import toml;

public{
  import std.stdio : writeln;
  import std.file : read;
  import std.array;
  import std.string;
  import std.uni : isWhite, isAlpha, isAlphaNum;
  import std.ascii : isDigit;
  import std.conv : to;
  import std.algorithm;
}

//import dopp_lexer : tokenize, isKeyword;
//import dopp_parser : parse;


TOMLDocument toml_s;


export enum TokenType{
  Identifier,
  Keyword,
  Integer,
  Float,
  String,
  Symbol,
  Whitespace
}


export struct Token{
  TokenType type;
  string lexeme;
  
  // for debug
  string toString(){
    import std.format : format;
    //return "Token(type: %d, lexeme: %s)".format(type, lexeme);
    return "Token = type: %d, lexeme: %s\n".format(type, lexeme);
  }
}



// ./dopp -t == shortened for test (onto single .de -> .d module)
// ./dopp -d "/test" -o "/test2" == input dir path + output dir path (default output dir = input dir)
// ./dopp -f test.de -o test.d == input file name + output file name (default output file name = input file name [but .d instead .de] )
// ./dopp -f "/test/test.de" -o "/result/test.d" == input file path + output file path (default output file name and path = input file name and path [but .d instead .de] )
bool is_valid_argv(ref string[] argv){
  //ulong num = argv[1 .. $].length; // uint64
  ulong num = argv.length; // uint64
  if(num != 1 && num != 2 && num != 4){
    return false;
  
  }else if(num == 1){ // one argument only (just filename or /path/filename) == shortened ./dopp -f test.de = ./dopp test.de; or -t == shortened for test (onto single .de -> .d module)
    if( (argv[0] == "-t") || (argv[0].length >= 4 && argv[0][$-3 .. $] == ".de") ){
      return true;
    }else{
      return false;
    }
  
  }else if(num == 2){ // two arguments = input file name/path or input dir path
    if(argv[0] != "-d" && argv[0] != "-f"){
      return false;
    
    }else if(argv[0] == "-f"){ // must be file
       if(argv[1].length >= 4 && argv[1][$-3 .. $] == ".de"){
         return true;
       }else{
         return false;
       }
    
    }else{ // dir
      if(argv[1].length > 0){
        return true;
      }else{
        return false;
      }
    }
  
  }else{ // num == 4
    string[] argv2 = argv[0 .. 2];
    if( is_valid_argv(argv2) ){ // valid first 2
      string[] argv4 = argv[2 .. $];
      if( argv[2] != "-o" ){ // valid next - last 2
        return false;
      }else if(argv[0] == "-f"){ // must be file
        if(argv[3].length >= 3 && argv[3][$-2 .. $] == ".d"){
          return true;
        }else{
          return false;
        }
      
      }else{ // dir
        if(argv[3].length > 0){
          return true;
        }else{
          return false;
        }
      }
      
    }else{
      return false;
    }
  }
}



//void main(string[] argv){
int main(string[] argv){
  
  toml_s = parseTOML(cast(string)read("dopp.toml"));
  writeln("indent_matter: ", toml_s["indent_matter"]); // 4
  //writeln("xyz: ", toml_s["xyz"]); // Address boundary error || Segmentation fault (core dumped)
  writeln("indent_matter in: ", "indent_matter" in toml_s);
  writeln("xyz in: ", "xyz" in toml_s);
  // todo function - config and default values
  
  /*
  int i = 0;
  foreach(string s; argv[1 .. $]){
    writeln(s);
    i++;
  }
  writeln("i = ", i);
  */
  
  string[] argv1 = argv[1 .. $]; // argv[0] always = program name ( ./dopp in my case in linux )
  bool valid1 = is_valid_argv(argv1);
  writeln("valid1 = ", valid1);
  
  if(!valid1){
    return 0;
  }
  
  
  
  //string source = `if (x > 0) { writeln("Positive"); }`;
  //auto tokens = tokenize(source);
  //writeln(tokens);
  //parse(tokens);
  
  return 1;
}


unittest{
  assert( is_valid_argv([]) == false );
  assert( is_valid_argv([""]) == false );
  assert( is_valid_argv(["-t"]) == true );
  assert( is_valid_argv(["-d"]) == false );
  assert( is_valid_argv(["-d", ""]) == false );
  assert( is_valid_argv(["-d", "/test"]) == true );
  assert( is_valid_argv(["-d", "/test", "-o", "/test2"]) == true );
  assert( is_valid_argv(["test.de"]) == true );
  assert( is_valid_argv(["-f", "test.de"]) == true );
  assert( is_valid_argv(["-f", "test.de", "-o", "test.d"]) == true );
  assert( is_valid_argv(["test.txt"]) == false );
  assert( is_valid_argv(["-f", "test.txt"]) == false );
  assert( is_valid_argv(["-f", "test.txt", "-o", "test.d"]) == false );
  assert( is_valid_argv(["-f", "test.de", "-o", "test.txt"]) == false );
}

// ./dopp -t == shortened for test (onto single .de -> .d module)
// ./dopp -d "/test" -o "/test2" == input dir path + output dir path (default output dir = input dir)
// ./dopp -f test.de -o test.d == input file name + output file name (default output file name = input file name [but .d instead .de] )
// ./dopp -f "/test/test.de" -o "/result/test.d" == input file path + output file path (default output file name and path = input file name and path [but .d instead .de] )