/*
MIT License

Copyright (c) 2018-2019 Gang ZHANG

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/

package depends.extractor.ruby.jruby;

import java.util.ArrayList;
import java.util.List;

import org.jrubyparser.ast.AssignableNode;
import org.jrubyparser.ast.CallNode;
import org.jrubyparser.ast.ClassVarAsgnNode;
import org.jrubyparser.ast.ClassVarDeclNode;
import org.jrubyparser.ast.Colon2Node;
import org.jrubyparser.ast.Colon3Node;
import org.jrubyparser.ast.ConstDeclNode;
import org.jrubyparser.ast.DAsgnNode;
import org.jrubyparser.ast.DefsNode;
import org.jrubyparser.ast.FCallNode;
import org.jrubyparser.ast.GlobalAsgnNode;
import org.jrubyparser.ast.INameNode;
import org.jrubyparser.ast.InstAsgnNode;
import org.jrubyparser.ast.ListNode;
import org.jrubyparser.ast.LocalAsgnNode;
import org.jrubyparser.ast.MultipleAsgnNode;
import org.jrubyparser.ast.Node;
import org.jrubyparser.ast.UnaryCallNode;
import org.jrubyparser.ast.VCallNode;

import depends.entity.ContainerEntity;
import depends.extractor.ruby.RubyBuiltInType;
import depends.extractor.ruby.RubyHandlerContext;

public class RubyParserHelper {
	private static RubyParserHelper inst = new RubyParserHelper();
	public static RubyParserHelper getInst() {
		return inst;
	}

	private RubyBuiltInType buildInType;
	
	private RubyParserHelper() {
		this.buildInType = new RubyBuiltInType();
	}
	
	
	public String getName(Node node) {
		String name = "";
		if (node instanceof INameNode) {
			name = ((INameNode)node).getName();
			if (node instanceof Colon2Node) {
				Node left = ((Colon2Node)node).getLeftNode();
				if (left!=null) {
					name = getName(left) + "."+name;
				}
			}else if (node instanceof Colon3Node) {
				name = "."+name;
			}
		}
		return name.length()>0?name:null;
	}

	public boolean isFunctionCall(Node ctx) {
		return ctx instanceof CallNode ||
				ctx instanceof FCallNode ||
				ctx instanceof UnaryCallNode ||
				ctx instanceof VCallNode;
	}
	
	public List<String> getName(AssignableNode ctx) {
		List<String> names = new ArrayList<>();
		if (ctx instanceof ClassVarAsgnNode) {
			names.add(((ClassVarAsgnNode)ctx).getName());
		}else if (ctx instanceof ClassVarDeclNode) {
			names.add(((ClassVarDeclNode)ctx).getName());
		}else if (ctx instanceof ConstDeclNode) {
			names.add(((ConstDeclNode)ctx).getName());
		}else if (ctx instanceof DAsgnNode) {
			names.add(((DAsgnNode)ctx).getName());
		}else if (ctx instanceof GlobalAsgnNode) {
			names.add(((GlobalAsgnNode)ctx).getName());
		}else if (ctx instanceof InstAsgnNode) {
			names.add(((InstAsgnNode)ctx).getName());
		}else if (ctx instanceof LocalAsgnNode) {
			names.add(((LocalAsgnNode)ctx).getName());
		}else if (ctx instanceof MultipleAsgnNode) {
			ListNode pre = ((MultipleAsgnNode)ctx).getPre();
			if (pre!=null) {
				//TODO: support multiple assignment
			}
		}
		return names;
	}

	public String getReciever(Node ctx) {
		Node receiver = null;
		if (ctx instanceof CallNode) {
			receiver = ((CallNode)ctx).getReceiver();
		}else if (ctx instanceof DefsNode) {
			receiver = ((DefsNode)ctx).getReceiver();
		}
		if (receiver==null) {
			return null;
		}
		if (receiver instanceof INameNode) {
			return this.getName(receiver);
		}
		return null;
	}

	public ContainerEntity getScopeOfVar(AssignableNode node, RubyHandlerContext context) {
		if (node instanceof LocalAsgnNode) return context.lastContainer();
		if (node instanceof InstAsgnNode) return context.currentType();
		if (node instanceof ClassVarAsgnNode) return context.currentType();
		if (node instanceof GlobalAsgnNode) return context.globalScope();
		if (node instanceof DAsgnNode) return context.lastContainer();
		return context.lastContainer();
	}

	public boolean isArithMeticOperator(String name) {
		return name.equals("+") ||
				name.equals("-") ||
				name.equals("*") ||
				name.equals("/") ||
				name.equals("**") ||
				name.equals("%") ||
				name.equals("&") ||
				name.equals("<") ||
				name.equals("<=") ||
				name.equals(">") ||
				name.equals(">=") ||
				name.equals("==") ||
				name.equals("!=") ||
				name.equals("===") ||
				name.equals("<<") ||
				name.equals(">>") ||
				name.equals("~") ||
				name.equals("!") ||
				name.equals("^");
	}
	
	public boolean isCommonOperator(String name) {
		return this.buildInType.isBuildInMethod(name);
	}
}