cmd/lncli: move commands and export

We want to export some of our CLI code to re-use in other projects. But
in Golang you cannot import code from a `main` package.
So we need to move the actual code into its own package and only have
the `func main()` in the `main` package.

cmd/commands/commands_test.go

@@ -0,0 +1,201 @@
+package commands
+
+import (
+	"encoding/hex"
+	"fmt"
+	"math"
+	"strconv"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+// TestParseChanPoint tests parseChanPoint with various
+// valid and invalid input values and verifies the output.
+func TestParseChanPoint(t *testing.T) {
+	testCases := []struct {
+		channelPoinStr    string
+		channelPointIsNil bool
+		outputIndex       uint32
+		err               error
+	}{
+		{
+			"24581424081379576b4a7580ace91db10925d996a2a8d45c8034" +
+				"3a5a467dc0bc:0",
+			false,
+			0,
+			nil,
+		}, {
+			"24581424081379576b4a7580ace91db10925d996a2a8d45c8034" +
+				"3a5a467dc0bc:4",
+			false,
+			4,
+			nil,
+		}, {
+			":",
+			true,
+			0,
+			errBadChanPoint,
+		}, {
+			":0",
+			true,
+			0,
+			errBadChanPoint,
+		}, {
+			"24581424081379576b4a7580ace91db10925d996a2a8d45c8034" +
+				"3a5a467dc0bc:",
+			true,
+			0,
+			errBadChanPoint,
+		}, {
+			"24581424081379576b4a7580ace91db10925d996a2a8d45c8034" +
+				"3a5a467dc0bc:string",
+			true,
+			0,
+			strconv.ErrSyntax,
+		}, {
+			"not_hex:0",
+			true,
+			0,
+			hex.InvalidByteError('n'),
+		},
+	}
+	for _, tc := range testCases {
+		cp, err := parseChanPoint(tc.channelPoinStr)
+		require.ErrorIs(t, err, tc.err)
+
+		require.Equal(t, tc.channelPointIsNil, cp == nil)
+		if !tc.channelPointIsNil {
+			require.Equal(t, tc.outputIndex, cp.OutputIndex)
+		}
+	}
+}
+
+// TestParseTimeLockDelta tests parseTimeLockDelta with various
+// valid and invalid input values and verifies the output.
+func TestParseTimeLockDelta(t *testing.T) {
+	t.Parallel()
+	testCases := []struct {
+		timeLockDeltaStr      string
+		expectedTimeLockDelta uint16
+		expectErr             bool
+		expectedErrContent    string
+	}{
+		{
+			timeLockDeltaStr: "-1",
+			expectErr:        true,
+			expectedErrContent: fmt.Sprintf(
+				"failed to parse time_lock_delta: %d "+
+					"to uint64", -1,
+			),
+		},
+		{
+			timeLockDeltaStr: "0",
+		},
+		{
+			timeLockDeltaStr:      "3",
+			expectedTimeLockDelta: 3,
+		},
+		{
+			timeLockDeltaStr: strconv.FormatUint(
+				uint64(math.MaxUint16), 10,
+			),
+			expectedTimeLockDelta: math.MaxUint16,
+		},
+		{
+			timeLockDeltaStr: "18446744073709551616",
+			expectErr:        true,
+			expectedErrContent: fmt.Sprint(
+				"failed to parse time_lock_delta:" +
+					" 18446744073709551616 to uint64"),
+		},
+	}
+	for _, tc := range testCases {
+		timeLockDelta, err := parseTimeLockDelta(tc.timeLockDeltaStr)
+		require.Equal(t, tc.expectedTimeLockDelta, timeLockDelta)
+		if tc.expectErr {
+			require.ErrorContains(t, err, tc.expectedErrContent)
+		} else {
+			require.NoError(t, err)
+		}
+	}
+}
+
+// TestReplaceCustomData tests that hex encoded custom data can be formatted as
+// JSON in the console output.
+func TestReplaceCustomData(t *testing.T) {
+	t.Parallel()
+
+	testCases := []struct {
+		name        string
+		data        string
+		replaceData string
+		expected    string
+		expectedErr string
+	}{
+		{
+			name:     "no replacement necessary",
+			data:     "foo",
+			expected: "foo",
+		},
+		{
+			name: "valid json with replacement",
+			data: "{\"foo\":\"bar\",\"custom_channel_data\":\"" +
+				hex.EncodeToString([]byte(
+					"{\"bar\":\"baz\"}",
+				)) + "\"}",
+			expected: `{
+    "foo": "bar",
+    "custom_channel_data": {
+        "bar": "baz"
+    }
+}`,
+		},
+		{
+			name: "valid json with replacement and space",
+			data: "{\"foo\":\"bar\",\"custom_channel_data\": \"" +
+				hex.EncodeToString([]byte(
+					"{\"bar\":\"baz\"}",
+				)) + "\"}",
+			expected: `{
+    "foo": "bar",
+    "custom_channel_data": {
+        "bar": "baz"
+    }
+}`,
+		},
+		{
+			name: "doesn't match pattern, returned identical",
+			data: "this ain't even json, and no custom data " +
+				"either",
+			expected: "this ain't even json, and no custom data " +
+				"either",
+		},
+		{
+			name: "invalid json",
+			data: "this ain't json, " +
+				"\"custom_channel_data\":\"a\"",
+			expectedErr: "invalid character 'h' in literal true",
+		},
+		{
+			name:     "valid json, invalid hex, just formatted",
+			data:     "{\"custom_channel_data\":\"f\"}",
+			expected: "{\n    \"custom_channel_data\": \"f\"\n}",
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			result, err := replaceCustomData([]byte(tc.data))
+
+			if tc.expectedErr != "" {
+				require.ErrorContains(t, err, tc.expectedErr)
+				return
+			}
+
+			require.NoError(t, err)
+
+			require.Equal(t, tc.expected, string(result))
+		})
+	}
+}