// LICENSE: same as the go language itself
// Copyright 2023 WIT.COM

// all structures and variables are local (aka lowercase)
// since the plugin should be isolated to access only
// by functions() to insure everything here is run
// inside a dedicated goroutine

package main

import (
	"fmt"
	"sync"
	"github.com/awesome-gocui/gocui"
	"git.wit.org/wit/gui/toolkit"
)

// It's probably a terrible idea to call this 'me'
var me config

type config struct {
	baseGui *gocui.Gui // the main gocui handle
	rootNode *cuiWidget // the base of the binary tree. it should have id == 0
	ctrlDown *cuiWidget // shown if you click the mouse when the ctrl key is pressed

	// this is the channel we send user events like
	// mouse clicks or keyboard events back to the program
	callback chan toolkit.Action

	// this is the channel we get requests to make widgets
	pluginChan chan toolkit.Action

	helpLabel *gocui.View

	defaultBehavior bool
	defaultWidth int
	defaultHeight int
	// nextW int	// where the next window or tab flag should go

	padW int
	padH int

	// where the raw corner is
	rawW int
	rawH int

	bookshelf bool // do you want things arranged in the box like a bookshelf or a stack?
	canvas bool // if set to true, the windows are a raw canvas
	menubar bool // for windows
	stretchy bool // expand things like buttons to the maximum size
	padded bool // add space between things like buttons
	margin bool // add space around the frames of windows

	horizontalPadding int
	groupPadding int
	buttonPadding int
}

var (
	initialMouseX, initialMouseY, xOffset, yOffset int
	globalMouseDown, msgMouseDown, movingMsg bool
)

// the gocui way
// the logical size of the widget
// corner starts at in the upper left corner
type rectType struct {
	// where the widget should calculate it's existance from
	// startW int
	// startH int

	// the actual size
	width int
	height int

	// this is the gocui way
	w0, h0, w1, h1 int      // left top right bottom
}

type cuiWidget struct {
	id int	// widget ID
	// parentId int
	widgetType   toolkit.WidgetType

	name   string // a descriptive name of the widget
	text   string // the current text being displayed
	cuiName string // what gocui uses to reference the widget

	vals []string // dropdown menu options

	// visable bool // track if it's currently supposed to be shown
	isFake bool // widget types like 'box' are 'false'

	// where the widget's real corner is 
	startW int
	startH int

	// where the next child should be placed
	nextW	int
	nextH	int

	// the widget size to reserve or things will overlap
	realWidth int
	realHeight int

	gocuiSize rectType  // the display size of this widget
	// logicalSize rectType  // the logical size. Includes all the child widgets

	// used to track the size of grids
	widths map[int]int // how tall each row in the grid is
	heights map[int]int // how wide each column in the grid is

	// deprecate // where in the parent grid this widget should go
	parentW int
	parentH int

	// things from toolkit/action
	b bool
	i int
	s string
	x int
	y int
	width int
	height int

	// horizontal=true  means layout widgets like books on a bookshelf
	// horizontal=false means layout widgets like books in a stack
	horizontal bool `default:false`

	tainted bool
	v *gocui.View

	// writeMutex protects locks the write process
	writeMutex sync.Mutex

	parent	*cuiWidget
	children []*cuiWidget
}

// from the gocui devs:
// Write appends a byte slice into the view's internal buffer. Because
// View implements the io.Writer interface, it can be passed as parameter
// of functions like fmt.Fprintf, fmt.Fprintln, io.Copy, etc. Clear must
// be called to clear the view's buffer.

func (w *cuiWidget) Write(p []byte) (n int, err error) {
	w.tainted = true
	w.writeMutex.Lock()
	defer w.writeMutex.Unlock()
	if (w.v == nil) {
		return
	}
	w.v.Clear()
	fmt.Fprintln(w.v, p)
	log(logNow, "widget.Write()", p)

	return len(p), nil
}