orvyn.go

// Package orvyn is a layer on top of BubbleTea to help building complex tui applications.
package orvyn

import (
	"log"

	"github.com/charmbracelet/bubbles/key"
	tea "github.com/charmbracelet/bubbletea"
	"github.com/halsten-dev/orvyn/theme"
)

var (
	// ProcessExit determines if orvyn should manage the global exit keybind.
	ProcessExit bool

	// ExitKeybind to manage global exit
	ExitKeybind key.Binding

	// WindowSize hold the size of the Window.
	WindowSize Size

	// screens is the map holding all Screen that are registered in orvyn.
	screens map[ScreenID]Screen

	// currentScreenID holds the active ScreenID.
	currentScreenID ScreenID

	// previousScreenID holds the previously active ScreenID.
	previousScreenID ScreenID

	activeDialog *dialog

	activeTheme theme.Theme
)

// Init function is used to initialize orvyn and make it useable.
func Init() {
	ExitKeybind = key.NewBinding(key.WithKeys("ctrl+c"))
	ProcessExit = true
	WindowSize = NewSize(100, 100)
	screens = make(map[ScreenID]Screen)
	activeTheme = theme.NewDefaultDarkTheme()
}

func Update(msg tea.Msg) tea.Cmd {
	switch msg := msg.(type) {
	case tea.KeyMsg:
		switch {
		case key.Matches(msg, ExitKeybind):
			if ProcessExit {
				return tea.Quit
			}
		}

	case tea.WindowSizeMsg:
		WindowSize.Width = msg.Width
		WindowSize.Height = msg.Height
	}

	if currentScreenID == "" {
		return nil
	}

	if activeDialog != nil {
		return activeDialog.screen.Update(msg)
	} else {
		return screens[currentScreenID].Update(msg)
	}

}

func Render() string {
	var layout Layout

	if currentScreenID == "" {
		return "Orvyn : No Current Screen"
	}

	if activeDialog != nil {
		layout = activeDialog.screen.Render()
	} else {
		layout = screens[currentScreenID].Render()
	}

	if layout == nil {
		return ""
	}

	layout.Resize(WindowSize)
	return layout.Render()
}

// Helper

func GetKeyMsg(msg tea.Msg) (tea.KeyMsg, bool) {
	if m, ok := msg.(tea.KeyMsg); ok {
		return m, true
	}

	return tea.KeyMsg{}, false
}

// Theme

func GetTheme() theme.Theme {
	return activeTheme
}

func SetTheme(theme theme.Theme) {
	activeTheme = theme
}

// Screen management

// RegisterScreen allows to register a Screen with the given ScreenID.
func RegisterScreen(id ScreenID, screen Screen) {
	screens[id] = screen
}

// SwitchScreen change the currently active screen and called OnExit and OnEnter.
func SwitchScreen(id ScreenID) tea.Cmd {
	var param any

	_, ok := screens[id]

	if !ok {
		log.Fatalf("Orvyn : Screen with ID %s does not exist", id)
		return nil
	}

	if currentScreenID != "" {
		param = screens[currentScreenID].OnExit()
	}

	previousScreenID = currentScreenID

	currentScreenID = id

	return screens[currentScreenID].OnEnter(param)
}

func SwitchToPreviousScreen() tea.Cmd {
	if previousScreenID == "" {
		return nil
	}

	return SwitchScreen(previousScreenID)
}

func SetPreviousScreen(id ScreenID) {
	previousScreenID = id
}

func GetPreviousScreen() ScreenID {
	return previousScreenID
}

// GetScreen returns the Screen for the given registered ScreenID.
func GetScreen(id ScreenID) Screen {
	_, ok := screens[id]

	if !ok {
		return nil
	}

	return screens[id]
}

// GetCurrentScreenID returns the currently active ScreenID.
func GetCurrentScreenID() ScreenID {
	return currentScreenID
}

// Dialog API

func OpenDialog(dialogID ScreenID, dialogScreen Screen, param any) tea.Cmd {
	activeDialog = new(dialog)

	activeDialog.dialogID = dialogID
	activeDialog.screen = dialogScreen

	return activeDialog.screen.OnEnter(param)
}

func CloseDialog() tea.Cmd {
	param := activeDialog.screen.OnExit()
	id := activeDialog.dialogID

	activeDialog = nil

	return dialogExitCmd(id, param)
}