Start implementing allow-collapse-layout using 3-value layout-func return-valuetest-allowcollapse-via-layout-result-enum

1 files changed, 19 insertions, 10 deletions

diff --git a/src/lib.ts b/src/lib.ts
index ddfc19d..d5941aa 100644
--- a/src/lib.ts
+++ b/src/lib.ts
@@ -39,16 +39,16 @@ export class LayoutTree {
 	}
 	// Attempts layout of TolNode tree, for an area with given xy-coordinate and width+height (in pixels)
 	// 'chg' allows for performing layout after expanding/collapsing a node
-	tryLayout(pos: [number,number], dims: [number,number], chg?: LayoutTreeChg){
+	tryLayout(pos: [number,number], dims: [number,number], allowCollapse: boolean = false, chg: LayoutTreeChg = null){
 		// Create a new LayoutNode tree, keeping the old one in case of layout failure
 		let tempTree = this.root.cloneNodeTree(chg);
-		let success: boolean;
+		let result: LayoutResultEnum;
 		switch (this.options.layoutType){
-			case 'sqr':   success =   sqrLayout(tempTree, pos, dims, true, this.options); break;
-			case 'rect':  success =  rectLayout(tempTree, pos, dims, true, this.options); break;
-			case 'sweep': success = sweepLayout(tempTree, pos, dims, true, this.options); break;
+			case 'sqr':   result =   sqrLayout(tempTree, pos, dims, true, this.options); break;
+			case 'rect':  result =  rectLayout(tempTree, pos, dims, true, this.options); break;
+			case 'sweep': result = sweepLayout(tempTree, pos, dims, true, this.options); break;
 		}
-		if (success){
+		if (result == LayoutResult.Success || result == LayoutResult.SuccessIfCollapse && allowCollapse){
 			tempTree.copyTreeForRender(this.root);
 		}
 		return success;
@@ -176,15 +176,23 @@ type LayoutFn = (
 	showHeader: boolean,
 	opts: LayoutOptions,
 	ownOpts?: any,
-) => boolean;
+) => LayoutResultEnum;
+// Enum used to represent the result of an attempted layout
+const LayoutResult = {
+	Success: 0,
+	Fail: 1,
+	SuccessIfCollapse: 2,
+};
+type LayoutResultEnum = typeof LayoutResult[keyof typeof LayoutResult];
+
 // Lays out node as one square, ignoring child nodes (used for base cases)
 let oneSqrLayout: LayoutFn = function (node, pos, dims, showHeader, opts){
 	let tileSz = Math.min(dims[0], dims[1], opts.maxTileSz);
 	if (tileSz < opts.minTileSz){
-		return false;
+		return LayoutResult.Fail;
 	}
 	node.assignLayoutData(pos, [tileSz,tileSz], {showHeader, empSpc: dims[0]*dims[1] - tileSz**2});
-	return true;
+	return LayoutResult.Success;
 }
 // Lays out nodes as squares within a grid with intervening+surrounding spacing
 let sqrLayout: LayoutFn = function (node, pos, dims, showHeader, opts){
@@ -196,7 +204,7 @@ let sqrLayout: LayoutFn = function (node, pos, dims, showHeader, opts){
 	let newPos = [opts.tileSpacing, opts.tileSpacing + headerSz];
 	let newDims = [dims[0] - opts.tileSpacing, dims[1] - opts.tileSpacing - headerSz];
 	if (newDims[0] * newDims[1] <= 0){
-		return false;
+		return LayoutResult.Fail;
 	}
 	// Find number of rows/columns with least empty space
 	let numChildren = node.children.length;
@@ -226,6 +234,7 @@ let sqrLayout: LayoutFn = function (node, pos, dims, showHeader, opts){
 		}
 	}
 	if (lowestEmpSpc == Number.POSITIVE_INFINITY){
+		
 		return false;
 	}
 	// Layout children