import java.util.ArrayList;
import java.util.List;



/*
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/**
 *
 * @author tymoteuszilczyszyn
 */
public class T1CodeGen implements Codegen {


    public static String concat(String s1, String s2) {
        return s1 + "\n" + s2;
    }

    @Override
    public String codegen(Program p) throws CodegenException {

        String output = "";
        output = "jal " + p.decls.get(0).id + "_entry";
        output = concat(output,"li $v0 10");
        output = concat(output,"syscall");

        for (int i=0;i<p.decls.size();i++) {
            output = concat(output,this.genDecl(p.decls.get(i)));
        }


        return output;
    }

    public String genExp (Exp e) {
        String output = "";

        if (e instanceof IntLiteral) {
            output = "li $a0 " + Integer.toString(((IntLiteral) e).n);

        } else if (e instanceof Variable) {

        } else if (e instanceof If) {

        } else if (e instanceof Binexp) {

        } else if (e instanceof Invoke) {

        }


        return output;
    }

    public String genDecl (Declaration d) {
        String output = "";
        int sizeAR = (0 + d.numOfArgs) * 4;

        output = d.id + "_entry:";
        output = concat(output,"move $fp $sp");
        output = concat(output,"sw $ra 0($sp)");
        output = concat(output,"addiu $sp $sp -4");
        output = concat(output,this.genExp(d.body));
        output = concat(output,"lw $ra 4($sp)");
        output = concat(output,"addiu $sp $sp " + Integer.toString(sizeAR));
        output = concat(output,"lw $fp 0($sp)");
        output = concat(output,"jr $ra");

        return output;
    }

    public static void main (String args[]) throws CodegenException {

        T1CodeGen t1 = new T1CodeGen();

        IntLiteral s = new IntLiteral(5);
        Declaration d = new Declaration("tymek1",2,s);
        List<Declaration> l = new ArrayList<Declaration>();
        l.add(d);

        Program p = new Program(l);

        System.out.println(t1.codegen(p));
    }

}