import colors from 'colors';
import path from 'path';
import fs from 'fs';
import resolve from 'resolve';

const REGEXP_DEFAULT_PICKLIST_VALUE = /:default$/;

function obtainCustomCssProperties(brandingJsonPath: string): any {
    if (fs.existsSync(brandingJsonPath) && fs.statSync(brandingJsonPath).isFile()) {
        const brandingJson = JSON.parse(fs.readFileSync(brandingJsonPath, 'utf-8'));
        return brandingJson.reduce((acc: any, entry: any) => {
            const { type, tokens, value, id, label } = entry;
            if (['Color', 'Font', 'Image', 'Picklist', 'Slider'].includes(type.name)) {
                let effectiveValue: string;
                if (type.name === 'Picklist') {
                    const picklistValues = value.split(',');
                    const defaultPicklistValue = picklistValues.find((v: string) => REGEXP_DEFAULT_PICKLIST_VALUE.test(v));
                    const defaultPicklistVal = defaultPicklistValue ? defaultPicklistValue.split(':') : [];

                    if (defaultPicklistVal.length === 3 && defaultPicklistVal[2] === 'default') {
                        effectiveValue = defaultPicklistVal[1];
                    } else {
                        console.warn(
                            `Skipped processing entry "${id}" of type "${type.name}": No default value defined in "${value}".`
                                .yellow
                        );
                    }
                } else {
                    effectiveValue = value;
                }

                tokens.forEach((token: any) => {
                    acc.push({ type, token, value: effectiveValue, id, label });
                });
            } else {
                console.warn(`Skipped processing entry "${id}": Unknown type "${type.name}".`.yellow);
            }
            return acc;
        }, []);
    } else {
        console.warn(colors.red(`Unable to process branding JSON: The file "${brandingJsonPath}" does not exist.`));
        return [];
    }
}

function obtainCustomCssPropertiesString(brandingJsonPath: string): string {
    const cssProperties = obtainCustomCssProperties(brandingJsonPath).reduce((acc: string[], entry: any) => {
        const { type, token, value, id, label } = entry;
        let effectiveValue;
        if (type.name === 'Font') {
            effectiveValue = value ? `'${value}'` : null;
        } else {
            effectiveValue = value;
        }
        acc.push(`${token}: ${effectiveValue || "''"}; /* ID = ${id}, Type = ${type.name}, Label = ${label} */`);
        return acc;
    }, []);
    return `:root {
    ${cssProperties.join('\n    ')}
}\n`;
}

export async function buildBaseBranding(destination: string = '.storybook/assets/styles') {
    process.stdout.write(colors.blue('\tbuild base branding...'));
    const packageRootDir = process.cwd();
    const storybookStylesDir = path.resolve(packageRootDir, destination);
    if (fs.existsSync(storybookStylesDir) && fs.statSync(storybookStylesDir).isDirectory()) {
        const baseBrandingJsonPath = resolve.sync('webruntime-branding-shared/templates/base-branding.json');
        const webruntimeCssPath = path.resolve(storybookStylesDir, 'webruntime.css');
        fs.writeFileSync(webruntimeCssPath, obtainCustomCssPropertiesString(baseBrandingJsonPath), 'utf-8');
        console.log(`${webruntimeCssPath}`);
    } else {
        console.warn(colors.red(`Unable to apply branding JSON properties: The directory "${storybookStylesDir}" does not exist.`));
    }
}