Feature/show file diff

Makefile

@@ -32,4 +32,4 @@ deploy: clean build
 
 clean:
 	go clean
-	rm ${OUTPUT_BIN}
+	rm -f ${OUTPUT_BIN}

go.mod

@@ -15,6 +15,7 @@ require (
 	github.com/oklog/run v1.1.0
 	github.com/pterm/pterm v0.12.79
 	github.com/rivo/tview v0.0.0-20240728114935-65571ae51e71
+	github.com/sergi/go-diff v1.2.0
 	github.com/spf13/cobra v1.8.1
 	github.com/spf13/viper v1.19.0
 	github.com/stretchr/testify v1.9.0

internal/ui/dialog/delete_file_dialog.go

@@ -37,8 +37,8 @@ func NewDeleteFileDialog(application *tview.Application, file *data.FileBrowserE
 func (d *DeleteFileDialog) createLayout() {
 	dialogTitle := " Delete File "
 
-	textDesctiption := fmt.Sprintf("Delete '%s'?", d.file.Name)
-	textDesctiptionView := tview.NewTextView().SetText(textDesctiption)
+	textDescription := fmt.Sprintf("Delete '%s'?", d.file.Name)
+	textDescriptionView := tview.NewTextView().SetText(textDescription)
 
 	optionTable := tview.NewTable()
 	optionTable.SetSelectable(true, false)
@@ -94,7 +94,7 @@ func (d *DeleteFileDialog) createLayout() {
 	}
 
 	dialogContent := tview.NewFlex().SetDirection(tview.FlexRow)
-	dialogContent.AddItem(textDesctiptionView, 0, 1, false)
+	dialogContent.AddItem(textDescriptionView, 0, 1, false)
 	dialogContent.AddItem(optionTable, 0, 1, true)
 
 	dialog := createModal(dialogTitle, dialogContent, 50, 6)

internal/ui/dialog/delete_snapshot_dialog.go

@@ -37,8 +37,8 @@ func NewDeleteSnapshotDialog(application *tview.Application, snapshot *data.Snap
 func (d *DeleteSnapshotDialog) createLayout() {
 	dialogTitle := " Destroy Snapshot "
 
-	textDesctiption := fmt.Sprintf("Destroy '%s'?", d.snapshot.Snapshot.Name)
-	textDesctiptionView := tview.NewTextView().SetText(textDesctiption)
+	textDescription := fmt.Sprintf("Destroy '%s'?", d.snapshot.Snapshot.Name)
+	textDescriptionView := tview.NewTextView().SetText(textDescription)
 
 	optionTable := tview.NewTable()
 	optionTable.SetSelectable(true, false)
@@ -92,7 +92,7 @@ func (d *DeleteSnapshotDialog) createLayout() {
 	}
 
 	dialogContent := tview.NewFlex().SetDirection(tview.FlexRow)
-	dialogContent.AddItem(textDesctiptionView, 0, 1, false)
+	dialogContent.AddItem(textDescriptionView, 0, 1, false)
 	dialogContent.AddItem(optionTable, 0, 1, true)
 
 	dialog := createModal(dialogTitle, dialogContent, 50, 6)

internal/ui/dialog/file_action_dialog.go

@@ -5,15 +5,18 @@ import (
 	"github.com/gdamore/tcell/v2"
 	"github.com/rivo/tview"
 	"golang.org/x/exp/slices"
+	"os/exec"
 	"zfs-file-history/internal/data"
+	"zfs-file-history/internal/data/diff_state"
 	"zfs-file-history/internal/ui/util"
 )
 
 const (
 	ActionDialog util.Page = "ActionDialog"
 
 	// recursively restores all files and folders top to bottom starting with the given entry
-	FileDialogRestoreFileActionId DialogActionId = iota
+	FileDialogShowDiffActionId DialogActionId = iota
+	FileDialogRestoreFileActionId
 	FileDialogRestoreRecursiveDialogActionId
 	FileDialogDeleteDialogActionId
 	FileDialogCreateSnapshotDialogActionId
@@ -41,8 +44,8 @@ func NewFileActionDialog(application *tview.Application, file *data.FileBrowserE
 func (d *FileActionDialog) createLayout() {
 	dialogTitle := " Select Action "
 
-	textDesctiption := fmt.Sprintf("What do you want to do with '%s'?", d.file.Name)
-	textDesctiptionView := tview.NewTextView().SetText(textDesctiption)
+	textDescription := fmt.Sprintf("What do you want to do with '%s'?", d.file.Name)
+	textDescriptionView := tview.NewTextView().SetText(textDescription)
 
 	optionTable := tview.NewTable()
 	optionTable.SetSelectable(true, false)
@@ -75,7 +78,13 @@ func (d *FileActionDialog) createLayout() {
 		}
 
 		if d.file.Type == data.File {
-			dialogOptions = slices.Insert(dialogOptions, 0, &DialogOption{
+			if DiffBinExists() && d.file.DiffState == diff_state.Modified {
+				dialogOptions = slices.Insert(dialogOptions, 0, &DialogOption{
+					Id:   FileDialogShowDiffActionId,
+					Name: fmt.Sprintf("Show diff"),
+				})
+			}
+			dialogOptions = slices.Insert(dialogOptions, 1, &DialogOption{
 				Id:   FileDialogRestoreFileActionId,
 				Name: fmt.Sprintf("Restore file"),
 			})
@@ -123,7 +132,7 @@ func (d *FileActionDialog) createLayout() {
 	}
 
 	dialogContent := tview.NewFlex().SetDirection(tview.FlexRow)
-	dialogContent.AddItem(textDesctiptionView, 0, 1, false)
+	dialogContent.AddItem(textDescriptionView, 0, 1, false)
 	dialogContent.AddItem(optionTable, 0, 1, true)
 
 	dialog := createModal(dialogTitle, dialogContent, 50, 15)
@@ -142,6 +151,14 @@ func (d *FileActionDialog) createLayout() {
 	d.layout = dialog
 }
 
+func DiffBinExists() bool {
+	_, err := exec.LookPath(DiffBinPath)
+	if err != nil {
+		return false
+	}
+	return true
+}
+
 func (d *FileActionDialog) GetName() string {
 	return string(ActionDialog)
 }
@@ -169,6 +186,8 @@ func (d *FileActionDialog) RestoreFile() {
 
 func (d *FileActionDialog) selectAction(option *DialogOption) {
 	switch option.Id {
+	case FileDialogShowDiffActionId:
+		d.ShowDiff()
 	case FileDialogRestoreFileActionId:
 		d.RestoreFile()
 	case FileDialogRestoreRecursiveDialogActionId:
@@ -202,3 +221,10 @@ func (d *FileActionDialog) CreateSnapshot() {
 		d.actionChannel <- FileDialogCreateSnapshotDialogActionId
 	}()
 }
+
+func (d *FileActionDialog) ShowDiff() {
+	go func() {
+		d.actionChannel <- DialogCloseActionId
+		d.actionChannel <- FileDialogShowDiffActionId
+	}()
+}

internal/ui/dialog/file_diff_dialog.go

@@ -0,0 +1,113 @@
+package dialog
+
+import (
+	"github.com/gdamore/tcell/v2"
+	"github.com/rivo/tview"
+	"os/exec"
+	"strings"
+	"zfs-file-history/internal/data"
+	"zfs-file-history/internal/ui/util"
+)
+
+const (
+	DiffBinPath = "/usr/bin/diff"
+
+	FileDiffDialogPage util.Page = "FileDiffDialog"
+)
+
+type FileDiffDialog struct {
+	application   *tview.Application
+	file          *data.FileBrowserEntry
+	snapshot      *data.SnapshotBrowserEntry
+	layout        *tview.Flex
+	actionChannel chan DialogActionId
+}
+
+func NewFileDiffDialog(application *tview.Application, file *data.FileBrowserEntry, snapshot *data.SnapshotBrowserEntry) *FileDiffDialog {
+	dialog := &FileDiffDialog{
+		application:   application,
+		file:          file,
+		snapshot:      snapshot,
+		actionChannel: make(chan DialogActionId),
+	}
+
+	dialog.createLayout()
+
+	return dialog
+}
+
+func (d *FileDiffDialog) createLayout() {
+	dialogTitle := " File Diff "
+
+	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]`
+		}
+	}
+	diffText = strings.Join(diffTextLines, "\n")
+
+	textDescriptionView := tview.NewTextView().
+		SetDynamicColors(true).
+		SetRegions(true).
+		SetChangedFunc(func() {
+			d.application.Draw()
+		})
+
+	textDescriptionView.SetText(diffText)
+
+	closeTextView := util.CreateAttentionTextView("Press 'esc' to close")
+
+	dialogContent := tview.NewFlex().SetDirection(tview.FlexRow)
+	dialogContent.AddItem(textDescriptionView, 0, 1, true)
+	dialogContent.AddItem(closeTextView, 1, 0, false)
+	dialogContent.SetBorderPadding(0, 0, 1, 1)
+
+	width := 80
+	height := 20
+	dialog := createModal(dialogTitle, dialogContent, width, height)
+	dialog.SetInputCapture(func(event *tcell.EventKey) *tcell.EventKey {
+		if event.Key() == tcell.KeyEscape {
+			d.Close()
+			return nil
+		}
+		return event
+	})
+	d.layout = dialog
+}
+
+func (d *FileDiffDialog) GetName() string {
+	return string(FileDiffDialogPage)
+}
+
+func (d *FileDiffDialog) GetLayout() *tview.Flex {
+	return d.layout
+}
+
+func (d *FileDiffDialog) GetActionChannel() <-chan DialogActionId {
+	return d.actionChannel
+}
+
+func (d *FileDiffDialog) Close() {
+	go func() {
+		d.actionChannel <- DialogCloseActionId
+	}()
+}

internal/ui/dialog/snapshot_action_dialog.go

@@ -38,8 +38,8 @@ func NewSnapshotActionDialog(application *tview.Application, snapshot *data.Snap
 func (d *SnapshotActionDialog) createLayout() {
 	dialogTitle := " Select Action "
 
-	textDesctiption := fmt.Sprintf("What do you want to do with '%s'?", d.snapshot.Snapshot.Name)
-	textDesctiptionView := tview.NewTextView().SetText(textDesctiption)
+	textDescription := fmt.Sprintf("What do you want to do with '%s'?", d.snapshot.Snapshot.Name)
+	textDescriptionView := tview.NewTextView().SetText(textDescription)
 
 	optionTable := tview.NewTable()
 	optionTable.SetSelectable(true, false)
@@ -100,7 +100,7 @@ func (d *SnapshotActionDialog) createLayout() {
 	}
 
 	dialogContent := tview.NewFlex().SetDirection(tview.FlexRow)
-	dialogContent.AddItem(textDesctiptionView, 0, 1, false)
+	dialogContent.AddItem(textDescriptionView, 0, 1, false)
 	dialogContent.AddItem(optionTable, 0, 1, true)
 
 	dialog := createModal(dialogTitle, dialogContent, 50, 10)

internal/ui/file_browser/file_browser.go

@@ -519,6 +519,9 @@ func (fileBrowser *FileBrowserComponent) openActionDialog(selection *data.FileBr
 	actionDialogLayout := dialog.NewFileActionDialog(fileBrowser.application, selection)
 	actionHandler := func(action dialog.DialogActionId) bool {
 		switch action {
+		case dialog.FileDialogShowDiffActionId:
+			fileBrowser.showDiff(selection, fileBrowser.currentSnapshot)
+			return true
 		case dialog.FileDialogCreateSnapshotDialogActionId:
 			fileBrowser.createSnapshot(selection)
 			return true
@@ -688,6 +691,7 @@ func (fileBrowser *FileBrowserComponent) showDialog(d dialog.Dialog, actionHandl
 			}
 			if action == dialog.DialogCloseActionId {
 				fileBrowser.layout.RemovePage(d.GetName())
+				fileBrowser.application.Draw()
 			}
 		}
 	}()
@@ -716,6 +720,20 @@ func (fileBrowser *FileBrowserComponent) runRestoreFileAction(entry *data.FileBr
 	})
 }
 
+func (fileBrowser *FileBrowserComponent) showDiff(selection *data.FileBrowserEntry, snapshot *data.SnapshotBrowserEntry) {
+	if selection == nil || snapshot == nil {
+		return
+	}
+	d := dialog.NewFileDiffDialog(fileBrowser.application, selection, snapshot)
+	fileBrowser.showDialog(d, func(action dialog.DialogActionId) bool {
+		switch action {
+		case dialog.DialogCloseActionId:
+			fileBrowser.Refresh()
+		}
+		return false
+	})
+}
+
 func (fileBrowser *FileBrowserComponent) delete(entry *data.FileBrowserEntry) {
 	go func() {
 		path := entry.RealFile.Path

internal/ui/snapshot_browser/snapshot_browser.go

@@ -197,7 +197,8 @@ func (snapshotBrowser *SnapshotBrowserComponent) Refresh(force bool) {
 func (snapshotBrowser *SnapshotBrowserComponent) SetFileEntry(fileEntry *data.FileBrowserEntry) {
 	if fileEntry != nil &&
 		snapshotBrowser.currentFileEntry != nil &&
-		snapshotBrowser.currentFileEntry.GetRealPath() == fileEntry.GetRealPath() {
+		snapshotBrowser.currentFileEntry.GetRealPath() == fileEntry.GetRealPath() &&
+		snapshotBrowser.currentFileEntry.DiffState == fileEntry.DiffState {
 		return
 	}
 	snapshotBrowser.currentFileEntry = fileEntry