package cp3000

import (
	"bytes"
	"fmt"
	"testing"

	"github.com/stretchr/testify/assert"
)

func TestCalcChecksum(t *testing.T) {
	var buffer bytes.Buffer
	fmt.Fprintf(&buffer, `$00`)
	assert.Equal(t, uint8(0x00), calcChecksum(buffer), `Expected checksum of $00 equals to 00`)

	buffer.Reset()
	fmt.Fprintf(&buffer, `$SENDSMS,"0655866244","I still know what you did last summer"`)
	assert.Equal(t, uint8(0x5C), calcChecksum(buffer), `Expected checksum of \"$SENDSMS,"0655866244","I still know what you
				did last summer"\" equals to 5C`)

	buffer.Reset()
	fmt.Fprintf(&buffer, `$SENDSMS,"I still know what you did last summer","0629584133"`)
	assert.Equal(t, uint8(0x55), calcChecksum(buffer), `Expected checksum of \"$SENDSMS,"0629584133","I still know what you
				did last summer"\" equals to 55.`)

	buffer.Reset()
	fmt.Fprintf(&buffer, `$SENDSMS,"0629584133","Rik is cool"`)
	assert.Equal(t, uint8(0x11), calcChecksum(buffer), `Expected checksum of \"$SENDSMS,"0629584133","Rik is cool"\"
				equals to 11.`)

	buffer.Reset()
	fmt.Fprintf(&buffer, `SENDSMS,"0629584133","Rik is cool"*`)
	assert.Equal(t, uint8(0x11), calcChecksum(buffer), `Expected checksum of \"SENDSMS,"0629584133","Rik is cool*"\"
	 			equals to 11.`)

	buffer.Reset()
	fmt.Fprintf(&buffer, `SENDSMS,"0629584133","Rik i*s cool"*`)
	assert.Equal(t, uint8(0x3b), calcChecksum(buffer), `Expected checksum of \"SENDSMS,"0629584133","Rik i*s cool*"\"
	 			equals to 3b.`)

}