package model

import (
	"fmt"

	"github.com/StevanFreeborn/term-tier/internal/handlers"
	"github.com/StevanFreeborn/term-tier/internal/state"
	"github.com/StevanFreeborn/term-tier/internal/styles"
	"github.com/charmbracelet/bubbles/textinput"
	tea "github.com/charmbracelet/bubbletea"
	"github.com/charmbracelet/lipgloss"
)

type Mode int

const (
	ModeNav Mode = iota
	ModeInput
)

type Model struct {
	State              state.State
	KeyMsgHandlers     []handlers.KeyMsgHandler
	WinSizeMsgHandlers []handlers.WinSizeMsgHandler
}

type option func(m *Model)

func New(state state.State, opts ...option) Model {
	ti := textinput.New()
	ti.CharLimit = 50
	ti.Width = 30

	m := Model{
		State: state,
	}

	for _, opt := range opts {
		opt(&m)
	}

	return m
}

func WithKeyMsgHandlers(handlers []handlers.KeyMsgHandler) option {
	return func(m *Model) {
		m.KeyMsgHandlers = handlers
	}
}

func WithWinSizeMsgHandlers(handlers []handlers.WinSizeMsgHandler) option {
	return func(m *Model) {
		m.WinSizeMsgHandlers = handlers
	}
}

func (m Model) Init() tea.Cmd {
	return textinput.Blink
}

func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
	switch msg := msg.(type) {
	case tea.WindowSizeMsg:
		for _, handler := range m.WinSizeMsgHandlers {
			if handler.Match(m.State, msg) {
				return m, handler.Handle(m.State, msg)
			}
		}
	case tea.KeyMsg:
		for _, handler := range m.KeyMsgHandlers {
			if handler.Match(m.State, msg) {
				return m, handler.Handle(m.State, msg)
			}
		}
	}

	return m, nil
}

func (m Model) View() string {
	if m.State.Mode() == state.InputMode {
		return fmt.Sprintf(
			"\n  %s\n\n%s\n\n  (Enter to Confirm, Esc to Cancel)",
			m.State.InputTitle(),
			styles.InputBoxStyle.Render(m.State.Input().View()),
		)
	}

	if m.State.Mode() == state.HelpMode {
		helpText := "  HELP MENU\n\n"

		for _, handler := range m.KeyMsgHandlers {
			if desc := handler.Description(); desc != "" {
				keys := handler.KeysHandled()
				helpText += fmt.Sprintf("  %s: %s\n", keys, desc)
			}
		}

		helpText += "\n  (Press ? to close this menu)"

		box := styles.HelpBoxStyle.Render(helpText)

		return lipgloss.Place(
			m.State.WindowWidth(),
			m.State.WindowHeight(),
			lipgloss.Center,
			lipgloss.Center,
			box,
		)
	}

	s := "[?] Help  ️  [q] Quit\n\n"

	availableWidth := max(m.State.WindowWidth()-15, 20)

	for tierIndex, tier := range m.State.Tiers() {
		var rows []string
		var currentRowItems []string
		currentWidth := 0

		for itemIndex, item := range tier.Items {
			renderStyle := styles.ItemStyle
			isFocused := tierIndex == m.State.CursorRow() && itemIndex == m.State.CursorCol()

			if isFocused {
				if m.State.Dragging() {
					renderStyle = styles.DraggingItemStyle
				} else {
					renderStyle = styles.SelectedItemStyle
				}
			}

			renderedItem := renderStyle.Render(string(item))
			itemWidth := lipgloss.Width(renderedItem)

			if currentWidth+itemWidth > availableWidth && len(currentRowItems) > 0 {
				rows = append(rows, lipgloss.JoinHorizontal(lipgloss.Top, currentRowItems...))
				currentRowItems = []string{renderedItem}
				currentWidth = itemWidth
			} else {
				currentRowItems = append(currentRowItems, renderedItem)
				currentWidth += itemWidth
			}
		}

		if len(tier.Items) == 0 && tierIndex == m.State.CursorRow() {
			ghost := lipgloss.NewStyle().Foreground(lipgloss.Color("240")).Render(" [ ]")
			currentRowItems = append(currentRowItems, ghost)
		}

		if len(currentRowItems) > 0 {
			rows = append(rows, lipgloss.JoinHorizontal(lipgloss.Top, currentRowItems...))
		}

		itemBlock := lipgloss.JoinVertical(lipgloss.Left, rows...)

		blockHeight := lipgloss.Height(itemBlock)

		label := styles.TierLabelStyle.
			Background(tier.Color).
			Height(blockHeight).
			AlignVertical(lipgloss.Center).
			Render(tier.Name)

		row := lipgloss.JoinHorizontal(lipgloss.Center, label, itemBlock)

		s += row + "\n\n"
	}

	if m.State.StatusMsg() != "" {
		s += styles.StatusStyle.Render("  STATUS: " + m.State.StatusMsg())
	}

	return s
}