        const compilationName = (compilation) => (compilation.name ? ` ${compilation.name}` : '');

        compiler.hooks.watchRun.tap(PluginName, (compilation) => {
            const { bail, watch } = compilation.options;
            if (bail && watch) {
                logger.warn('You are using "bail" with "watch". "bail" will still exit webpack when the first error is found.');
            }

            logger.success(`Compilation${compilationName(compilation)} starting...`);
        });

        compiler.hooks.done.tap(PluginName, (compilation) => {
            logger.success(`Compilation${compilationName(compilation)} finished`);

            process.nextTick(() => {
                if (compiler.watchMode) {
                    logger.success('watching files for updates...');
                }
            });
        });
    }
}

module.exports = WebpackCLIPlugin;