package gui

import (
	"go.wit.com/log"
	"go.wit.com/widget"
)

// Grid numbering examples (H) or (W,H)
// -----------------------
// -- (1) -- (2) -- (3) -- (X)
// -----------------------
//
//    (Y)
// ---------
// -- (1) --
// -- (2) --
// ---------
//
//    (X,Y)
// -----------------------------
// -- (1,1) -- (2,1) -- (3,1) --
// -- (1,2) -- (2,2) -- (3,2) --
// -- (1,3) --       -- (3,3) --
// -----------------------------

type Grid struct {
	Width  int
	Height int
}

type GridOffset struct {
	X int
	Y int
}

func (parent *Node) RawGrid() *Node {
	newNode := parent.newNode("GRID", widget.Grid)

	newNode.W = 0
	newNode.H = 0
	newNode.NextW = 1
	newNode.NextH = 1

	// by default, always pad grids
	newNode.pad = true

	// inform the toolkits
	sendAction(newNode, widget.Add)
	return newNode
}

func (parent *Node) NewGrid(progname string, w int, h int) *Node {
	newNode := parent.newNode(progname, widget.Grid)
	newNode.progname = progname

	newNode.W = w
	newNode.H = h
	newNode.NextW = 1
	newNode.NextH = 1

	// by default, always pad grids
	newNode.pad = true

	// inform the toolkits
	sendAction(newNode, widget.Add)
	return newNode
}

// true if the grid already have a child at W,H
func (n *Node) gridCollision() bool {
	for _, child := range n.children {
		if (child.AtW == n.NextW) && (child.AtH == n.NextH) {
			return true
		}
	}
	return false
}

// keeps incrementing NextW & NextH until there is not a widget
func (n *Node) gridIncrement() {
	if !n.gridCollision() {
		return
	}

	n.NextW += 1
	if n.W == 0 {
		// grid does not have a fixed size
	} else {
		// this grid has bounds, if adding to the grid
		// goes off the edge, then add the widget to the next row
		if n.NextW > n.W {
			n.NextW = 1
			n.NextH += 1
		}
	}

	n.gridIncrement()
}

func (n *Node) At(w int, h int) *Node {
	if n == nil {
		return n
	}

	n.NextW = w
	n.NextH = h

	n.gridIncrement()
	if (n.NextW != w) || (n.NextH != h) {
		log.Log(WARN, "At() (W,H)", w, h, " was moved to avoid a collision (W,H) =", n.NextW, n.NextH)
	}
	return n
}

func (n *Node) NextRow() *Node {
	if n == nil {
		return n
	}

	n.NextW = 1
	n.NextH += 1
	return n
}