lazygit/pkg/gui/layout.go

package gui

import (
	"fmt"

	"github.com/fatih/color"
	"github.com/jesseduffield/gocui"
	"github.com/jesseduffield/lazygit/pkg/theme"
	"github.com/jesseduffield/lazygit/pkg/utils"
)

const SEARCH_PREFIX = "search: "
const INFO_SECTION_PADDING = " "

// getFocusLayout returns a manager function for when view gain and lose focus
func (gui *Gui) getFocusLayout() func(g *gocui.Gui) error {
	var previousView *gocui.View
	return func(g *gocui.Gui) error {
		newView := gui.g.CurrentView()
		if err := gui.onFocusChange(); err != nil {
			return err
		}
		// for now we don't consider losing focus to a popup panel as actually losing focus
		if newView != previousView && !gui.isPopupPanel(newView.Name()) {
			if err := gui.onFocusLost(previousView, newView); err != nil {
				return err
			}
			if err := gui.onFocus(newView); err != nil {
				return err
			}
			previousView = newView
		}
		return nil
	}
}

func (gui *Gui) onFocusChange() error {
	currentView := gui.g.CurrentView()
	for _, view := range gui.g.Views() {
		view.Highlight = view == currentView
	}
	return nil
}

func (gui *Gui) onFocusLost(v *gocui.View, newView *gocui.View) error {
	if v == nil {
		return nil
	}
	if v.IsSearching() && newView.Name() != "search" {
		if err := gui.onSearchEscape(); err != nil {
			return err
		}
	}
	switch v.Name() {
	case "main":
		// if we have lost focus to a first-class panel, we need to do some cleanup
		gui.changeMainViewsContext("normal")
	case "commitFiles":
		if gui.State.MainContext != "patch-building" {
			if _, err := gui.g.SetViewOnBottom(v.Name()); err != nil {
				return err
			}
		}
	}
	gui.Log.Info(v.Name() + " focus lost")
	return nil
}

func (gui *Gui) onFocus(v *gocui.View) error {
	if v == nil {
		return nil
	}
	gui.Log.Info(v.Name() + " focus gained")
	return nil
}

func (gui *Gui) informationStr() string {
	if gui.inDiffMode() {
		return utils.ColoredString(fmt.Sprintf("%s %s %s", gui.Tr.SLocalize("showingGitDiff"), "git diff "+gui.diffStr(), utils.ColoredString(gui.Tr.SLocalize("(reset)"), color.Underline)), color.FgMagenta)
	} else if gui.inFilterMode() {
		return utils.ColoredString(fmt.Sprintf("%s '%s' %s", gui.Tr.SLocalize("filteringBy"), gui.State.FilterPath, utils.ColoredString(gui.Tr.SLocalize("(reset)"), color.Underline)), color.FgRed, color.Bold)
	} else if len(gui.State.CherryPickedCommits) > 0 {
		return utils.ColoredString(fmt.Sprintf("%d commits copied", len(gui.State.CherryPickedCommits)), color.FgCyan)
	} else if gui.g.Mouse {
		donate := color.New(color.FgMagenta, color.Underline).Sprint(gui.Tr.SLocalize("Donate"))
		return donate + " " + gui.Config.GetVersion()
	} else {
		return gui.Config.GetVersion()
	}
}

// layout is called for every screen re-render e.g. when the screen is resized
func (gui *Gui) layout(g *gocui.Gui) error {
	g.Highlight = true
	width, height := g.Size()

	minimumHeight := 9
	minimumWidth := 10
	if height < minimumHeight || width < minimumWidth {
		v, err := g.SetView("limit", 0, 0, width-1, height-1, 0)
		if err != nil {
			if err.Error() != "unknown view" {
				return err
			}
			v.Title = gui.Tr.SLocalize("NotEnoughSpace")
			v.Wrap = true
			_, _ = g.SetViewOnTop("limit")
		}
		return nil
	}

	informationStr := gui.informationStr()
	appStatus := gui.statusManager.getStatusString()

	viewDimensions := gui.getViewDimensions(informationStr, appStatus)

	_, _ = g.SetViewOnBottom("limit")
	_ = g.DeleteView("limit")

	textColor := theme.GocuiDefaultTextColor

	// reading more lines into main view buffers upon resize
	prevMainView, err := gui.g.View("main")
	if err == nil {
		_, prevMainHeight := prevMainView.Size()
		newMainHeight := viewDimensions["main"].Y1 - viewDimensions["main"].Y0 - 1
		heightDiff := newMainHeight - prevMainHeight
		if heightDiff > 0 {
			if manager, ok := gui.viewBufferManagerMap["main"]; ok {
				manager.ReadLines(heightDiff)
			}
			if manager, ok := gui.viewBufferManagerMap["secondary"]; ok {
				manager.ReadLines(heightDiff)
			}
		}
	}

	setViewFromDimensions := func(viewName string, boxName string, frame bool) (*gocui.View, error) {
		dimensionsObj := viewDimensions[boxName]
		frameOffset := 1
		if frame {
			frameOffset = 0
		}
		return g.SetView(
			viewName,
			dimensionsObj.X0-frameOffset,
			dimensionsObj.Y0-frameOffset,
			dimensionsObj.X1+frameOffset,
			dimensionsObj.Y1+frameOffset,
			0,
		)
	}

	v, err := setViewFromDimensions("main", "main", true)
	if err != nil {
		if err.Error() != "unknown view" {
			return err
		}
		v.Title = gui.Tr.SLocalize("DiffTitle")
		v.Wrap = true
		v.FgColor = textColor
		v.IgnoreCarriageReturns = true
	}

	secondaryView, err := setViewFromDimensions("secondary", "secondary", true)
	if err != nil {
		if err.Error() != "unknown view" {
			return err
		}
		secondaryView.Title = gui.Tr.SLocalize("DiffTitle")
		secondaryView.Wrap = true
		secondaryView.FgColor = textColor
		secondaryView.IgnoreCarriageReturns = true
	}

	hiddenViewOffset := 9999

	if v, err := setViewFromDimensions("status", "status", true); err != nil {
		if err.Error() != "unknown view" {
			return err
		}
		v.Title = gui.Tr.SLocalize("StatusTitle")
		v.FgColor = textColor
	}

	filesView, err := setViewFromDimensions("files", "files", true)
	if err != nil {
		if err.Error() != "unknown view" {
			return err
		}
		filesView.Highlight = true
		filesView.Title = gui.Tr.SLocalize("FilesTitle")
		filesView.ContainsList = true
	}

	branchesView, err := setViewFromDimensions("branches", "branches", true)
	if err != nil {
		if err.Error() != "unknown view" {
			return err
		}
		branchesView.Title = gui.Tr.SLocalize("BranchesTitle")
		branchesView.Tabs = []string{"Local Branches", "Remotes", "Tags"}
		branchesView.FgColor = textColor
		branchesView.ContainsList = true
	}

	commitFilesView, err := setViewFromDimensions("commitFiles", "commits", true)
	if err != nil {
		if err.Error() != "unknown view" {
			return err
		}
		commitFilesView.Title = gui.Tr.SLocalize("CommitFiles")
		commitFilesView.FgColor = textColor
		commitFilesView.ContainsList = true
	}

	commitsView, err := setViewFromDimensions("commits", "commits", true)
	if err != nil {
		if err.Error() != "unknown view" {
			return err
		}
		commitsView.Title = gui.Tr.SLocalize("CommitsTitle")
		commitsView.Tabs = []string{"Commits", "Reflog"}
		commitsView.FgColor = textColor
		commitsView.ContainsList = true
	}

	stashView, err := setViewFromDimensions("stash", "stash", true)
	if err != nil {
		if err.Error() != "unknown view" {
			return err
		}
		stashView.Title = gui.Tr.SLocalize("StashTitle")
		stashView.FgColor = textColor
		stashView.ContainsList = true
	}

	if gui.getCommitMessageView() == nil {
		// doesn't matter where this view starts because it will be hidden
		if commitMessageView, err := g.SetView("commitMessage", hiddenViewOffset, hiddenViewOffset, hiddenViewOffset+10, hiddenViewOffset+10, 0); err != nil {
			if err.Error() != "unknown view" {
				return err
			}
			_, _ = g.SetViewOnBottom("commitMessage")
			commitMessageView.Title = gui.Tr.SLocalize("CommitMessage")
			commitMessageView.FgColor = textColor
			commitMessageView.Editable = true
			commitMessageView.Editor = gocui.EditorFunc(gui.commitMessageEditor)
		}
	}

	if check, _ := g.View("credentials"); check == nil {
		// doesn't matter where this view starts because it will be hidden
		if credentialsView, err := g.SetView("credentials", hiddenViewOffset, hiddenViewOffset, hiddenViewOffset+10, hiddenViewOffset+10, 0); err != nil {
			if err.Error() != "unknown view" {
				return err
			}
			_, err := g.SetViewOnBottom("credentials")
			if err != nil {
				return err
			}
			credentialsView.Title = gui.Tr.SLocalize("CredentialsUsername")
			credentialsView.FgColor = textColor
			credentialsView.Editable = true
		}
	}

	if v, err := setViewFromDimensions("options", "options", false); err != nil {
		if err.Error() != "unknown view" {
			return err
		}
		v.Frame = false
		v.FgColor = theme.OptionsColor

		// doing this here because it'll only happen once
		if err := gui.onInitialViewsCreation(); err != nil {
			return err
		}
	}

	// this view takes up one character. Its only purpose is to show the slash when searching
	if searchPrefixView, err := setViewFromDimensions("searchPrefix", "searchPrefix", false); err != nil {
		if err.Error() != "unknown view" {
			return err
		}

		searchPrefixView.BgColor = gocui.ColorDefault
		searchPrefixView.FgColor = gocui.ColorGreen
		searchPrefixView.Frame = false
		gui.setViewContent(searchPrefixView, SEARCH_PREFIX)
	}

	if searchView, err := setViewFromDimensions("search", "search", false); err != nil {
		if err.Error() != "unknown view" {
			return err
		}

		searchView.BgColor = gocui.ColorDefault
		searchView.FgColor = gocui.ColorGreen
		searchView.Frame = false
		searchView.Editable = true
	}

	if appStatusView, err := setViewFromDimensions("appStatus", "appStatus", false); err != nil {
		if err.Error() != "unknown view" {
			return err
		}
		appStatusView.BgColor = gocui.ColorDefault
		appStatusView.FgColor = gocui.ColorCyan
		appStatusView.Frame = false
		if _, err := g.SetViewOnBottom("appStatus"); err != nil {
			return err
		}
	}

	informationView, err := setViewFromDimensions("information", "information", false)
	if err != nil {
		if err.Error() != "unknown view" {
			return err
		}
		informationView.BgColor = gocui.ColorDefault
		informationView.FgColor = gocui.ColorGreen
		informationView.Frame = false
		gui.renderString("information", INFO_SECTION_PADDING+informationStr)
	}
	if gui.State.OldInformation != informationStr {
		gui.setViewContent(informationView, informationStr)
		gui.State.OldInformation = informationStr
	}

	if gui.g.CurrentView() == nil {
		initialView := gui.getFilesView()
		if gui.inFilterMode() {
			initialView = gui.getCommitsView()
		}
		if _, err := gui.g.SetCurrentView(initialView.Name()); err != nil {
			return err
		}

		if err := gui.switchFocus(nil, initialView); err != nil {
			return err
		}
	}

	type listViewState struct {
		selectedLine int
		lineCount    int
		view         *gocui.View
		context      string
		listView     *listView
	}

	listViewStates := []listViewState{
		{view: filesView, context: "", selectedLine: gui.State.Panels.Files.SelectedLine, lineCount: len(gui.State.Files), listView: gui.filesListView()},
		{view: branchesView, context: "local-branches", selectedLine: gui.State.Panels.Branches.SelectedLine, lineCount: len(gui.State.Branches), listView: gui.branchesListView()},
		{view: branchesView, context: "remotes", selectedLine: gui.State.Panels.Remotes.SelectedLine, lineCount: len(gui.State.Remotes), listView: gui.remotesListView()},
		{view: branchesView, context: "remote-branches", selectedLine: gui.State.Panels.RemoteBranches.SelectedLine, lineCount: len(gui.State.Remotes), listView: gui.remoteBranchesListView()},
		{view: branchesView, context: "tags", selectedLine: gui.State.Panels.Tags.SelectedLine, lineCount: len(gui.State.Tags), listView: gui.tagsListView()},
		{view: commitsView, context: "branch-commits", selectedLine: gui.State.Panels.Commits.SelectedLine, lineCount: len(gui.State.Commits), listView: gui.branchCommitsListView()},
		{view: commitsView, context: "reflog-commits", selectedLine: gui.State.Panels.ReflogCommits.SelectedLine, lineCount: len(gui.State.FilteredReflogCommits), listView: gui.reflogCommitsListView()},
		{view: stashView, context: "", selectedLine: gui.State.Panels.Stash.SelectedLine, lineCount: len(gui.State.StashEntries), listView: gui.stashListView()},
		{view: commitFilesView, context: "", selectedLine: gui.State.Panels.CommitFiles.SelectedLine, lineCount: len(gui.State.CommitFiles), listView: gui.commitFilesListView()},
	}

	// menu view might not exist so we check to be safe
	if menuView, err := gui.g.View("menu"); err == nil {
		listViewStates = append(listViewStates, listViewState{view: menuView, context: "", selectedLine: gui.State.Panels.Menu.SelectedLine, lineCount: gui.State.MenuItemCount, listView: gui.menuListView()})
	}
	for _, listViewState := range listViewStates {
		// ignore views where the context doesn't match up with the selected line we're trying to focus
		if listViewState.context != "" && (listViewState.view.Context != listViewState.context) {
			continue
		}
		// check if the selected line is now out of view and if so refocus it
		listViewState.view.FocusPoint(0, listViewState.selectedLine)

		listViewState.view.SelBgColor = theme.GocuiSelectedLineBgColor

		// I doubt this is expensive though it's admittedly redundant after the first render
		listViewState.view.SetOnSelectItem(gui.onSelectItemWrapper(listViewState.listView.onSearchSelect))
	}

	mainViewWidth, mainViewHeight := gui.getMainView().Size()
	if mainViewWidth != gui.State.PrevMainWidth || mainViewHeight != gui.State.PrevMainHeight {
		gui.State.PrevMainWidth = mainViewWidth
		gui.State.PrevMainHeight = mainViewHeight
		if err := gui.onResize(); err != nil {
			return err
		}
	}

	// here is a good place log some stuff
	// if you download humanlog and do tail -f development.log | humanlog
	// this will let you see these branches as prettified json
	// gui.Log.Info(utils.AsJson(gui.State.Branches[0:4]))
	return gui.resizeCurrentPopupPanel()
}

func (gui *Gui) onInitialViewsCreation() error {
	gui.changeMainViewsContext("normal")

	gui.getBranchesView().Context = "local-branches"
	gui.getCommitsView().Context = "branch-commits"

	if gui.showRecentRepos {
		if err := gui.handleCreateRecentReposMenu(); err != nil {
			return err
		}
		gui.showRecentRepos = false
	}

	return gui.loadNewRepo()
}

func max(a, b int) int {
	if a > b {
		return a
	}
	return b
}