package hrt.shgraph;

import haxe.macro.Context;
import haxe.macro.Expr;
using haxe.macro.Tools;

class ParseFieldsMacro {

#if macro

	public static function build() : Array<Field> {
		var fields = Context.getBuildFields();

		var mapInputs = new Array<Expr>();
		var inputsList = new Array<String>();
		var hasInputs = false;
		var mapOutputs = new Array<Expr>();
		var outputsList = new Array<String>();
		var hasOutputs = false;

		for ( f in fields ) {
			if( f.meta == null ) continue;
			switch (f.kind) {
				case FVar(t, e):
					var saveMeta = f.meta;
					for (m in saveMeta) {
						if (m.name == "input") {
							hasInputs = true;
							var sel = f.name;
							var get_sel = "get_" + sel;
							var propSel = "prop_" + sel;
							var hasProperty = false;
							var isRequired = true;
							var nameInput = "input";
							if (m.params.length >= 1) {
								switch(m.params[0].expr) {
									case EConst(CString(s)):
										if (s.length > 0)
											nameInput = s;
									default:
								}
							}
							if (m.params.length >= 2) {
								switch(m.params[1].expr) {
									case EConst(CIdent(b)):
										if (b == "true") {
											hasProperty = true;
											fields.push({
												name: propSel,
												access: [Access.APrivate],
												kind: FieldType.FVar(macro:Float),
												pos: Context.currentPos(),
												meta: [{name: "prop", params: [{expr: EConst(CString("macro")), pos: Context.currentPos() }], pos: Context.currentPos()}]
											});
										}
									default:
								}
							}
							if (m.params.length >= 3) {
								switch(m.params[2].expr) {
									case EConst(CIdent(b)):
										if (b == "false") {
											isRequired = false;
										}
									default:
								}
							}
							if (hasProperty) {
								var sfields = macro class {
									inline function $get_sel() : NodeVar {
										var input = getInput($v{sel});
										if (input == null)
											return new NodeVar(new hrt.shgraph.nodes.FloatConst($i{propSel}), "output");
										else
											return getInput($v{sel});
									}
								};
								for( field in sfields.fields )
									fields.push(field);
							} else {
								var sfields = macro class {
									inline function $get_sel() : NodeVar return getInput($v{sel});
								};
								for( field in sfields.fields )
									fields.push(field);
							}
							if (e == null)
								Context.error('Input ${sel} has not affectation', f.pos);

							var enumValue = ["ShaderType", "SType", e.toString().split(".").pop()];
							mapInputs.push(macro $v{sel} => { name : $v{nameInput}, type : ${enumValue.toFieldExpr()}, hasProperty: $v{hasProperty}, isRequired : $v{isRequired} });
							f.kind = FProp("get", "null", TPath({ pack: ["hrt", "shgraph"], name: "NodeVar" }));
							f.meta = saveMeta;
							inputsList.push(f.name);

							break;
						} else if (m.name == "output") {
							hasOutputs = true;
							var sel = f.name;
							var get_sel = "get_" + sel;
							var sfields = macro class {
								inline function $get_sel() : TVar return getOutput($v{sel});
							};
							for( field in sfields.fields )
								fields.push(field);
							if (e == null)
								Context.error('Output ${sel} has not affectation', f.pos);
							var nameOutput = "";
							if (m.params.length > 0) {
								switch(m.params[0].expr) {
									case EConst(CString(s)):
										if (s.length > 0)
											nameOutput = s;
									default:
								}
							}
							var enumValue = ["ShaderType", "SType", e.toString().split(".").pop()];
							mapOutputs.push(macro $v{sel} => { name : $v{nameOutput}, type : ${enumValue.toFieldExpr()} });
							f.kind = FProp("get", "null", TPath({ pack: [], name: "TVar" }));
							f.meta = saveMeta;
							outputsList.push(f.name);

							break;
						}
					}
				default:
			}
		}
		if (hasInputs) {
			fields.push({
				name: "inputsInfo",
				access: [Access.APrivate],
				kind: FieldType.FVar(macro:Map<String, ShaderNode.InputInfo>, macro $a{mapInputs}),
				pos: Context.currentPos(),
			});
			var sfields = macro class {
				override public function getInputInfo(key : String) : ShaderNode.InputInfo return inputsInfo.get(key);
				override public function getInputInfoKeys() : Array<String> return $v{inputsList};
			};
			for( field in sfields.fields )
				fields.push(field);
		}
		if (hasOutputs) {
			fields.push({
				name: "outputsInfo",
				access: [Access.APrivate],
				kind: FieldType.FVar(macro:Map<String, ShaderNode.OutputInfo>, macro $a{mapOutputs}),
				pos: Context.currentPos(),
			});
			var sfields = macro class {
				override public function getOutputInfo(key : String) : ShaderNode.OutputInfo return outputsInfo.get(key);
				override public function getOutputInfoKeys() : Array<String> return $v{outputsList};
			};
			for( field in sfields.fields )
				fields.push(field);
		}

		var thisClass = Context.getLocalClass();
		var cl = thisClass.get();
		var clPath = cl.pack.copy();
		clPath.push(cl.name);

		#if editor
		fields.push({
			name: "_",
			access: [Access.AStatic],
			kind: FieldType.FVar(macro:Bool, macro ShaderNode.register($v{cl.name}, ${clPath.toFieldExpr()})),
			pos: Context.currentPos(),
		});
		#end

		return fields;
	}

#end
}