const fs = require('fs')
const path = require('path')
const utils = require('./utils')

const default_options = {
    '-v': 'Verbose output level=debug.',
    '-vv': 'Verbose output level=trace.'
}

function printCommandUsage(command) {
    if(command.name === '?' || command.name === 'help') {
        return
    }
    console.log(`\n[${command.name}]\n${command.description || ''}`)
    if(command.usage && command.usage.options) {
        Object.entries(command.usage.options)
            .forEach(entry => console.log(`\t ${utils.formatColumns(entry[0], entry[1], 48, '.')}`))
    }   
}


function printCompleteUsage(commands) {
    Object.values(commands).sort((a, b) => a.name.localeCompare(b.name)).forEach(printCommandUsage)
}

function load() {

    let commands = fs.readdirSync(path.join(__dirname, 'cmd'))
            .filter(file => file.startsWith("cmd"))
            .reduce((result, item) => {
                let name = item.replace(/^cmd\./, '').replace(/\.js$/, '');
                let command_path = path.join(__dirname, 'cmd', item); 
                let command = require(command_path)
                
                command.name = result.name || name
                command.usage = command.usage || {}
                command.usage.options = command.usage.options || {}
                command.usage.options = {
                    ...command.usage.options,
                    ... default_options
                }
                command.printUsage = () => printCommandUsage(command)
                let run_command = command.run
                command.run = (args) => {
                    if(args['?'] || args.help) {
                        printCommandUsage(command)
                        return
                    }
                    return run_command(args)
                }

                result[name] = command
                return result
            }, {})

    commands.help = { name: 'help', run: () => printCompleteUsage(commands) }
    commands['?'] = { name: '?', run: () => printCompleteUsage(commands) }


    return commands
}

module.exports.load = load