gocui/eventMouseDrag.go

// Copyright 2017-2025 WIT.COM Inc. All rights reserved.
// Use of this source code is governed by the GPL 3.0

// 2025 note by jcarr:
// this is one of the coolest things ever worked with.
// Personally, I've been working on making a gocui GO plugin
// so I can use it as a generalized console GUI toolkit.
//
// Well done everyone that has contributed to this gocui project !!!
// I am in your debt. Happy hacking & peace.

package main

import (
	"fmt"
	"time"

	"github.com/awesome-gocui/gocui"
	log "go.wit.com/log"
	"go.wit.com/widget"
)

// this function uses the mouse position to highlight & unhighlight things
// this is run every time the user moves the mouse over the terminal window
func mouseMove(g *gocui.Gui) {
	me.ok = true // this tells init() it's okay to work with gocui
	// very useful for debugging in the past. also, just fun
	if me.supermouse {
		w, h := g.MousePosition()
		for _, tk := range findByXY(w, h) {
			s := fmt.Sprintf("SM (%3d,%3d)", w, h)
			tk.dumpWidget(s)
		}
	}

	if time.Since(me.mouse.down) < me.mouse.clicktime {
		// log.Info("not yet")
		return
	}

	if me.dropdown.active || me.textbox.active {
		// can't drag or do anything when dropdown or textbox are visible
		return
	}
	// okay, the mouse is down and it has been long enough
	// the user is trying to drag something. let's figure out what

	w, h := g.MousePosition()
	// toggle off all highlight vies except for whatever is under the mouse
	for _, view := range g.Views() {
		view.Highlight = false
	}

	if v, err := g.ViewByPosition(w, h); err == nil {
		v.Highlight = true
	}

	// create the 'msg' view if it does not yet exist // TODO: put this somewhere more correct
	if widgetView, _ := g.View("msg"); widgetView == nil {
		if createStdout(g) {
			return
		}
		return
	}

	/*
		if me.mouse.globalMouseDown && (me.dropdown.active || me.textbox.active) {
			log.Info("can't drag while dropdown or textbox are active", w, h)
			return
		}
	*/
	if me.mouse.mouseUp {
		return
	}

	//	if me.mouse.globalMouseDown {
	// log.Info("msgMouseDown == true")
	// plugin will segfault if you don't keep this inside a check for msgMouseDown
	// don't move this code out of here
	var found bool = false
	if me.mouse.currentDrag != nil {
		// me.mouse.currentDrag.dumpWidget(fmt.Sprintf("MM (%3d,%3d)", w, h))
		me.mouse.currentDrag.moveNew()
		return
	}
	// new function that is smarter
	if tk := findWindowUnderMouse(); tk != nil {
		tk.setAsDragging()
		return
	}
	// first look for windows
	for _, tk := range findByXY(w, h) {
		if tk.node.WidgetType == widget.Window {
			tk.setAsDragging()
			return
		}
	}

	// now look for the STDOUT window
	for _, tk := range findByXY(w, h) {
		if tk.node.WidgetType == widget.Flag {
			tk.setAsDragging()
			return
		}
	}
	for _, tk := range findByXY(w, h) {
		if tk.node.WidgetType == widget.Stdout {
			tk.setAsDragging()
			// tk.moveNew()
			return
		}
		/*
			if tk.node.WidgetType == widget.Label {
				me.mouse.currentDrag = tk
				// tk.moveNew()
				return
			}
		*/
		found = true
	}
	if !found {
		log.Info(fmt.Sprintf("findByXY() empty. nothing to move at (%d,%d)", w, h))
	}
}

func (tk *guiWidget) setAsDragging() {
	me.mouse.currentDrag = tk
	tk.lastW = tk.gocuiSize.w0
	tk.lastH = tk.gocuiSize.h0
}

// this is how the window gets dragged around
func (tk *guiWidget) moveNew() {
	w, h := me.baseGui.MousePosition()
	if tk.node.WidgetType == widget.Window {
		tk.window.wasDragged = true

		// compute the new location based off how far the mouse has moved
		// since the mouse button was pressed down
		newW := tk.lastW + w - me.mouse.downW
		newH := tk.lastH + h - me.mouse.downH
		tk.redrawWindow(newW, newH)

		setThingsOnTop() // sets help, Stdout, etc on the top after windows have been redrawn
		return
	}
	if tk.node.WidgetType == widget.Flag {
		me.baseGui.SetView(tk.cuiName, w-3, h-3, w+20, h+20, 0)
		// tk.verifyRect()
		s := fmt.Sprintf("move(%dx%d) %s ###", w, h, tk.cuiName)
		tk.dumpWidget(s)
		return
	}
	if tk.node.WidgetType == widget.Stdout {
		if me.mouse.resize {
			newW := w - me.stdout.lastW
			newH := h - me.stdout.lastH
			me.stdout.w = newW
			me.stdout.h = newH
			log.Info("Resize true", w, h, newW, newH)
			// me.stdout.lastW = w - me.stdout.mouseOffsetW
			// me.stdout.lastH = h - me.stdout.mouseOffsetH
			tk.relocateStdout(me.stdout.lastW, me.stdout.lastH)
		} else {
			// compute the new location based off how far the mouse has moved
			// since the mouse button was pressed down
			newW := tk.lastW + w - me.mouse.downW
			newH := tk.lastH + h - me.mouse.downH
			tk.relocateStdout(newW, newH)
		}
	}
	// always place the help menu on top
	setThingsOnTop() // sets help, Stdout, etc on the top after windows have been redrawn
}