import { color } from 'rslog';

declare global {

const RSTACK_VERSION: string;

}

export type HelpItem = readonly [label: string, description: string];

export type HelpSection =

| {

title: string;

items: readonly HelpItem[];

}

| {

content: string;

dim?: boolean;

};

export type HelpDefinition = {

usage: string;

description?: string;

sections?: readonly HelpSection[];

};

export const hasHelpFlag = (args: readonly string[]): boolean => {

const end = args.indexOf('--');

const flags = end === -1 ? args : args.slice(0, end);

return flags.some((flag) => flag === '-h' || flag === '--help');

};

const renderItems = (items: readonly HelpItem[]): string => {

const labelWidth = items.reduce((width, [label]) => Math.max(width, label.length), 0);

return items

.map(([label, description]) => ` ${label.padEnd(labelWidth)} ${description}`)

.join('\n');

};

const renderSection = (section: HelpSection): string => {

if ('items' in section) {

return `${color.cyan(section.title)}:\n${renderItems(section.items)}`;

}

return section.dim ? color.dim(section.content) : section.content;

};

export const renderHelp = ({ usage, description, sections = [] }: HelpDefinition): string => {

const blocks = [

color.bold(`Rstack v${RSTACK_VERSION}`),

`${color.cyan('Usage')}:\n${color.yellow(` $ ${usage}`)}`,

];

if (description) {

blocks.push(description);

}

blocks.push(...sections.map(renderSection));

return blocks.join('\n\n');

};