Introduce filtered list view model

We're going to start supporting filtering of list views

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)
+	}
+}