package miniJava;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.InputStream;

import miniJava.AbstractSyntaxTrees.AST;

import miniJava.AbstractSyntaxTrees.ASTDisplay;

import miniJava.CodeGenerator.CodeGenerator;

import miniJava.ContextualAnalyzer.Identification;

import miniJava.ContextualAnalyzer.TypeChecking;

import miniJava.SyntacticAnalyzer.Parser;

import miniJava.SyntacticAnalyzer.Scanner;

public class Compiler {

enum CompilerStage {

PARSER(0), // PA1, PA2

TYPE_CHECKING(1), // PA3

CODE_GENERATION(2); // PA4, PA5

private int value;

CompilerStage(final int initValue) {

value = initValue;

}

public int getValue() {

return value;

}

};

public static void checkFailure(ErrorReporter reporter, String stepName) {

if (reporter.hasErrors()) {

System.out.println("INVALID program after " + stepName);

// return code for invalid input

System.exit(4);

}

}

public static void main(String[] args) {

// Use to test different portions of the compiler

CompilerStage finalStage = CompilerStage.CODE_GENERATION;

if (args.length > 1) {

switch (args[1]) {

case "PARSER":

finalStage = CompilerStage.PARSER;

break;

case "TYPE CHECKING":

finalStage = CompilerStage.TYPE_CHECKING;

break;

case "CODE GENERATION":

finalStage = CompilerStage.CODE_GENERATION;

break;

}

}

InputStream inputStream = null;

try {

inputStream = new FileInputStream(args[0]);

} catch (FileNotFoundException e) {

System.out.println("Input file " + args[0] + " not found");

System.exit(3);

}

ErrorReporter reporter = new ErrorReporter();

Scanner scanner = new Scanner(inputStream, reporter);

Parser parser = new Parser(scanner, reporter);

ASTDisplay display = new ASTDisplay();

Identification identifier = new Identification(reporter);

// IdentificationVerifier verifier = new IdentificationVerifier();

TypeChecking typeChecker = new TypeChecking(identifier, reporter);

AST theAST = null;

try {

if (finalStage.getValue() >= CompilerStage.PARSER.getValue()) {

theAST = parser.parse();

checkFailure(reporter, "parsing");

// Needed for pa2_tests

if (finalStage == CompilerStage.PARSER)

display.showTree(theAST);

}

if (finalStage.getValue() >= CompilerStage.TYPE_CHECKING.getValue()) {

identifier.linkDeclarationsAndReferences(theAST);

// verifier.verifyIdentification(theAST);

checkFailure(reporter, "identification");

typeChecker.typeCheck(theAST);

checkFailure(reporter, "type checking");

}

if (finalStage.getValue() >= CompilerStage.CODE_GENERATION.getValue()) {

CodeGenerator generator = new CodeGenerator(reporter);

generator.generateCode(theAST, args[0]);

checkFailure(reporter, "code generation");

}

System.out.println("valid program");

// return code for valid input

System.exit(0);

} catch (Exception e) {

reporter.reportError("*** line " + scanner.currentPosition().lineNumber + ": compiler failed with " + e);

// return code for invalid input

System.exit(4);

}

}

}