package org.ossnipes.snipes.bot;

public class ArgumentParser
{
    private static final ArgumentParser inst = new ArgumentParser();

    public static ArgumentParser getParser()
    {
        return inst;
    }

    public static ArgumentParser getParser(boolean debugCreateNew)
    {
        return debugCreateNew ? new ArgumentParser() : inst;
    }

    public void parseArgs(Configuration c, String[] args)
    {
        int i = 0, j;
        String arg;

        while (i < args.length && args[i].startsWith("-"))
        {
            arg = args[i++];

            if (arg.equals("--verbose"))
            {
                this.onVerbose(c);
            }

            else if (arg.equals("--define"))
            {
                if (i < args.length)
                {
                    this.onDefine(c, arg, args[i++]);
                }
                else
                {
                    System.err
                            .println("--define requires a property=value argument.");
                    break;
                }

            }

            // Check for small flag args.
            else
            {
                for (j = 0; j < arg.length(); j++)
                {
                    char flag = arg.charAt(j);
                    switch (flag)
                    {
                        case '-':
                        {
                            // The initial -
                            break;
                        }
                        case 'v':
                        {
                            // Verbose on
                            this.onVerbose(c);
                            break;
                        }
                        case 'D':
                        {
                            if (i < args.length)
                            {
                                this.onDefine(c, arg, args[i++]);
                            }
                            else
                            {
                                System.err
                                        .println("-D requires a property=value argument.");
                                break;
                            }
                            break;
                        }
                        default:
                            System.err.println("Illegal option " + flag);
                        break;
                    }
                }
            }
        }
        if (i != args.length)
        {
            System.exit(Exit.EXIT_INCORRECTARGSSYN.ordinal());
        }
    }

    private void define(Configuration c, String key, String value)
    {
        c.setTempProperty(key, value);
    }

    private void onVerbose(Configuration c)
    {
        this.define(c, "verbose", "TRUE");
    }

    private boolean onDefine(Configuration c, String arg, String arg2)
    {
        String[] eqSplit = arg2.split("=");
        if (eqSplit.length != 2)
        {
            System.err
                    .println("Define directive: Argument invalid. Argument should look like: \""
                            + arg + " myproperty=myvalue\"");
            return false;
        }
        else
        {
            this.define(c, eqSplit[0], eqSplit[1]);
            return true;
        }
    }
}