package tui

import (
	// "git.iamthefij.com/iamthefij/slog"
	tea "github.com/charmbracelet/bubbletea"
	"github.com/charmbracelet/lipgloss"
)

type MultiViewModel struct {
	// Internal state
	columns           []tea.Model
	activeIndex       int
	mainModel         tea.Model
	lastWindowSizeMsg tea.WindowSizeMsg

	// Styles for system
	BaseStyle          lipgloss.Style
	ActiveStyle        lipgloss.Style
	NumVisibleSections int
	SideColumnWidth    int

	// Select functionality
	SelectKeys     []string
	OnColumnSelect func(baseModel *MultiViewModel, msg tea.Msg) tea.Cmd
	BackKeys       []string
	OnColumnBack   func(baseModel *MultiViewModel, msg tea.Msg) tea.Cmd
	QuitKeys       []string
}

func NewMultiViewModel(columns []tea.Model, main tea.Model) *MultiViewModel {
	baseStyle := lipgloss.NewStyle().Margin(1)

	return &MultiViewModel{
		columns:     columns,
		activeIndex: 0,
		mainModel:   main,

		BaseStyle: baseStyle,
		ActiveStyle: baseStyle.Copy().UnsetMargins().BorderStyle(lipgloss.NormalBorder()).BorderForeground(
			lipgloss.Color("21"),
		),
		NumVisibleSections: 2,
		SideColumnWidth:    40,

		SelectKeys: []string{tea.KeyEnter.String(), tea.KeyTab.String()},
		OnColumnSelect: func(baseModel *MultiViewModel, msg tea.Msg) tea.Cmd {
			baseModel.NextView()

			return nil
		},
		BackKeys: []string{tea.KeyEsc.String(), tea.KeyShiftTab.String()},
		OnColumnBack: func(baseModel *MultiViewModel, msg tea.Msg) tea.Cmd {
			baseModel.PreviousView()

			return nil
		},
		QuitKeys: []string{"q"},
	}
}

func (m MultiViewModel) GetActiveIndex() int {
	return m.activeIndex
}

func (m MultiViewModel) GetActiveView() *tea.Model {
	if m.activeIndex < len(m.columns) {
		return &m.columns[m.activeIndex]
	}

	return &m.mainModel
}

func (m *MultiViewModel) SetActiveView(viewModel tea.Model) {
	if m.activeIndex < len(m.columns) {
		m.columns[m.activeIndex] = viewModel
	} else {
		m.mainModel = viewModel
	}
}

func (m *MultiViewModel) NextView() *tea.Model {
	if m.activeIndex < len(m.columns) {
		m.activeIndex++
	}

	return m.GetActiveView()
}

func (m *MultiViewModel) PreviousView() *tea.Model {
	if m.activeIndex > 0 {
		m.activeIndex--
	}

	return m.GetActiveView()
}

func (m *MultiViewModel) SetMainView(mainView tea.Model) {
	top, right, bottom, left := m.BaseStyle.GetMargin()
	m.mainModel, _ = mainView.Update(tea.WindowSizeMsg{
		Height: m.lastWindowSizeMsg.Height - top - bottom,
		Width:  m.MainSectionWidth() - right - left,
	})
}

func (m *MultiViewModel) ClearMainView() {
	m.mainModel = nil
}

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

func (m MultiViewModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
	var cmd tea.Cmd

	switch msg := msg.(type) {
	case tea.KeyMsg:
		// Pass key strokes to active view
		var updatedView tea.Model
		updatedView, cmd = (*m.GetActiveView()).Update(msg)

		switch {
		case m.activeIndex < 0:
			panic("where are we!?")
		case m.activeIndex < len(m.columns):
			m.columns[m.activeIndex] = updatedView
		case m.activeIndex >= len(m.columns):
			m.mainModel = updatedView
		}

		// Handle global quit
		for _, quitKey := range m.QuitKeys {
			if quitKey == msg.String() {
				return m, tea.Quit
			}
		}

		// Handle select key
		for _, selectKey := range m.SelectKeys {
			if selectKey == msg.String() {
				m.OnColumnSelect(&m, msg)

				break
			}
		}
		// Handle back key
		for _, selectKey := range m.BackKeys {
			if selectKey == msg.String() {
				m.OnColumnBack(&m, msg)

				break
			}
		}

	case tea.WindowSizeMsg:
		// Pass size message to all sub views
		top, right, bottom, left := m.BaseStyle.GetMargin()
		// top, right, bottom, left := m.BaseStyle.GetBorderStyle().GetTopSize
		for i, model := range m.columns {
			m.columns[i], _ = model.Update(tea.WindowSizeMsg{
				Height: msg.Height - top - bottom,
				Width:  m.SideColumnWidth - right - left,
			})
		}

		if m.mainModel != nil {
			m.mainModel, _ = m.mainModel.Update(tea.WindowSizeMsg{
				Height: msg.Height - top - bottom,
				Width:  m.MainSectionWidth() - right - left,
			})
		}

		m.lastWindowSizeMsg = msg
	}

	return m, cmd
}

func (m MultiViewModel) MainSectionWidth() int {
	return m.lastWindowSizeMsg.Width - (m.SideColumnWidth * m.NumVisibleSections)
}

func (m MultiViewModel) View() string {
	allModels := []tea.Model{}
	allModels = append(allModels, m.columns...)

	if m.mainModel != nil {
		allModels = append(allModels, m.mainModel)
	}

	visibleContent := []string{}

	// Add visible columns
	sideColStyle := m.BaseStyle.Copy().Width(m.SideColumnWidth)
	mainStyle := m.BaseStyle.Copy().Width(m.MainSectionWidth())

	for i, column := range allModels {
		// Get the correct style
		style := sideColStyle
		if i >= len(m.columns) {
			style = mainStyle
		}

		isVisible := m.NumVisibleSections < 1 || i < m.activeIndex+m.NumVisibleSections
		if isVisible {
			if i == m.activeIndex {
				visibleContent = append(visibleContent, m.ActiveStyle.Inherit(style).Render(column.View()))
			} else {
				visibleContent = append(visibleContent, style.Render(column.View()))
			}
		}
	}

	return lipgloss.JoinHorizontal(lipgloss.Top, visibleContent...)
}