package app

import (
	"github.com/charmbracelet/bubbles/list"
	tea "github.com/charmbracelet/bubbletea"
	"github.com/charmbracelet/lipgloss"
)

// Module is the interface that all TUI feature modules must implement.
type Module interface {
	tea.Model
	Title() string
	Description() string
}

// Entry represents a registered module with its factory function.
type Entry struct {
	Title  string
	Desc   string
	Create func() tea.Model
}

// ===== menu item =====

type menuItem struct {
	title string
	desc  string
}

func (mi menuItem) FilterValue() string { return mi.title }
func (mi menuItem) Title() string       { return mi.title }
func (mi menuItem) Description() string { return mi.desc }

// ===== styles =====

var menuStyle = lipgloss.NewStyle().
	Bold(true).
	Foreground(lipgloss.Color("39")).
	PaddingLeft(1)

// ===== model =====

type Model struct {
	menu    list.Model
	active  tea.Model
	entries []Entry
}

func New(entries []Entry) *Model {
	items := make([]list.Item, len(entries))
	for i, e := range entries {
		items[i] = menuItem{title: e.Title, desc: e.Desc}
	}

	l := list.New(items, list.NewDefaultDelegate(), 0, 0)
	l.Title = "ARinera Minecraft 管理工具"
	l.SetShowStatusBar(false)
	l.SetShowHelp(true)

	return &Model{menu: l, entries: entries}
}

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

func (m *Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
	if key, ok := msg.(tea.KeyMsg); ok {
		switch key.String() {
		case "ctrl+c":
			return m, tea.Quit
		case "esc":
			if m.active != nil {
				m.active = nil
				return m, nil
			}
			return m, tea.Quit
		}
	}

	if ws, ok := msg.(tea.WindowSizeMsg); ok {
		if m.active == nil {
			m.menu.SetSize(ws.Width, ws.Height-4)
		}
	}

	if m.active != nil {
		return m.updateModule(msg)
	}
	return m.updateMenu(msg)
}

func (m *Model) updateMenu(msg tea.Msg) (tea.Model, tea.Cmd) {
	switch msg := msg.(type) {
	case tea.KeyMsg:
		if msg.String() == "enter" {
			sel, ok := m.menu.SelectedItem().(menuItem)
			if !ok {
				return m, nil
			}
			for _, e := range m.entries {
				if e.Title == sel.title {
					m.active = e.Create()
					return m, m.active.Init()
				}
			}
		}
	}

	var cmd tea.Cmd
	m.menu, cmd = m.menu.Update(msg)
	return m, cmd
}

func (m *Model) updateModule(msg tea.Msg) (tea.Model, tea.Cmd) {
	newMod, cmd := m.active.Update(msg)
	m.active = newMod
	return m, cmd
}

func (m *Model) View() string {
	if m.active != nil {
		return m.active.View()
	}
	return menuStyle.Render("ARinera Minecraft 管理工具") + "\n\n" + m.menu.View()
}