package command_test

import (
	"testing"

	"git.netflux.io/rob/solar-toolkit/command"
	"github.com/stretchr/testify/require"
)

func TestModbusValidateResponse(t *testing.T) {
	validResponse := []byte{170, 85, 247, 3, 250, 22, 7, 15, 17, 46, 24, 11, 243, 0, 83, 0, 0, 9, 243, 9, 53, 0, 41, 0, 0, 3, 198, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 0, 0, 2, 2, 9, 114, 0, 144, 19, 136, 0, 0, 13, 182, 255, 255, 255, 255, 255, 255, 127, 255, 255, 255, 255, 255, 255, 255, 255, 255, 127, 255, 255, 255, 0, 1, 0, 0, 13, 182, 0, 0, 11, 153, 127, 255, 255, 255, 255, 255, 255, 255, 9, 112, 0, 5, 19, 136, 0, 1, 0, 0, 0, 0, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 0, 0, 2, 29, 128, 0, 0, 0, 128, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 29, 0, 2, 2, 169, 127, 255, 2, 20, 1, 0, 14, 181, 255, 255, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 33, 0, 1, 255, 255, 0, 0, 0, 0, 0, 0, 34, 145, 0, 0, 1, 100, 0, 0, 34, 139, 0, 0, 1, 52, 1, 96, 0, 0, 0, 0, 0, 0, 0, 0, 13, 73, 0, 126, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 64, 0, 0, 0, 2, 8, 64, 71, 0, 3, 0, 0, 255, 255, 147, 214}
	validResponseWithExtraBytes := []byte{170, 85, 247, 3, 250, 22, 7, 15, 17, 46, 24, 11, 243, 0, 83, 0, 0, 9, 243, 9, 53, 0, 41, 0, 0, 3, 198, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 0, 0, 2, 2, 9, 114, 0, 144, 19, 136, 0, 0, 13, 182, 255, 255, 255, 255, 255, 255, 127, 255, 255, 255, 255, 255, 255, 255, 255, 255, 127, 255, 255, 255, 0, 1, 0, 0, 13, 182, 0, 0, 11, 153, 127, 255, 255, 255, 255, 255, 255, 255, 9, 112, 0, 5, 19, 136, 0, 1, 0, 0, 0, 0, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 0, 0, 2, 29, 128, 0, 0, 0, 128, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 29, 0, 2, 2, 169, 127, 255, 2, 20, 1, 0, 14, 181, 255, 255, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 33, 0, 1, 255, 255, 0, 0, 0, 0, 0, 0, 34, 145, 0, 0, 1, 100, 0, 0, 34, 139, 0, 0, 1, 52, 1, 96, 0, 0, 0, 0, 0, 0, 0, 0, 13, 73, 0, 126, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 64, 0, 0, 0, 2, 8, 64, 71, 0, 3, 0, 0, 255, 255, 147, 214, 1, 2, 3}
	invalidReadLengthResponse := []byte{170, 85, 247, 3, 250, 22, 7, 15, 17, 46, 24, 243, 0, 83, 0, 0, 9, 243, 9, 53, 0, 41, 0, 0, 3, 198, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 0, 0, 2, 2, 9, 114, 0, 144, 19, 136, 0, 0, 13, 182, 255, 255, 255, 255, 255, 255, 127, 255, 255, 255, 255, 255, 255, 255, 255, 255, 127, 255, 255, 255, 0, 1, 0, 0, 13, 182, 0, 0, 11, 153, 127, 255, 255, 255, 255, 255, 255, 255, 9, 112, 0, 5, 19, 136, 0, 1, 0, 0, 0, 0, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 0, 0, 2, 29, 128, 0, 0, 0, 128, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 29, 0, 2, 2, 169, 127, 255, 2, 20, 1, 0, 14, 181, 255, 255, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 33, 0, 1, 255, 255, 0, 0, 0, 0, 0, 0, 34, 145, 0, 0, 1, 100, 0, 0, 34, 139, 0, 0, 1, 52, 1, 96, 0, 0, 0, 0, 0, 0, 0, 0, 13, 73, 0, 126, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 64, 0, 0, 0, 2, 8, 64, 71, 0, 3, 0, 0, 255, 255, 147, 213}
	invalidChecksumResponse := []byte{170, 85, 247, 3, 250, 22, 7, 15, 17, 46, 24, 11, 243, 0, 83, 0, 0, 9, 243, 9, 53, 0, 41, 0, 0, 3, 198, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 0, 0, 2, 2, 9, 114, 0, 144, 19, 136, 0, 0, 13, 182, 255, 255, 255, 255, 255, 255, 127, 255, 255, 255, 255, 255, 255, 255, 255, 255, 127, 255, 255, 255, 0, 1, 0, 0, 13, 182, 0, 0, 11, 153, 127, 255, 255, 255, 255, 255, 255, 255, 9, 112, 0, 5, 19, 136, 0, 1, 0, 0, 0, 0, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 0, 0, 2, 29, 128, 0, 0, 0, 128, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 29, 0, 2, 2, 169, 127, 255, 2, 20, 1, 0, 14, 181, 255, 255, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 33, 0, 1, 255, 255, 0, 0, 0, 0, 0, 0, 34, 145, 0, 0, 1, 100, 0, 0, 34, 139, 0, 0, 1, 52, 1, 96, 0, 0, 0, 0, 0, 0, 0, 0, 13, 73, 0, 126, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 64, 0, 0, 0, 2, 8, 64, 71, 0, 3, 0, 0, 255, 255, 147, 213}
	failureCodeResponse := []byte{170, 85, 0, 0, 1, 176}

	testCases := []struct {
		name    string
		resp    []byte
		wantErr string
	}{
		{
			name:    "empty response",
			wantErr: "invalid response: response too short",
		},
		{
			name:    "invalid read length",
			resp:    invalidReadLengthResponse,
			wantErr: "invalid read length: expected 257, got 256",
		},
		{
			name:    "invalid checksum",
			resp:    invalidChecksumResponse,
			wantErr: "invalid CRC-16: want `D693`, got `D593`",
		},
		{
			name:    "failure code rcvd",
			resp:    failureCodeResponse,
			wantErr: "command failed with code: 1, error: FailureCodeIllegalFunction",
		},
		{
			name: "valid response with extra bytes",
			resp: validResponseWithExtraBytes,
		},
		{
			name: "valid response",
			resp: validResponse,
		},
	}

	for _, tc := range testCases {
		t.Run(tc.name, func(t *testing.T) {
			cmd := command.NewModbus(command.ModbusCommandTypeRead, 0x891c, 0x007d)
			_, err := cmd.ValidateResponse(tc.resp)

			if tc.wantErr == "" {
				require.NoError(t, err)
			} else {
				require.EqualError(t, err, tc.wantErr)
			}
		})
	}
}