cliUtils service

const optionPattern = /^-([a-z]|-[a-z\-]+)$/;

export default {
    create(){
        if(this.context.cliUtils) return this.context.cliUtils;

        let args = [...this.args];
    
        const extractArg = (_default) => {
            if(args[0] && !args[0].match(optionPattern)){
                return args.shift();
            }
            return _default;
        };
    
        const extractArgs = () => {
            const out = [];
            while(args[0] && !args[0].match(optionPattern)){
                out.push(args.shift())
            }
            return out;
        };
    
        const extractFields = () => extractArgs().map(arg => {
            const matches = arg.match(/^(\^|)([^:]*)(:|)(.*)$/);
            const mandatory = matches[1] == '^';
            const name = this.inflector.camelize(matches[2]);
            const type =  matches[4] || 'string';
            return {
                mandatory,
                name,
                type
            };
        });
    
        const extractOptions = (_default = {}) => {
            const out = {};
            let currentName;
            while(args.length){
                const arg = args.shift();
                const matches = arg.match(optionPattern);
                if(matches){
                    currentName = this.inflector.camelize(matches[1]);
                    if(out[currentName] === undefined){
                        out[currentName] = [];
                    }
                } else if(currentName){
                    out[currentName].push(arg);
                }
            }
            Object.keys({ ...out, ..._default }).forEach(name => {
                const value = out[name];
                if(value === undefined){
                    out[name] = _default[name];
                } else if(!value.length){
                    out[name] = true;
                } else if(!Array.isArray(_default[name])){
                    out[name] = value.join(' ');
                }
            });
            return out;
        };
    
        const resetArgs = () => args = [..._args];
    
        this.context.cliUtils = {
            extractArg,
            extractArgs,
            extractFields,
            extractOptions,
            resetArgs
        };

        return this.context.cliUtils;
    }
};