import java.util.Vector;
import java.util.Arrays;
import java.util.regex.Pattern;
import java.io.*;

public class Interpreter {

    String filename;

    public Interpreter(String filename) {
        this.filename = filename;
    }
    /*Global vars*/
    private static int errors = 0;
    /*Reserved words list*/
    final String[] RESERVED_WORDS = {"add","sub","mul","div","exp","mod","eq","ne","ge","gt","le","lt","AND","OR","NOT"};
    final String[] DATA_TYPES = {"SHORT", "FLOAT", "BOOL", "STRING"};
    /*EBNF Rules*/
    /*MAIN*/
    public static void main(String[] args) throws Exception { //args[0] is our file
        if(args.length < 1) {
            System.out.println("No file specified");
            System.out.println("USAGE: Interpreter <filename.ext>");
        }
        else {
            Interpreter i = new Interpreter(args[0]);
            if(i.checkSyntax()) System.out.println("Starting program...");
            else System.out.println("Interpretation Failed... found "+errors+" error(s)");
        }
    }

    public boolean checkSyntax() throws Exception{
        FileInputStream fis = new FileInputStream(filename);
        DataInputStream dis = new DataInputStream(fis);
        BufferedReader br = new BufferedReader(new InputStreamReader(dis));
        String strLine;
        String[] split;
        int lineNumber = 1;
        while((strLine = br.readLine()) != null) {
            if(strLine.charAt(0) != '#') { //if it is not a comment
                split = strLine.split(" ");
                //System.out.println(Arrays.toString(split));
                for(String s : RESERVED_WORDS) {
                    if(s.equalsIgnoreCase(split[0])) {
                        System.out.println("[LINE "+lineNumber+"]: Illegal start of expression");
                        System.out.println(">>> "+strLine);
                        errors++;
                    }
                }
                for(String s : DATA_TYPES) {
                    if(s.equalsIgnoreCase(split[0])) {
                        System.out.println("[LINE "+lineNumber+"]: Variable declatarion without a name");
                        System.out.println(">>> "+strLine);
                        errors++;
                    }
                }
            }
            lineNumber++;
        }
        if(errors > 0) return false;
        else return true;
    }

}