#define // This is the master file for minified source, containing various tricks to shrink it as far as possible.
#define // After being fed through gpp, all leading whitespace on every line is removed, and then all line breaks are removed.
#define // End result, an ECMAScript module of fully minified code.

#define Opcode.CreateElement 0
#define Opcode.CreateSvgElement 1
#define Opcode.CreateTextNode 2
#define Opcode.CreateComment 3
#define Opcode.CreateDocumentFragment 4
#define Opcode.SetData 5
#define Opcode.SetAttribute 6
#define Opcode.RemoveAttribute 7
#define Opcode.AppendChild 8
#define Opcode.InsertBefore 9
#define Opcode.Free 10

#define // Global variables (the textDecoder/var1 collision is fine)
#define textDecoder t
#define readString a
#define // Local variables of execute(), readString() and maybe a little else
#define instructions e
#define nodes s
#define offset b
#define var1 t
#define var2 r
#define var3 c
#define length n
#define // Local variables of push_node (also uses nodes)
#define node t
#define id a
#define // VM instance properties
#define NODES t
#define NEXT_ID a
#define push_node e

export default class VM{
	constructor(){
#		define // FIXME: is 0 document or what? (Perhaps I should define a “document” opcode rather than prefilling it?)
#		ifdef WITH_REALLOCATOR
			this.NEXT_ID = 0;
#		endif
		this.NODES=[];
	}

#ifdef WITH_REALLOCATOR
	push_node(node) {
		var nodes=this.NODES,
			id=this.NEXT_ID;
		id<nodes.length||nodes.push(id+1),
		this.NEXT_ID=nodes[id],
		nodes[id]=node
	}
#	define PUSH_NODE this.push_node
#else
#	define PUSH_NODE nodes.push
#endif

	execute(instructions){
		for(
			var var1,
				var2,
				var3,
				nodes=this.NODES,
				length=instructions.byteLength,
				offset=0;
			offset<length;
		)
		while(offset<length)
			switch(
				var3=instructions[offset++],
				var1=instructions[offset++]<<24|instructions[offset++]<<16|instructions[offset++]<<8|instructions[offset++],
				var3
			){
				case Opcode.CreateElement:
#ifdef WITH_SVG
				case Opcode.CreateSvgElement:
#endif
					[var2,offset]=readString(instructions,offset),
					PUSH_NODE(
#ifdef WITH_SVG
						var3?
#define // The way I’m abusing #define for comments here gets veeeeery close to falling apart on the next line! 😀
							nodes[var1].createElementNS("http://www.w3.org/2000/svg",var2):
#endif
							nodes[var1].createElement(var2)
					);
					break;
				case Opcode.CreateTextNode:
					[var2,offset]=readString(instructions,offset),
					PUSH_NODE(nodes[var1].createTextNode(var2));
					break;
#ifdef WITH_COMMENT
				case Opcode.CreateComment:
					[var2,offset]=readString(instructions,offset),
					PUSH_NODE(nodes[var1].createComment(var2));
					break;
#endif
#ifdef WITH_DOCUMENT_FRAGMENT
				case Opcode.CreateDocumentFragment:
					PUSH_NODE(nodes[var1].createDocumentFragment());
					break;
#endif
				case Opcode.SetData:
					[var2,offset]=readString(instructions,offset),
					nodes[var1].data=var2;
					break;
				case Opcode.SetAttribute:
					[var2,offset]=readString(instructions,offset),
					[var3,offset]=readString(instructions,offset),
					nodes[var1].setAttribute(var2,var3);
					break;
				case Opcode.RemoveAttribute:
					[var2,offset]=readString(instructions,offset),
					nodes[var1].removeAttribute(var2);
					break;
				case Opcode.AppendChild:
					nodes[var1].appendChild(nodes[instructions[offset++]<<24|instructions[offset++]<<16|instructions[offset++]<<8|instructions[offset++]]);
					break;
				case Opcode.InsertBefore:
					var2=nodes[instructions[offset++]<<24|instructions[offset++]<<16|instructions[offset++]<<8|instructions[offset++]],
					nodes[var1].insertBefore(
						nodes[instructions[offset++]<<24|instructions[offset++]<<16|instructions[offset++]<<8|instructions[offset++]],
						var2
					);
					break;
				case Opcode.Free:
					delete nodes[var1];
					break
			}
	}
}

var textDecoder=new TextDecoder,
function readString(instructions,offset){
	var length=instructions[offset++]<<24|instructions[offset++]<<16|instructions[offset++]<<8|instructions[offset++];
	return[
		textDecoder.decode(new Uint8Array(instructions.buffer,instructions.byteOffset+offset,length)),
		offset+length
	]
}