package Tokens;

/**

* Base token handles the tokenization of simple and complex tokens, and nests itself

* to tokenize the rest of the input string.

*

* @author Keenan Leverty

* @author Peter Matern

* @author Chris Allender

*/

class BaseToken extends Token {

Token simpOrComp;

BaseToken nextBase;

boolean isComplex;

boolean isEmpty;

/**

* The constructor for the base token determines if the token starts with a complex or simple token

* then creates the corresponding token. Finally it makes a new base token with the remaining characters.

* If the input is empty, no tokens are created, and the base token is considered empty, or epsilon.

*

* @param input String containing the input passed to the base token to be tokenized.

* @param scope The current scope of the base token, used for python formatting.

*/

BaseToken(String input, int scope) {

super(input, scope);

// Checks if the input is a complex token

isComplex = input.startsWith("while") || input.startsWith("if") || input.startsWith("for") || input.startsWith("voidmain");

//Checks if the base token is epsilon

isEmpty = input == null || input == "";

// If the input is not nothing

if(!isEmpty) {

if (isComplex) { // if the input is complex

addComplexToken(); // add a complex token

} else if (input.indexOf(';') > 0) { // else the input starts with a simple token

simpOrComp= new SimpleToken(input.substring(0,input.indexOf(';') + 1), scope); // add a new simple token, ending on the first ';'

nextBase= new BaseToken(input.substring(input.indexOf(';') + 1), scope); // add a new base token with the rest of the input

}

}

}

/**

* Private function finds the end of the complex token, based on where the last '}'

* is, and the sub-scope of the token is the same.

*

* @return int the end index of the complex token in the input string

*/

private int findEndOfComplex() {

int tempScope = 0;

int endOfComplex = 0;

for (int i = input.indexOf("{"); i < input.length(); i++) {

if (input.charAt(i) == '{') {

tempScope++;

} else if (input.charAt(i) == '}') {

tempScope--;

}

if (tempScope == 0) {

endOfComplex = i;

break;

}

}

return endOfComplex;

}

/**

* Adds a new complex token to the parse tree based on where the last '}' was found to be.

* The entire token is included in the new complex token, meaning it is given the determining

* keywords of "if" "while"... The complex token will handle the formatting and nested tokens.

*/

private void addComplexToken(){

// get the end of the token

int endOfComplex = findEndOfComplex();

simpOrComp = new ComplexToken(input.substring(0, endOfComplex + 1), scope); // add a new complex token, starting at the beginning, to the '}'

nextBase= new BaseToken(input.substring(endOfComplex + 1), scope); // add a new base token, starting after the '}', to the end

}

/**

* Simple toString() returns the toString() of the token created, and the base token under it.

* If the tokens were not created, it is assumed this token is at the end of the file, or

* parent token, and the output should just be the empty string; ie: the base case.

*/

@Override

public String toString() {

String output = "";

if(simpOrComp != null && nextBase != null) {

output += simpOrComp.toString() + nextBase.toString();

} else if (simpOrComp != null) {

output += simpOrComp.toString();

}

return output;

}

}