/*
Rating system designed to be used in VoIP Carriers World
Copyright (C) 2013 ITsysCOM

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>
*/

package console

import (
	"bytes"
	"fmt"
	"regexp"
	"strings"

	"github.com/cgrates/cgrates/utils"
)

var (
	commands = make(map[string]Commander)
	lineR    = regexp.MustCompile(`(\w+)\s*=\s*(.+?)(?:\s+|$)`)
	jsonR    = regexp.MustCompile(`"(\w+)":(.+?)[,|}]`)
)

// Console Command interface
type Commander interface {
	FromArgs(args string, verbose bool) error // Load data from os arguments or flag.Args()
	Usage() string                            // usage message
	RpcMethod() string                        // Method which should be called remotely
	RpcParams() interface{}                   // Parameters to send out on rpc
	RpcResult() interface{}                   // Only requirement is to have a String method to print on console
	ClientArgs() []string                     // for autocompletion
}

func GetCommands() map[string]Commander {
	return commands
}

func getAvailabelCommandsErr() error {
	var keys []string
	for key, _ := range commands {
		keys = append(keys, key)
	}
	return fmt.Errorf("\n\tAvailable commands <%s>\n", strings.Join(keys, "|"))
}

// Process args and return right command Value or error
func GetCommandValue(command string, verbose bool) (Commander, error) {

	firstSpace := strings.Index(command, " ")
	if firstSpace < 0 {
		return nil, getAvailabelCommandsErr()
	}
	cmdVal, exists := commands[command[:firstSpace]]
	if !exists {
		return nil, getAvailabelCommandsErr()
	}
	if err := cmdVal.FromArgs(command[firstSpace+1:], verbose); err != nil {
		return nil, err
	}
	return cmdVal, nil
}

func ToJSON(line string) (jsn []byte) {
	jsn = append(jsn, '{')
	for _, group := range lineR.FindAllStringSubmatch(line, -1) {
		if len(group) == 3 {
			jsn = append(jsn, []byte(fmt.Sprintf("\"%s\":%s,", group[1], group[2]))...)
		}
	}
	jsn = bytes.TrimRight(jsn, ",")
	jsn = append(jsn, '}')
	return
}

func FromJSON(jsn []byte, interestingFields []string) (line string) {
	for _, group := range jsonR.FindAllSubmatch(jsn, -1) {
		if len(group) == 3 {
			if utils.IsSliceMember(interestingFields, string(group[1])) {
				line += fmt.Sprintf("%s=%s ", group[1], group[2])
			}
		}
	}
	return strings.TrimSpace(line)
}