Introduce filtered list view model

We're going to start supporting filtering of list views

4 files changed, 210 insertions, 4 deletions

diff --git a/pkg/gui/controllers/helpers/confirmation_helper.go b/pkg/gui/controllers/helpers/confirmation_helper.go
index 7968933fc..c721310b2 100644
--- a/pkg/gui/controllers/helpers/confirmation_helper.go
+++ b/pkg/gui/controllers/helpers/confirmation_helper.go
@@ -292,7 +292,9 @@ func (self *ConfirmationHelper) ResizePopupPanel(v *gocui.View, content string)
 }
 
 func (self *ConfirmationHelper) resizeMenu() {
-	itemCount := self.c.Contexts().Menu.GetList().Len()
+	// we want the unfiltered length here so that if we're filtering we don't
+	// resize the window
+	itemCount := self.c.Contexts().Menu.UnfilteredLen()
 	offset := 3
 	panelWidth := self.getPopupPanelWidth()
 	x0, y0, x1, y1 := self.getPopupPanelDimensionsForContentHeight(panelWidth, itemCount+offset)
diff --git a/pkg/gui/controllers/helpers/helpers.go b/pkg/gui/controllers/helpers/helpers.go
index faf342f0a..846638249 100644
--- a/pkg/gui/controllers/helpers/helpers.go
+++ b/pkg/gui/controllers/helpers/helpers.go
@@ -46,6 +46,7 @@ type Helpers struct {
 	Mode              *ModeHelper
 	AppStatus         *AppStatusHelper
 	WindowArrangement *WindowArrangementHelper
+	Search            *SearchHelper
 }
 
 func NewStubHelpers() *Helpers {
@@ -78,5 +79,6 @@ func NewStubHelpers() *Helpers {
 		Mode:              &ModeHelper{},
 		AppStatus:         &AppStatusHelper{},
 		WindowArrangement: &WindowArrangementHelper{},
+		Search:            &SearchHelper{},
 	}
 }
diff --git a/pkg/gui/controllers/helpers/search_helper.go b/pkg/gui/controllers/helpers/search_helper.go
new file mode 100644
index 000000000..9c0e09db4
--- /dev/null
+++ b/pkg/gui/controllers/helpers/search_helper.go
@@ -0,0 +1,196 @@
+package helpers
+
+import (
+	"github.com/jesseduffield/gocui"
+	"github.com/jesseduffield/lazygit/pkg/gui/types"
+)
+
+// NOTE: this helper supports both filtering and searching. Filtering is when
+// the contents of the list are filtered, whereas searching does not actually
+// change the contents of the list but instead just highlights the search.
+// The general term we use to capture both searching and filtering is...
+// 'searching', which is unfortunate but I can't think of a better name.
+
+type SearchHelper struct {
+	c *HelperCommon
+}
+
+func NewSearchHelper(
+	c *HelperCommon,
+) *SearchHelper {
+	return &SearchHelper{
+		c: c,
+	}
+}
+
+func (self *SearchHelper) OpenFilterPrompt(context types.IFilterableContext) error {
+	state := self.searchState()
+
+	state.Context = context
+
+	self.searchPrefixView().SetContent(self.c.Tr.FilterPrefix)
+	promptView := self.promptView()
+	promptView.ClearTextArea()
+	promptView.TextArea.TypeString(context.GetFilter())
+	promptView.RenderTextArea()
+
+	if err := self.c.PushContext(self.c.Contexts().Search); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (self *SearchHelper) OpenSearchPrompt(context types.Context) error {
+	state := self.searchState()
+
+	state.Context = context
+
+	self.searchPrefixView().SetContent(self.c.Tr.SearchPrefix)
+	promptView := self.promptView()
+	// TODO: should we show the currently searched thing here? Perhaps we can store that on the context
+	promptView.ClearTextArea()
+	promptView.RenderTextArea()
+
+	if err := self.c.PushContext(self.c.Contexts().Search); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (self *SearchHelper) DisplayFilterPrompt(context types.IFilterableContext) {
+	state := self.searchState()
+
+	state.Context = context
+	searchString := context.GetFilter()
+
+	self.searchPrefixView().SetContent(self.c.Tr.FilterPrefix)
+	promptView := self.promptView()
+	promptView.ClearTextArea()
+	promptView.TextArea.TypeString(searchString)
+	promptView.RenderTextArea()
+}
+
+func (self *SearchHelper) DisplaySearchPrompt(context types.ISearchableContext) {
+	state := self.searchState()
+
+	state.Context = context
+	searchString := context.GetSearchString()
+
+	self.searchPrefixView().SetContent(self.c.Tr.SearchPrefix)
+	promptView := self.promptView()
+	promptView.ClearTextArea()
+	promptView.TextArea.TypeString(searchString)
+	promptView.RenderTextArea()
+}
+
+func (self *SearchHelper) searchState() *types.SearchState {
+	return self.c.State().GetRepoState().GetSearchState()
+}
+
+func (self *SearchHelper) searchPrefixView() *gocui.View {
+	return self.c.Views().SearchPrefix
+}
+
+func (self *SearchHelper) promptView() *gocui.View {
+	return self.c.Contexts().Search.GetView()
+}
+
+func (self *SearchHelper) promptContent() string {
+	return self.c.Contexts().Search.GetView().TextArea.GetContent()
+}
+
+func (self *SearchHelper) Confirm() error {
+	state := self.searchState()
+	if self.promptContent() == "" {
+		return self.CancelPrompt()
+	}
+
+	switch state.SearchType() {
+	case types.SearchTypeFilter:
+		return self.ConfirmFilter()
+	case types.SearchTypeSearch:
+		return self.ConfirmSearch()
+	case types.SearchTypeNone:
+		return self.c.PopContext()
+	}
+
+	return nil
+}
+
+func (self *SearchHelper) ConfirmFilter() error {
+	// We also do this on each keypress but we do it here again just in case
+	state := self.searchState()
+
+	context, ok := state.Context.(types.IFilterableContext)
+	if !ok {
+		self.c.Log.Warnf("Context %s is not filterable", state.Context.GetKey())
+		return nil
+	}
+
+	context.SetFilter(self.promptContent())
+	_ = self.c.PostRefreshUpdate(state.Context)
+
+	return self.c.PopContext()
+}
+
+func (self *SearchHelper) ConfirmSearch() error {
+	state := self.searchState()
+
+	if err := self.c.PopContext(); err != nil {
+		return err
+	}
+
+	context, ok := state.Context.(types.ISearchableContext)
+	if !ok {
+		self.c.Log.Warnf("Context %s is searchable", state.Context.GetKey())
+		return nil
+	}
+
+	searchString := self.promptContent()
+	context.SetSearchString(searchString)
+
+	view := context.GetView()
+
+	if err := view.Search(searchString); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (self *SearchHelper) CancelPrompt() error {
+	self.Cancel()
+
+	return self.c.PopContext()
+}
+
+func (self *SearchHelper) Cancel() {
+	state := self.searchState()
+
+	switch context := state.Context.(type) {
+	case types.IFilterableContext:
+		context.SetFilter("")
+		_ = self.c.PostRefreshUpdate(context)
+	case types.ISearchableContext:
+		context.GetView().ClearSearch()
+	default:
+		// do nothing
+	}
+
+	state.Context = nil
+}
+
+func (self *SearchHelper) OnPromptContentChanged(searchString string) {
+	state := self.searchState()
+	switch context := state.Context.(type) {
+	case types.IFilterableContext:
+		context.SetFilter(searchString)
+		_ = self.c.PostRefreshUpdate(context)
+	case types.ISearchableContext:
+		// do nothing
+	default:
+		// do nothing (shouldn't land here)
+	}
+}
diff --git a/pkg/gui/controllers/helpers/window_arrangement_helper.go b/pkg/gui/controllers/helpers/window_arrangement_helper.go
index 20459993f..b45586764 100644
--- a/pkg/gui/controllers/helpers/window_arrangement_helper.go
+++ b/pkg/gui/controllers/helpers/window_arrangement_helper.go
@@ -55,7 +55,7 @@ func (self *WindowArrangementHelper) GetWindowDimensions(informationStr string,
 	self.c.Modes().Filtering.Active()
 
 	showInfoSection := self.c.UserConfig.Gui.ShowBottomLine ||
-		self.c.State().GetRepoState().IsSearching() ||
+		self.c.State().GetRepoState().InSearchPrompt() ||
 		self.modeHelper.IsAnyModeActive() ||
 		self.appStatusHelper.HasStatus()
 	infoSectionSize := 0
@@ -174,11 +174,17 @@ func (self *WindowArrangementHelper) getMidSectionWeights() (int, int) {
 }
 
 func (self *WindowArrangementHelper) infoSectionChildren(informationStr string, appStatus string) []*boxlayout.Box {
-	if self.c.State().GetRepoState().IsSearching() {
+	if self.c.State().GetRepoState().InSearchPrompt() {
+		var prefix string
+		if self.c.State().GetRepoState().GetSearchState().SearchType() == types.SearchTypeSearch {
+			prefix = self.c.Tr.SearchPrefix
+		} else {
+			prefix = self.c.Tr.FilterPrefix
+		}
 		return []*boxlayout.Box{
 			{
 				Window: "searchPrefix",
-				Size:   runewidth.StringWidth(self.c.Tr.SearchPrefix),
+				Size:   runewidth.StringWidth(prefix),
 			},
 			{
 				Window: "search",