package main

import (
	"fmt"
	"os"

	tea "charm.land/bubbletea/v2"
)

func main() {
	p := tea.NewProgram(initMainMenu())
	_, err := p.Run()
	if err != nil {
		fmt.Printf("there was an error: %v\n", err)
		os.Exit(1)
	}
}

func initMainMenu() tea.Model {
	return *NewCharmingMap2("menu 0", []CharmingOption2{
		{Option: "menu 1", Result: initMenu1},
		{Option: "menu 2", Result: initMenu2},
	}, "press q to exit", nil)
}

func initMenu1() tea.Model {
	return *NewCharmingMap2("menu 1", nil, "press q to exit, <- to go back", initMainMenu)
}

func initMenu2() tea.Model {
	return *NewCharmingMap2("menu 2", []CharmingOption2{
		{Option: "menu 3", Result: initMenu3},
	}, "press q to exit, <- to go back", initMainMenu)
}

func initMenu3() tea.Model {
	return *NewCharmingMap2("menu 3", nil, "press q to exit, <- to go back", initMenu2)
}

type CharmingOption2 struct {
	Option string
	Result func() tea.Model
}

func NewCharm2(option string, result func() tea.Model) CharmingOption2 {
	return CharmingOption2{option, result}
}

type CharmingMap2 struct {
	title   string
	footer  string
	options []string
	cursor  int
	results []func() tea.Model
	back    func() tea.Model
}

func NewCharmingMap2(title string, options []CharmingOption2, footer string, back func() tea.Model) *CharmingMap2 {
	optionTexts := []string{}
	results := []func() tea.Model{}

	for _, option := range options {
		optionTexts = append(optionTexts, option.Option)
		results = append(results, option.Result)
	}

	return &CharmingMap2{
		title:   title,
		footer:  footer,
		options: optionTexts,
		cursor:  0,
		results: results,
		back:    back,
	}
}

// ----- TUI functions -----

func (m CharmingMap2) Init() tea.Cmd {
	return nil
}

func (m CharmingMap2) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
	switch msg := msg.(type) {
	case tea.KeyPressMsg:
		switch msg.String() {
		case "ctrl+c", "q":
			return m, tea.Quit
		case "up", "k":
			if len(m.options) > 0 {
				if m.cursor > 0 {
					m.cursor--
				} else {
					m.cursor = len(m.options) - 1
				}
			}
		case "down", "j":
			if len(m.options) > 0 {
				if m.cursor < len(m.options)-1 {
					m.cursor++
				} else {
					m.cursor = 0
				}
			}
		case "enter", "space", "right":
			if m.cursor < len(m.results) {
				if m.results[m.cursor] != nil {
					return m.results[m.cursor](), nil
				} else {
					// doesn't get deleted
					return m, tea.Println("no result defined, i'm in " + m.title)
				}
			} else {
				// gets deleted by new view render
				return m, tea.Println("no childs found, i'm in " + m.title)
			}
		case "backspace", "left":
			if m.back != nil {
				return m.back(), nil
			}
		}
	}
	return m, nil
}

func (m CharmingMap2) View() tea.View {
	s := m.title
	s += "\n\n"

	// draw options
	for i, option := range m.options {
		cursor := " "
		if m.cursor == i {
			cursor = ">"
		}

		s += fmt.Sprintf("  %s %s\n", cursor, option)
	}

	// the footer
	s += "\n" + m.footer + "\n"

	return tea.NewView(s)
}