package encoding

import (
	"bytes"
	"testing"
)

func TestGSM7EncodeSimpleASCIIString(t *testing.T) {
	coder := &GSM7Coder{}
	var buf bytes.Buffer
	input := "Sunshine"

	expected := []byte{0b11010011, 0b10111010, 0b01111011, 0b10001110, 0b01001110, 0b10111011, 0b11001011}
	err := coder.Encode(input, &buf)

	if err != nil {
		t.Errorf("Expected no error, but got %v", err)
	}

	if !bytes.Equal(buf.Bytes(), expected) {
		t.Errorf("Expected %v, but got %v", expected, buf.Bytes())
	}
}

func TestGSM7EncodeComplexASCIIString(t *testing.T) {
	coder := &GSM7Coder{}
	var buf bytes.Buffer
	input := "Golden rays play, Chasing night away."

	expected := []byte{0b11000111, 0b00110111, 0b10011011, 0b01011100, 0b01110110, 0b10000011, 0b11100100, 0b11100001, 0b11111100, 0b00011100, 0b00000100, 0b01100111, 0b10000111, 0b11110011, 0b00101100, 0b11010000, 0b00010000, 0b00011101, 0b10011110, 0b10100111, 0b11011101, 0b01100111, 0b10010000, 0b00111011, 0b01111101, 0b01000110, 0b11010011, 0b01000001, 0b11100001, 0b01111011, 0b00111000, 0b11101111, 0b00000010}
	err := coder.Encode(input, &buf)

	if err != nil {
		t.Errorf("Expected no error, but got %v", err)
	}

	if !bytes.Equal(buf.Bytes(), expected) {
		t.Errorf("Expected %v, but got %v", expected, buf.Bytes())
	}
}

func TestGSM7EncodeEmptyString(t *testing.T) {
	coder := &GSM7Coder{}
	var buf bytes.Buffer
	input := ""

	expected := []byte{}
	err := coder.Encode(input, &buf)

	if err != nil {
		t.Errorf("Expected no error, but got %v", err)
	}

	if !bytes.Equal(buf.Bytes(), expected) {
		t.Errorf("Expected %v, but got %v", expected, buf.Bytes())
	}
}

func TestGSM7DecodeSimpleASCIIString(t *testing.T) {
	coder := &GSM7Coder{}
	var buf bytes.Buffer
	input := []byte{0b11010011, 0b10111010, 0b01111011, 0b10001110, 0b01001110, 0b10111011, 0b11001011}

	expected := "Sunshine"
	buf.Write(input)
	output, err := coder.Decode(&buf)

	if err != nil {
		t.Errorf("Expected no error, but got %v", err)
	}

	if output != expected {
		t.Errorf("Expected %v, but got %v", expected, output)
	}
}

func TestGSM7DecodeComplexASCIIString(t *testing.T) {
	coder := &GSM7Coder{}
	var buf bytes.Buffer
	input := []byte{0b11010011, 0b10111010, 0b01111011, 0b10001110, 0b01001110, 0b10111011, 0b11001011}

	expected := "Golden rays play, Chasing night away."
	buf.Write(input)
	output, err := coder.Decode(&buf)

	if err != nil {
		t.Errorf("Expected no error, but got %v", err)
	}

	if output != expected {
		t.Errorf("Expected %v, but got %v", expected, output)
	}
}

func TestGSM7DecodeEmptyString(t *testing.T) {
	coder := &GSM7Coder{}
	buf := bytes.NewBuffer([]byte{})

	expected := ""
	output, err := coder.Decode(buf)

	if err != nil {
		t.Errorf("Expected no error, but got %v", err)
	}

	if output != expected {
		t.Errorf("Expected %v, but got %v", expected, output)
	}
}