package org.ntlab.traceDebugger;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.eclipse.jdt.core.IMethod;
import org.eclipse.jdt.core.IType;
import org.eclipse.jdt.core.JavaModelException;
import org.eclipse.jface.viewers.TreeNode;
import org.ntlab.traceAnalysisPlatform.tracer.trace.MethodExecution;
import org.ntlab.traceAnalysisPlatform.tracer.trace.MethodInvocation;
import org.ntlab.traceAnalysisPlatform.tracer.trace.ObjectReference;
import org.ntlab.traceAnalysisPlatform.tracer.trace.Statement;
import org.ntlab.traceAnalysisPlatform.tracer.trace.TracePoint;

public class Variables {
	private static final Variables theInstance = new Variables();
	private List<Variable> roots = new ArrayList<>();
	public static final String RETURN_VARIABLE_NAME = "return";

	public static Variables getInstance() {
		return theInstance;
	}

	public TreeNode[] getVariablesTreeNodes() {
		TreeNode[] rootNodes = new TreeNode[roots.size()];
		if (roots.isEmpty()) {
			return rootNodes;
		}
		for (int i = 0; i < roots.size(); i++) {
			Variable rootVariableData = roots.get(i);
			createVariablesTreeNode(null, rootNodes, i, rootVariableData);
		}
		return rootNodes;
	}

	private void createVariablesTreeNode(TreeNode parentNode, TreeNode[] addingNodes, int index, Variable addingVariableData) {
		TreeNode newNode = new TreeNode(addingVariableData);
		newNode.setParent(parentNode);
		addingNodes[index] = newNode;
		TreeNode[] childNodes = new TreeNode[addingVariableData.getChildren().size()];
		addingNodes[index].setChildren(childNodes);
		for (int i = 0; i < addingVariableData.getChildren().size(); i++) {
			Variable child = addingVariableData.getChildren().get(i);
			createVariablesTreeNode(newNode, childNodes, i, child);
		}
	}

	public void updateAllObjectDataByMethodExecution(MethodExecution methodExecution) {
		if (methodExecution == null) return;			
		List<Statement> statements = methodExecution.getStatements();
		int lastOrder = statements.size() - 1;
		TracePoint tp  = methodExecution.getTracePoint(lastOrder);
		updateAllObjectData(null, tp, false);
	}

	public void updateAllObjectDataByTracePoint(TracePoint from, TracePoint to, boolean isReturned) {
		updateAllObjectData(from, to, isReturned);
	}

	private void updateAllObjectData(TracePoint from, TracePoint to, boolean isReturned) {
		resetData();
		if (from != null) updateReturnValue(from, to, isReturned);
		MethodExecution me = to.getMethodExecution();
		updateRootThisState(me, to, isReturned);
		updateArgsState(me, to, isReturned);
	}
	
	private void updateReturnValue(TracePoint from, TracePoint to, boolean isReturned) {
		Statement statement = from.getStatement();
		ObjectReference ref = null;
		MethodExecution me = null;
		if (statement instanceof MethodInvocation) {
			MethodInvocation mi = (MethodInvocation)statement;
			me = mi.getCalledMethodExecution();
			ref = mi.getCalledMethodExecution().getReturnValue();
		} else if (isReturned) {
			me = from.getMethodExecution();
			ref = me.getReturnValue();
		}
		if (ref != null) {
			String returnValueClassName = ref.getActualType();
			if (returnValueClassName.equals("void")) return;
			String returnValueId = ref.getId();
			String thisObjId = me.getThisObjId();
			String thisClassName = me.getThisClassName();
			Variable variable = new Variable(RETURN_VARIABLE_NAME, thisClassName, thisObjId, returnValueClassName, returnValueId, from, isReturned);
			roots.add(variable);
			variable.createNextHierarchyState();			
		}
	}
	
	private void updateRootThisState(MethodExecution methodExecution, TracePoint tp, boolean isReturned) {
		String thisObjId = methodExecution.getThisObjId();
		String thisClassName = methodExecution.getThisClassName();
		Variable variable = new Variable("this", null, null, thisClassName, thisObjId, tp, isReturned);
		roots.add(variable);
		variable.createNextHierarchyState();
	}

	private void updateArgsState(MethodExecution methodExecution, TracePoint tp, boolean isReturned) {
		// methodExecutionが持つargumentsを取得(ArrayList)し、そのargumentsのサイズも取得(int)
		List<ObjectReference> args = methodExecution.getArguments();
		if (args.size() > 0) {
			IType type = JavaEditorOperator.findIType(methodExecution);
			String methodSignature = methodExecution.getSignature();
			IMethod method = JavaEditorOperator.findIMethod(type, methodSignature);			
			String[] argNames = getParameterNames(method); // 引数のIMethodから仮引数名を取得する
			for (int i = 0; i < args.size(); i++) {
				String argName = (argNames.length == args.size()) ? argNames[i] : "arg" + i; // 少なくとも引数の個数が不一致のときは正しい引数名が取れていない
				ObjectReference arg = args.get(i);
				String argId = arg.getId();
				String argType = arg.getActualType();
				Variable argData = new Variable(argName, null, null, argType, argId, tp, isReturned);
				argData.createNextHierarchyState();
				roots.add(argData);
			}
		}
	}
	
	private String[] getParameterNames(IMethod method) {
		String[] argNames = new String[0];
		if (method != null) {
			try {
				argNames = method.getParameterNames();
			} catch (JavaModelException e) {
				e.printStackTrace();
			}
		}
		return argNames;
	}
	
	public void addAdditionalAttributes(final Set<String> idSet, final Map<String, Object> additionalAttributes) {
		for (Variable root : roots) {
			addAdditionalAttributes(root, idSet, additionalAttributes);
		}
	}
	
	private void addAdditionalAttributes(Variable variable, final Set<String> idSet, final Map<String, Object> additionalAttributes) {
		if (variable == null) return;
		if (idSet.contains(variable.getId())) {
			for (Map.Entry<String, Object> entry : additionalAttributes.entrySet()) {
				variable.addAdditionalAttribute(entry.getKey(), entry.getValue());	
			}			
		}
		for (Variable child : variable.getChildren()) {
			addAdditionalAttributes(child, idSet, additionalAttributes);
		}
	}
	
	public void resetData() {
		roots.clear();
	}
}