package hu.blogspot.visitcatalunya.calculadora;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;


public class MainActivity extends AppCompatActivity {

    public double total = 0;  // number shown in the result textView
    public boolean comma = false;
    public boolean editNum = true;
    public int sign = 1;
    public int decimal = 0;
    public double num1 = 0;
    public double num2 = 0;
    public int lastButton = 1;
    public int operation = 0;
    public int saveOperation = 0;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    /*

     */
    public void Display(View v) {
        TextView result = (TextView) findViewById(R.id.result);
        result.setText(String.valueOf(total));
    }

    public void delete(View v) {
        total = 0;
        decimal = 0;
        comma = false;
        editNum = true;
        sign = 1;
        num1 = 0;
        num2 = 0;
        Display(v);
        lastButton = 1;
        saveOperation = 0;
        operation = 0;
    }

    public void dot(View v) {
        comma = true;
        lastButton = 18;
    }

    public void plusMinus(View v) {
        total = -total;
        sign *= -1;
        Display(v);
        lastButton = 19;
    }

    // ===========================================================================
    public void calculate(View v) {
        if (lastButton == 20) {
            operation = saveOperation;
        } else if (lastButton == 2) {
            if (operation == 1 || operation == 2) {
                num2 = total * num1 / 100;
            } else {
                num2 = total / 100;
            }
        } else {
            num2 = total;
        }

        if (operation == 1) {
            total = num1 + num2;
            num1 = total;

        } else if (operation == 2) {
            total = num1 - num2;
            num1 = total;
        } else if (operation == 3) {
            total = num1 * num2;
            num1 = total;
        } else if (operation == 4) {
            total = num1 / num2;
            num1 = total;
        }

        Display(v);

        editNum = false;
        lastButton = 20;
        comma = false;
        decimal = 0;
        saveOperation = operation;
        operation = 0;

    }


    public void sum(View v) {

        if (operation == 0) {
            num1 = total;
            total = 0;
            operation = 1;
        } else if (lastButton == 4 || lastButton == 8 || lastButton == 12 || lastButton == 16 || lastButton == 20) { //changes operation with no more effects
            operation = 1;
        } else {
            num2 = total;
            calculate(v);
            operation = 1;
        }
        decimal = 0;
        comma = false;

        lastButton = 16;

    }

    public void res(View v) {
        if (operation == 0) { //
            num1 = total;
            total = 0;
            operation = 2;
        } else if (lastButton == 4 || lastButton == 8 || lastButton == 12 || lastButton == 16 || lastButton == 20) { //changes operation with no more effects
            operation = 1;
        } else {
            num2 = total;
            calculate(v);
            operation = 2;
        }

        decimal = 0;
        comma = false;


        lastButton = 12;
    }


    public void per(View v) {
        if (operation == 0) { //
            num1 = total;
            total = 0;
            operation = 3;
        } else if (lastButton == 4 || lastButton == 8 || lastButton == 12 || lastButton == 16 || lastButton == 20) { //changes operation with no more effects
            operation = 3;
        } else {
            num2 = total;
            calculate(v);
            operation = 3;
        }

        decimal = 0;
        comma = false;

        lastButton = 8;
    }

    public void div(View v) {
        if (operation == 0) {
            num1 = total;
            total = 0;
            operation = 4;
        } else if (lastButton == 4 || lastButton == 8 || lastButton == 12 || lastButton == 16 || lastButton == 20) { //changes operation with no more effects
            operation = 4;
        } else {
            num2 = total;
            calculate(v);
            operation = 4;
        }

        decimal = 0;
        lastButton = 4;
    }

    public void percent(View v) {
        if (lastButton != 2) {
            lastButton = 2;
            calculate(v);


        }
    }

    public void sqrtRoot(View v) {
        if (total < 0) {
            Toast.makeText(MainActivity.this, "Negative number, use +/- before", Toast.LENGTH_SHORT).show();
        } else {
            total = Math.sqrt(total);
            Display(v);
        }
        editNum = false;
        lastButton = 3;

    }

    //00000000000000000000000000000000000000000000000000000000000
    public void set0(View v) {
        if (lastButton == 20 || lastButton <= 3) {
            delete(v);
        }
        if (editNum) {

            if (!comma) {
                total = total * 10;
            } else {
                decimal++;
            }
        } else {
            total = 0;
            decimal = 0;
            editNum = true;
            sign = 1;
        }
        Display(v);
        lastButton = 17;


    }

    //11111111111111111111111111111111111111111111111111111111
    public void set1(View v) {
        if (lastButton == 20 || lastButton <= 3) {
            total = 0;
        }
        if (editNum) {

            if (!comma) {
                total = total * 10 + sign;
            } else {
                decimal++;
                total = total + sign / (Math.pow(10, decimal));
            }
        } else {
            total = 1;
            decimal = 0;
            sign = 1;
            editNum = true;
        }
        Display(v);
        lastButton = 13;


    }

    //222222222222222222222222222222222222222222222222222222222
    public void set2(View v) {
        if (lastButton == 20 || lastButton <= 3) {
            total = 0;
        }
        if (editNum) {

            if (!comma) {
                total = total * 10 + 2 * sign;
            } else {
                decimal++;
                total = total + 2 * sign / (Math.pow(10, decimal));
            }
        } else {
            total = 2;
            decimal = 0;
            sign = 1;
            editNum = true;
        }
        Display(v);
        lastButton = 14;

    }

    public void set3(View v) {
        if (lastButton == 20 || lastButton <= 3) {
            total = 0;
        }
        if (editNum) {

            if (!comma) {
                total = total * 10 + 3 * sign;
            } else {
                decimal++;
                total = total + 3 * sign / (Math.pow(10, decimal));
            }
        } else {
            total = 3;
            decimal = 0;
            sign = 1;
            editNum = true;
        }
        Display(v);
        lastButton = 15;

    }

    public void set4(View v) {
        if (editNum) {

            if (!comma) {
                total = total * 10 + 4 * sign;
            } else {
                decimal++;
                total = total + 4 * sign / (Math.pow(10, decimal));
            }
        } else {
            total = 4;
            decimal = 0;
            sign = 1;
            editNum = true;
        }
        Display(v);
        lastButton = 9;

    }

    public void set5(View v) {
        if (editNum) {

            if (!comma) {
                total = total * 10 + 5 * sign;
            } else {
                decimal++;
                total = total + 5 * sign / (Math.pow(10, decimal));
            }
        } else {
            total = 5;
            decimal = 0;
            sign = 1;
            editNum = true;
        }
        Display(v);
        lastButton = 10;

    }

    public void set6(View v) {
        if (editNum) {

            if (!comma) {
                total = total * 10 + 6 * sign;
            } else {
                decimal++;
                total = total + 6 * sign / (Math.pow(10, decimal));
            }
        } else {
            total = 6;
            decimal = 0;
            sign = 1;
            editNum = true;
        }
        Display(v);
        lastButton = 11;

    }

    public void set7(View v) {
        if (editNum) {

            if (!comma) {
                total = total * 10 + 7 * sign;
            } else {
                decimal++;
                total = total + 7 * sign / (Math.pow(10, decimal));
            }
        } else {
            total = 7;
            decimal = 0;
            sign = 1;
            editNum = true;
        }
        Display(v);
        lastButton = 5;

    }

    public void set8(View v) {
        if (editNum) {

            if (!comma) {
                total = total * 10 + 8 * sign;
            } else {
                decimal++;
                total = total + 8 * sign / (Math.pow(10, decimal));
            }
        } else {
            total = 8;
            decimal = 0;
            sign = 1;
            editNum = true;
        }
        Display(v);
        lastButton = 6;

    }

    public void set9(View v) {
        if (editNum) {

            if (!comma) {
                total = total * 10 + 9 * sign;
            } else {
                decimal++;
                total = total + 9 * sign / (Math.pow(10, decimal));
            }
        } else {
            total = 9;
            decimal = 0;
            sign = 1;
            editNum = true;
        }
        Display(v);
        lastButton = 7;

    }


}