package gui

import (
	"github.com/jesseduffield/gocui"
	"github.com/jesseduffield/lazygit/pkg/commands"
	"github.com/jesseduffield/lazygit/pkg/gui/presentation"
)

// list panel functions

func (gui *Gui) getSelectedReflogCommit() *commands.Commit {
	selectedLine := gui.State.Panels.ReflogCommits.SelectedLine
	reflogComits := gui.State.FilteredReflogCommits
	if selectedLine == -1 || len(reflogComits) == 0 {
		return nil
	}

	return reflogComits[selectedLine]
}

func (gui *Gui) handleReflogCommitSelect(g *gocui.Gui, v *gocui.View) error {
	if gui.popupPanelFocused() {
		return nil
	}

	gui.State.SplitMainPanel = false

	if _, err := gui.g.SetCurrentView(v.Name()); err != nil {
		return err
	}

	gui.getMainView().Title = "Reflog Entry"

	commit := gui.getSelectedReflogCommit()
	if commit == nil {
		return gui.newStringTask("main", "No reflog history")
	}
	v.FocusPoint(0, gui.State.Panels.ReflogCommits.SelectedLine)

	if gui.inDiffMode() {
		return gui.renderDiff()
	}

	cmd := gui.OSCommand.ExecutableFromString(
		gui.GitCommand.ShowCmdStr(commit.Sha, gui.State.FilterPath),
	)
	if err := gui.newPtyTask("main", cmd); err != nil {
		gui.Log.Error(err)
	}

	return nil
}

// the reflogs panel is the only panel where we cache data, in that we only
// load entries that have been created since we last ran the call. This means
// we need to be more careful with how we use this, and to ensure we're emptying
// the reflogs array when changing contexts.
// This method also manages two things: ReflogCommits and FilteredReflogCommits.
// FilteredReflogCommits are rendered in the reflogs panel, and ReflogCommits
// are used by the branches panel to obtain recency values for sorting.
func (gui *Gui) refreshReflogCommits() error {
	// pulling state into its own variable incase it gets swapped out for another state
	// and we get an out of bounds exception
	state := gui.State
	var lastReflogCommit *commands.Commit
	if len(state.ReflogCommits) > 0 {
		lastReflogCommit = state.ReflogCommits[0]
	}

	refresh := func(stateCommits *[]*commands.Commit, filterPath string) error {
		commits, onlyObtainedNewReflogCommits, err := gui.GitCommand.GetReflogCommits(lastReflogCommit, filterPath)
		if err != nil {
			return gui.surfaceError(err)
		}

		if onlyObtainedNewReflogCommits {
			*stateCommits = append(commits, *stateCommits...)
		} else {
			*stateCommits = commits
		}
		return nil
	}

	if err := refresh(&state.ReflogCommits, ""); err != nil {
		return err
	}

	if gui.inFilterMode() {
		if err := refresh(&state.FilteredReflogCommits, state.FilterPath); err != nil {
			return err
		}
	} else {
		state.FilteredReflogCommits = state.ReflogCommits
	}

	if gui.getCommitsView().Context == "reflog-commits" {
		return gui.renderReflogCommitsWithSelection()
	}

	return nil
}

func (gui *Gui) renderReflogCommitsWithSelection() error {
	commitsView := gui.getCommitsView()

	gui.refreshSelectedLine(&gui.State.Panels.ReflogCommits.SelectedLine, len(gui.State.FilteredReflogCommits))
	displayStrings := presentation.GetReflogCommitListDisplayStrings(gui.State.FilteredReflogCommits, gui.State.ScreenMode != SCREEN_NORMAL, gui.State.Diff.Ref)
	gui.renderDisplayStrings(commitsView, displayStrings)
	if gui.g.CurrentView() == commitsView && commitsView.Context == "reflog-commits" {
		if err := gui.handleReflogCommitSelect(gui.g, commitsView); err != nil {
			return err
		}
	}

	return nil
}

func (gui *Gui) handleCheckoutReflogCommit(g *gocui.Gui, v *gocui.View) error {
	commit := gui.getSelectedReflogCommit()
	if commit == nil {
		return nil
	}

	err := gui.createConfirmationPanel(g, gui.getCommitsView(), true, gui.Tr.SLocalize("checkoutCommit"), gui.Tr.SLocalize("SureCheckoutThisCommit"), func(g *gocui.Gui, v *gocui.View) error {
		return gui.handleCheckoutRef(commit.Sha, handleCheckoutRefOptions{})
	}, nil)
	if err != nil {
		return err
	}

	gui.State.Panels.ReflogCommits.SelectedLine = 0

	return nil
}

func (gui *Gui) handleCreateReflogResetMenu(g *gocui.Gui, v *gocui.View) error {
	commit := gui.getSelectedReflogCommit()

	return gui.createResetMenu(commit.Sha)
}