using System;
using System.Linq;
using System.IO;
using System.Text;
using System.Collections.Generic;

namespace AniNIX.Crypto {
    public  class Simple : Cipher {
        //Cipher description to be set by each cipher.
        public override String Description() { return "This is a suite of simple text ops."; }
        public override String Command() { return "simple"; }

        public Simple(Workbench w) : base (w) {}

        /// <summary> 
        /// We should be able to act on a workspace and command line. Most ciphers will sue the same syntax. Those that don't can override.
        /// </summary>
        /// <param name=workSpace>The current version of the text being worked on.</param>
        /// <param name=line>The command sequence.</param>
        /// <returns>The updated version of the workSpace</returns> 
        public override String RunCommand(String workSpace,String inputText,String[] line) {
            if (workSpace == null || line == null || line.Length < 2) {
                Console.Error.WriteLine("Malformed request.");
                return workSpace;
            }
            switch (line[1]) {
                case "shiftup": 
                    return ShiftUpper(workSpace);
                case "shiftdown":
                    return ShiftLower(workSpace);
                case "stripspace":
                    return StripSpaces(workSpace);
                case "reverse":
                    return ReverseString(workSpace);
                case "help": 
                    GetHelp();
                    return workSpace;
                default:
                    Console.Error.WriteLine("Invalid command. Type help for more.");
                    return workSpace;
            } 
        }

        /// <summary>
        /// Show the helptext for this cipher. By default, most ciphers will only have encrypt, decrypt, and help functions.
        /// </summary>
        /// <param name=line>This is the incoming line and we use it to get the cipher name</param>
        public override void GetHelp() {
            Console.WriteLine(String.Format("Help for the {0} cipher suite.\n{1}\n",Command(),Description()));
            Console.WriteLine("shiftup             -- Make all uppercase\nshiftdown           -- make all lowercase\nstripspace          -- strip spaces from String\nreverse           -- reverse the string\nhelp                -- show this helptext.");
        }


        public String ShiftUpper(String workSpace) {
            char[] changed = workSpace.ToCharArray();
            for (int i = 0; i <  changed.Length; i++) {
                if (Char.IsLower(changed[i])) {
                    changed[i] = Char.ToUpper(changed[i]);
                }
            }
            return new String(changed);
        }

        public String ShiftLower(String workSpace) {
            char[] changed = workSpace.ToCharArray();
            for (int i = 0; i <  changed.Length; i++) {
                if (Char.IsUpper(changed[i])) {
                    changed[i] = Char.ToLower(changed[i]);
                }
            }
            return new String(changed);
        }

        public String StripSpaces(String workSpace) {
            String changed = workSpace.Replace(" ","");
            return changed;
        }

        public String ReverseString(String workSpace) {
            char[] charArray = workSpace.ToCharArray();
            Array.Reverse(charArray);
            return new String(charArray);
        }


        //Simple doesn't handle encryption or decryption, but we want to use the same code for subscribing.
        public override String Encrypt(string workSpace,String ciphetText,String[] line) { return workSpace; }
        public override String Decrypt(string workSpace,String ciphetText,String[] line) { return workSpace; }
    }
}