Merge branch 'feature/cleanup-file-specific-history'

Author: markusressel

internal/ui/dialog/diff.go

@@ -0,0 +1,74 @@
+package dialog
+
+import (
+	"os"
+	"os/exec"
+	"strings"
+)
+
+const (
+	DiffBinPath = "/usr/bin/diff"
+)
+
+// DiffBinExists checks if the diff binary is available on the system.
+func DiffBinExists() bool {
+	_, err := exec.LookPath(DiffBinPath)
+	return err == nil
+}
+
+// RunDiff executes the system diff command on two files and returns the output.
+func RunDiff(oldPath, newPath string) (string, error) {
+	output, err := exec.Command(
+		DiffBinPath,
+		"-U", "3",
+		oldPath,
+		newPath,
+	).Output()
+	if err != nil && err.Error() != "exit status 1" {
+		return "", err
+	}
+	return string(output), nil
+}
+
+// IsBinaryFile checks if a file contains null bytes, indicating it is binary.
+func IsBinaryFile(path string) bool {
+	if path == DevNull {
+		return false
+	}
+	f, err := os.Open(path)
+	if err != nil {
+		return false
+	}
+	defer f.Close()
+
+	buf := make([]byte, 512)
+	n, _ := f.Read(buf)
+	for i := 0; i < n; i++ {
+		if buf[i] == 0 {
+			return true
+		}
+	}
+	return false
+}
+
+// FormatDiffText highlights diff additions (green) and deletions (red) with tview color tags.
+// If filterHeaders is true, it removes diff unified header lines (--- and +++).
+func FormatDiffText(diffText string, filterHeaders bool) string {
+	diffTextLines := strings.Split(diffText, "\n")
+	var resultLines []string
+	for _, line := range diffTextLines {
+		if filterHeaders {
+			if len(line) >= 4 && (strings.HasPrefix(line, "---") || strings.HasPrefix(line, "+++")) && (line[3] == ' ' || line[3] == '\t') {
+				continue
+			}
+		}
+		if strings.HasPrefix(line, "+") {
+			resultLines = append(resultLines, `[green]`+line+`[white]`)
+		} else if strings.HasPrefix(line, "-") {
+			resultLines = append(resultLines, `[red]`+line+`[white]`)
+		} else {
+			resultLines = append(resultLines, line)
+		}
+	}
+	return strings.Join(resultLines, "\n")
+}

internal/ui/dialog/diff_test.go

@@ -0,0 +1,52 @@
+package dialog
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestIsBinaryFile(t *testing.T) {
+	tempDir := t.TempDir()
+
+	// Text file
+	textFile := filepath.Join(tempDir, "text.txt")
+	err := os.WriteFile(textFile, []byte("Hello world, this is a plain text file."), 0644)
+	assert.NoError(t, err)
+	assert.False(t, IsBinaryFile(textFile))
+
+	// Binary file (contains null byte)
+	binFile := filepath.Join(tempDir, "binary.bin")
+	err = os.WriteFile(binFile, []byte{0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x00, 0x57, 0x6f, 0x72, 0x6c, 0x64}, 0644)
+	assert.NoError(t, err)
+	assert.True(t, IsBinaryFile(binFile))
+
+	// Non-existent file
+	assert.False(t, IsBinaryFile(filepath.Join(tempDir, "does-not-exist")))
+	assert.False(t, IsBinaryFile(DevNull))
+}
+
+func TestFormatDiffText(t *testing.T) {
+	diffInput := `--- old.txt
++++ new.txt
+@@ -1,3 +1,3 @@
+-Hello
++World
+ Unchanged`
+
+	// Test without filtering headers
+	outNoFilter := FormatDiffText(diffInput, false)
+	assert.Contains(t, outNoFilter, "[red]-Hello[white]")
+	assert.Contains(t, outNoFilter, "[green]+World[white]")
+	assert.Contains(t, outNoFilter, "--- old.txt")
+	assert.Contains(t, outNoFilter, "+++ new.txt")
+
+	// Test with filtering headers
+	outWithFilter := FormatDiffText(diffInput, true)
+	assert.Contains(t, outWithFilter, "[red]-Hello[white]")
+	assert.Contains(t, outWithFilter, "[green]+World[white]")
+	assert.NotContains(t, outWithFilter, "--- old.txt")
+	assert.NotContains(t, outWithFilter, "+++ new.txt")
+}

internal/ui/dialog/file_action_dialog.go

@@ -2,7 +2,6 @@ package dialog
 
 import (
 	"fmt"
-	"os/exec"
 	"slices"
 	"zfs-file-history/internal/data"
 	"zfs-file-history/internal/ui/localization"
@@ -95,11 +94,3 @@ func buildFileDialogOptions(file *data.FileBrowserEntry, diffBinAvailable bool)
 
 	return ensureDialogCloseIsLast(dialogOptions)
 }
-
-func DiffBinExists() bool {
-	_, err := exec.LookPath(DiffBinPath)
-	if err != nil {
-		return false
-	}
-	return true
-}

internal/ui/dialog/file_diff_dialog.go

@@ -1,8 +1,6 @@
 package dialog
 
 import (
-	"os/exec"
-	"strings"
 	"zfs-file-history/internal/data"
 	"zfs-file-history/internal/ui/util"
 
@@ -11,8 +9,6 @@ import (
 )
 
 const (
-	DiffBinPath = "/usr/bin/diff"
-
 	FileDiffDialogPage util.Page = "FileDiffDialog"
 )
 
@@ -43,28 +39,19 @@ func (d *FileDiffDialog) createLayout() {
 	realFilePath := d.file.RealFile.Path
 	snapshotFilePath := d.snapshot.Snapshot.GetSnapshotPath(d.file.RealFile.Path)
 
-	output, err := exec.Command(
-		DiffBinPath,
-		"-U", "3",
-		snapshotFilePath,
-		realFilePath,
-	).Output()
-	diffText := string(output)
-	if err != nil && err.Error() != "exit status 1" {
-		diffText = "error calculating diff: " + err.Error()
-	}
-
-	diffTextLines := strings.Split(diffText, "\n")
-	for i := 0; i < len(diffTextLines); i++ {
-		line := diffTextLines[i]
-		if strings.HasPrefix(line, "+") {
-			diffTextLines[i] = `[green]` + line + `[white]`
-		}
-		if strings.HasPrefix(line, "-") {
-			diffTextLines[i] = `[red]` + line + `[white]`
+	var diffText string
+	isBinary := IsBinaryFile(snapshotFilePath) || IsBinaryFile(realFilePath)
+	if isBinary {
+		diffText = "Binary files differ, content preview not available."
+	} else {
+		var err error
+		diffText, err = RunDiff(snapshotFilePath, realFilePath)
+		if err != nil {
+			diffText = "error calculating diff: " + err.Error()
+		} else {
+			diffText = FormatDiffText(diffText, false)
 		}
 	}
-	diffText = strings.Join(diffTextLines, "\n")
 
 	textDescriptionView := tview.NewTextView().
 		SetDynamicColors(true).