import inquirer from 'inquirer';
import inquirerFileTreeSelection from 'inquirer-file-tree-selection-prompt';
import colors from 'colors';
import path from 'path';
import fs from 'fs';
import Handlebars from 'handlebars';

inquirer.registerPrompt('file-tree-selection', inquirerFileTreeSelection);

const STORY_TEMPLATE_PATH = path.resolve(__dirname, '../../templates/story-template.js');

const storyTemplate = Handlebars.compile(fs.readFileSync(STORY_TEMPLATE_PATH, 'utf-8'));

export async function runStory(options: any) {
    const answers = await inquirer
        .prompt([
            {
                type: 'input',
                name: 'title',
                message: "What's the title of this story (the name that shows up in storybook)?",
                validate: input => {
                    if (!input) return 'A title is required';

                    return true;
                }
            },
            {
                type: 'file-tree-selection',
                name: 'storyDir',
                message: 'Where should this story be generated?',
                onlyShowDir: true,
                onlyShowValid: true,
                validate: storyDir => {
                    return !storyDir.endsWith('node_modules') && !storyDir.endsWith('.storybook');
                }
            }
        ]);

    const { storyDir, title } = answers;
    const storyName = getStoryName(storyDir);
    const lwcClassName = storyName.substring(0,1).toUpperCase() + storyName.substring(1);
    const lwcFileName = storyName + '.js';
    const lwcMetaFileName = storyName + '.js-meta.xml';
    const storyFileName = storyName + '.stories.js';
    const storyPath = path.resolve(storyDir, storyFileName);
    const lwcCustomElement = `${getStoryDirectoryName(storyDir)}-${toKebabCase(lwcClassName)}`;

    if (fs.existsSync(storyPath)) {
        console.error(colors.red(`A story already exists at: ${storyPath}`));
        runStory(options);
        return;
    }

    const story = storyTemplate({
        lwcClassName,
        lwcFileName,
        lwcCustomElement,
        lwcMetaFileName,
        title
    });

    fs.writeFileSync(storyPath, story);

    console.log(colors.green(`Successfully generated story: `) + storyPath);
}

function getStoryName(storyDir: string): string {
    return storyDir.substring(storyDir.lastIndexOf('/') + 1);
}

function toKebabCase(str: string) {
    const match = str
        .match(/[A-Z]{2,}(?=[A-Z][a-z]+[0-9]*|\b)|[A-Z]?[a-z]+[0-9]*|[A-Z]|[0-9]+/g)

    if (!match) throw new Error('Invalid file name: ' + str);

    return match.map((x: string) => x.toLowerCase())
        .join('-');
}

function  getStoryDirectoryName(storyDir: string): string {
    const storyFolderPath = storyDir.substring(0, storyDir.lastIndexOf('/'));
    return storyFolderPath.substring(storyFolderPath.lastIndexOf('/') + 1);
}