/*
 * Copyright 2000-2012 JetBrains s.r.o.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.intellij.codeInsight.daemon.impl.quickfix;

import com.intellij.codeInsight.FileModificationService;
import com.intellij.codeInsight.TargetElementUtil;
import com.intellij.codeInsight.daemon.QuickFixBundle;
import com.intellij.codeInsight.daemon.impl.analysis.JavaHighlightUtil;
import com.intellij.codeInsight.intention.IntentionAction;
import com.intellij.find.FindManager;
import com.intellij.find.findUsages.FindUsagesHandler;
import com.intellij.find.findUsages.FindUsagesManager;
import com.intellij.find.findUsages.JavaMethodFindUsagesOptions;
import com.intellij.find.impl.FindManagerImpl;
import com.intellij.ide.util.SuperMethodWarningUtil;
import com.intellij.openapi.application.ApplicationManager;
import com.intellij.openapi.command.CommandProcessor;
import com.intellij.openapi.command.undo.UndoUtil;
import com.intellij.openapi.diagnostic.Logger;
import com.intellij.openapi.editor.Editor;
import com.intellij.openapi.progress.ProgressManager;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.util.text.StringUtil;
import com.intellij.psi.*;
import com.intellij.psi.codeStyle.JavaCodeStyleManager;
import com.intellij.psi.codeStyle.SuggestedNameInfo;
import com.intellij.psi.codeStyle.VariableKind;
import com.intellij.psi.util.PsiUtil;
import com.intellij.psi.util.TypeConversionUtil;
import com.intellij.refactoring.RefactoringBundle;
import com.intellij.refactoring.changeSignature.ChangeSignatureProcessor;
import com.intellij.refactoring.changeSignature.JavaChangeSignatureDialog;
import com.intellij.refactoring.changeSignature.ParameterInfoImpl;
import com.intellij.refactoring.util.RefactoringUtil;
import com.intellij.usageView.UsageInfo;
import com.intellij.util.ArrayUtil;
import com.intellij.util.IncorrectOperationException;
import com.intellij.util.Processor;
import org.jetbrains.annotations.NonNls;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

import java.util.*;

/**
 * @author cdr
 * @since Nov 13, 2002
 */
public class ChangeMethodSignatureFromUsageFix implements IntentionAction/*, HighPriorityAction*/ {
  final PsiMethod myTargetMethod;
  final PsiExpression[] myExpressions;
  final PsiSubstitutor mySubstitutor;
  final PsiElement myContext;
  private final boolean myChangeAllUsages;
  private final int myMinUsagesNumberToShowDialog;
  ParameterInfoImpl[] myNewParametersInfo;
  private static final Logger LOG = Logger.getInstance(ChangeMethodSignatureFromUsageFix.class);

  public ChangeMethodSignatureFromUsageFix(@NotNull PsiMethod targetMethod,
                                           @NotNull PsiExpression[] expressions,
                                           @NotNull PsiSubstitutor substitutor,
                                           @NotNull PsiElement context,
                                           boolean changeAllUsages, int minUsagesNumberToShowDialog) {
    myTargetMethod = targetMethod;
    myExpressions = expressions;
    mySubstitutor = substitutor;
    myContext = context;
    myChangeAllUsages = changeAllUsages;
    myMinUsagesNumberToShowDialog = minUsagesNumberToShowDialog;
  }

  @Override
  @NotNull
  public String getText() {
    final String shortText = getShortText();
    if (shortText != null) return shortText;
    return QuickFixBundle.message("change.method.signature.from.usage.text",
                                  JavaHighlightUtil.formatMethod(myTargetMethod),
                                  myTargetMethod.getName(),
                                  formatTypesList(myNewParametersInfo, myContext));
  }

  @Nullable
  private String getShortText() {
    final StringBuilder buf = new StringBuilder();
    final HashSet<ParameterInfoImpl> newParams = new HashSet<ParameterInfoImpl>();
    final HashSet<ParameterInfoImpl> removedParams = new HashSet<ParameterInfoImpl>();
    final HashSet<ParameterInfoImpl> changedParams = new HashSet<ParameterInfoImpl>();
    getNewParametersInfo(myExpressions, myTargetMethod, mySubstitutor, buf, newParams, removedParams, changedParams);

    final String targetMethodName = myTargetMethod.getName();
    if (myTargetMethod.getContainingClass().findMethodsByName(targetMethodName, true).length == 1) {
      if (newParams.size() == 1) {
        final ParameterInfoImpl p = newParams.iterator().next();
        return QuickFixBundle.message("add.parameter.from.usage.text", p.getTypeText(), (ArrayUtil.find(myNewParametersInfo, p) + 1), targetMethodName);
      }
      if (removedParams.size() == 1) {
        final ParameterInfoImpl p = removedParams.iterator().next();
        return QuickFixBundle.message("remove.parameter.from.usage.text", (p.getOldIndex() + 1), targetMethodName);
      }
      if (changedParams.size() == 1) {
        final ParameterInfoImpl p = changedParams.iterator().next();
        return QuickFixBundle.message("change.parameter.from.usage.text", (p.getOldIndex() + 1), targetMethodName, myTargetMethod.getParameterList().getParameters()[p.getOldIndex()].getType().getPresentableText(),  p.getTypeText());
      }
    }
    return "<html> Change signature of " + targetMethodName + "(" + buf.toString() + ")</html>";
  }

  @Nullable
  private static String formatTypesList(ParameterInfoImpl[] infos, PsiElement context) {
    if (infos == null) return null;
    StringBuilder result = new StringBuilder();
    try {
      for (ParameterInfoImpl info : infos) {
        PsiType type = info.createType(context, context.getManager());
        if (type == null) return null;
        if (result.length() != 0) result.append(", ");
        result.append(type.getPresentableText());
      }
      return result.toString();
    }
    catch (IncorrectOperationException e) {
      return null;
    }
  }

  @Override
  @NotNull
  public String getFamilyName() {
    return QuickFixBundle.message("change.method.signature.from.usage.family");
  }

  @Override
  public boolean isAvailable(@NotNull Project project, Editor editor, PsiFile file) {
    if (!myTargetMethod.isValid() || myTargetMethod.getContainingClass() == null) return false;
    for (PsiExpression expression : myExpressions) {
      if (!expression.isValid()) return false;
    }
    if (!mySubstitutor.isValid()) return false;

    myNewParametersInfo = getNewParametersInfo(myExpressions, myTargetMethod, mySubstitutor);
    if (myNewParametersInfo == null || formatTypesList(myNewParametersInfo, myContext) == null) return false;
    return !isMethodSignatureExists();
  }

  public boolean isMethodSignatureExists() {
    PsiClass target = myTargetMethod.getContainingClass();
    LOG.assertTrue(target != null);
    PsiMethod[] methods = target.findMethodsByName(myTargetMethod.getName(), false);
    for (PsiMethod method : methods) {
      if (PsiUtil.isApplicable(method, PsiSubstitutor.EMPTY, myExpressions)) return true;
    }
    return false;
  }

  @Override
  public void invoke(@NotNull final Project project, Editor editor, final PsiFile file) {
    if (!FileModificationService.getInstance().prepareFileForWrite(file)) return;

    final PsiMethod method = SuperMethodWarningUtil.checkSuperMethod(myTargetMethod, RefactoringBundle.message("to.refactor"));
    if (method == null) return;
    myNewParametersInfo = getNewParametersInfo(myExpressions, myTargetMethod, mySubstitutor);

    final List<ParameterInfoImpl> parameterInfos =
      performChange(project, editor, file, method, myMinUsagesNumberToShowDialog, myNewParametersInfo, myChangeAllUsages, false);
    if (parameterInfos != null) {
      myNewParametersInfo = parameterInfos.toArray(new ParameterInfoImpl[parameterInfos.size()]);
    }
  }

  public static List<ParameterInfoImpl> performChange(final Project project,
                                                      final Editor editor,
                                                      final PsiFile file,
                                                      final PsiMethod method,
                                                      final int minUsagesNumber,
                                                      final ParameterInfoImpl[] newParametersInfo,
                                                      final boolean changeAllUsages,
                                                      final boolean allowDelegation) {
    if (!FileModificationService.getInstance().prepareFileForWrite(method.getContainingFile())) return null;
    final FindUsagesManager findUsagesManager = ((FindManagerImpl)FindManager.getInstance(project)).getFindUsagesManager();
    final FindUsagesHandler handler = findUsagesManager.getFindUsagesHandler(method, false);
    if (handler == null) return null;//on failure or cancel (e.g. cancel of super methods dialog)

    final JavaMethodFindUsagesOptions options = new JavaMethodFindUsagesOptions(project);
    options.isImplementingMethods = true;
    options.isOverridingMethods = true;
    options.isUsages = true;
    options.isSearchForTextOccurrences = false;
    final int[] usagesFound = new int[1];
    Runnable runnable = new Runnable() {
      @Override
      public void run() {
        Processor<UsageInfo> processor = new Processor<UsageInfo>() {
          @Override
          public boolean process(final UsageInfo t) {
            return ++usagesFound[0] < minUsagesNumber;
          }
        };

        handler.processElementUsages(method, processor, options);
      }
    };
    String progressTitle = QuickFixBundle.message("searching.for.usages.progress.title");
    if (!ProgressManager.getInstance().runProcessWithProgressSynchronously(runnable, progressTitle, true, project)) return null;

    if (ApplicationManager.getApplication().isUnitTestMode() || usagesFound[0] < minUsagesNumber) {
      ChangeSignatureProcessor processor = new ChangeSignatureProcessor(
                            project,
                            method,
                            false, null,
                            method.getName(),
                            method.getReturnType(),
                            newParametersInfo){
        @Override
        @NotNull
        protected UsageInfo[] findUsages() {
          return changeAllUsages ? super.findUsages() : UsageInfo.EMPTY_ARRAY;
        }

        @Override
        protected void performRefactoring(UsageInfo[] usages) {
          CommandProcessor.getInstance().setCurrentCommandName(getCommandName());
          super.performRefactoring(usages);
        }
      };
      processor.run();
      ApplicationManager.getApplication().runWriteAction(new Runnable() {
        @Override
        public void run() {
          UndoUtil.markPsiFileForUndo(file);
        }
      });
    }
    else {
      final List<ParameterInfoImpl> parameterInfos = newParametersInfo != null
                                                     ? new ArrayList<ParameterInfoImpl>(Arrays.asList(newParametersInfo))
                                                     : new ArrayList<ParameterInfoImpl>();
      final PsiReferenceExpression refExpr = TargetElementUtil.findReferenceExpression(editor);
      JavaChangeSignatureDialog dialog = JavaChangeSignatureDialog.createAndPreselectNew(project, method, parameterInfos, allowDelegation, refExpr);
      dialog.setParameterInfos(parameterInfos);
      dialog.show();
      return dialog.getParameters();
    }
    return null;
  }

  public static String getNewParameterNameByOldIndex(int oldIndex, final ParameterInfoImpl[] parametersInfo) {
    if (parametersInfo == null) return null;
    for (ParameterInfoImpl info : parametersInfo) {
      if (info.oldParameterIndex == oldIndex) {
        return info.getName();
      }
    }
    return null;
  }

  protected ParameterInfoImpl[] getNewParametersInfo(PsiExpression[] expressions,
                                                     PsiMethod targetMethod,
                                                     PsiSubstitutor substitutor) {
    return getNewParametersInfo(expressions, targetMethod, substitutor, new StringBuilder(), new HashSet<ParameterInfoImpl>(), new HashSet<ParameterInfoImpl>(), new HashSet<ParameterInfoImpl>());
  }

  private ParameterInfoImpl[] getNewParametersInfo(PsiExpression[] expressions,
                                                   PsiMethod targetMethod,
                                                   PsiSubstitutor substitutor,
                                                   final StringBuilder buf,
                                                   final HashSet<ParameterInfoImpl> newParams,
                                                   final HashSet<ParameterInfoImpl> removedParams,
                                                   final HashSet<ParameterInfoImpl> changedParams) {
    PsiParameter[] parameters = targetMethod.getParameterList().getParameters();
    List<ParameterInfoImpl> result = new ArrayList<ParameterInfoImpl>();
    if (expressions.length < parameters.length) {
      // find which parameters to remove
      int ei = 0;
      int pi = 0;

      while (ei < expressions.length && pi < parameters.length) {
        PsiExpression expression = expressions[ei];
        PsiParameter parameter = parameters[pi];
        PsiType paramType = substitutor.substitute(parameter.getType());
        if (buf.length() > 0) buf.append(", ");
        final PsiType parameterType = PsiUtil.convertAnonymousToBaseType(paramType);
        final String presentableText = escapePresentableType(parameterType);
        final ParameterInfoImpl parameterInfo = new ParameterInfoImpl(pi, parameter.getName(), parameterType);
        if (TypeConversionUtil.areTypesAssignmentCompatible(paramType, expression)) {
          buf.append(presentableText);
          result.add(parameterInfo);
          pi++;
          ei++;
        }
        else {
          buf.append("<s>").append(presentableText).append("</s>");
          removedParams.add(parameterInfo);
          pi++;
        }
      }
      if (result.size() != expressions.length) return null;
      for(int i = pi; i < parameters.length; i++) {
        if (buf.length() > 0) buf.append(", ");
        buf.append("<s>").append(escapePresentableType(parameters[i].getType())).append("</s>");
        final ParameterInfoImpl parameterInfo = new ParameterInfoImpl(pi, parameters[i].getName(), parameters[i].getType());
        removedParams.add(parameterInfo);
      }
    }
    else if (expressions.length > parameters.length) {
      if (!findNewParamsPlace(expressions, targetMethod, substitutor, buf, newParams, parameters, result)) return null;
    }
    else {
      //parameter type changed
      for (int i = 0; i < parameters.length; i++) {
        if (buf.length() > 0) buf.append(", ");
        PsiParameter parameter = parameters[i];
        PsiExpression expression = expressions[i];
        PsiType paramType = substitutor.substitute(parameter.getType());
        final String presentableText = escapePresentableType(paramType);
        if (TypeConversionUtil.areTypesAssignmentCompatible(paramType, expression)) {
          result.add(new ParameterInfoImpl(i, parameter.getName(), paramType));
          buf.append(presentableText);
        }
        else {
          PsiType exprType = RefactoringUtil.getTypeByExpression(expression);
          if (exprType == null) return null;
          if (exprType instanceof PsiDisjunctionType) {
            exprType = ((PsiDisjunctionType)exprType).getLeastUpperBound();
          }
          final ParameterInfoImpl changedParameterInfo = new ParameterInfoImpl(i, parameter.getName(), exprType);
          result.add(changedParameterInfo);
          changedParams.add(changedParameterInfo);
          buf.append("<s>").append(presentableText).append("</s> <b>").append(escapePresentableType(exprType)).append("</b>");
        }
      }
      // do not perform silly refactorings
      boolean isSilly = true;
      for (int i = 0; i < result.size(); i++) {
        PsiParameter parameter = parameters[i];
        PsiType paramType = substitutor.substitute(parameter.getType());
        ParameterInfoImpl parameterInfo = result.get(i);
        String typeText = parameterInfo.getTypeText();
        if (!paramType.equalsToText(typeText) && !paramType.getPresentableText().equals(typeText)) {
          isSilly = false;
          break;
        }
      }
      if (isSilly) return null;
    }
    return result.toArray(new ParameterInfoImpl[result.size()]);
  }

  protected static String escapePresentableType(PsiType exprType) {
    return StringUtil.escapeXml(exprType.getPresentableText());
  }

  protected boolean findNewParamsPlace(PsiExpression[] expressions,
                                       PsiMethod targetMethod,
                                       PsiSubstitutor substitutor,
                                       StringBuilder buf,
                                       HashSet<ParameterInfoImpl> newParams,
                                       PsiParameter[] parameters,
                                       List<ParameterInfoImpl> result) {
    // find which parameters to introduce and where
    Set<String> existingNames = new HashSet<String>();
    for (PsiParameter parameter : parameters) {
      existingNames.add(parameter.getName());
    }
    int ei = 0;
    int pi = 0;
    PsiParameter varargParam = targetMethod.isVarArgs() ? parameters[parameters.length - 1] : null;
    while (ei < expressions.length || pi < parameters.length) {
      if (buf.length() > 0) buf.append(", ");
      PsiExpression expression = ei < expressions.length ? expressions[ei] : null;
      PsiParameter parameter = pi < parameters.length ? parameters[pi] : null;
      PsiType paramType = parameter == null ? null : substitutor.substitute(parameter.getType());
      boolean parameterAssignable = paramType != null && (expression == null || TypeConversionUtil
        .areTypesAssignmentCompatible(paramType, expression));
      if (parameterAssignable) {
        final PsiType type = parameter.getType();
        result.add(new ParameterInfoImpl(pi, parameter.getName(), type));
        buf.append(escapePresentableType(type));
        pi++;
        ei++;
      }
      else if (isArgumentInVarargPosition(expressions, ei, varargParam, substitutor)) {
        if (pi == parameters.length - 1) {
          assert varargParam != null;
          final PsiType type = varargParam.getType();
          result.add(new ParameterInfoImpl(pi, varargParam.getName(), type));
          buf.append(escapePresentableType(type));
        }
        pi++;
        ei++;
      }
      else if (expression != null) {
        if (varargParam != null && pi >= parameters.length) return false;
        PsiType exprType = RefactoringUtil.getTypeByExpression(expression);
        if (exprType == null) return false;
        if (exprType instanceof PsiDisjunctionType) {
          exprType = ((PsiDisjunctionType)exprType).getLeastUpperBound();
        }
        JavaCodeStyleManager codeStyleManager = JavaCodeStyleManager.getInstance(expression.getProject());
        String name = suggestUniqueParameterName(codeStyleManager, expression, exprType, existingNames);
        final ParameterInfoImpl newParameterInfo = new ParameterInfoImpl(-1, name, exprType, expression.getText().replace('\n', ' '));
        result.add(newParameterInfo);
        newParams.add(newParameterInfo);
        buf.append("<b>").append(escapePresentableType(exprType)).append("</b>");
        ei++;
      }
    }
    if (result.size() != expressions.length && varargParam == null) return false;
    return true;
  }

  static boolean isArgumentInVarargPosition(PsiExpression[] expressions, int ei, PsiParameter varargParam, PsiSubstitutor substitutor) {
    if (varargParam == null) return false;
    final PsiExpression expression = expressions[ei];
    if (expression == null || TypeConversionUtil.areTypesAssignmentCompatible(substitutor.substitute(((PsiEllipsisType)varargParam.getType()).getComponentType()), expression)) {
      final int lastExprIdx = expressions.length - 1;
      if (ei == lastExprIdx) return true;
      return expressions[lastExprIdx].getType() != PsiType.NULL;
    }
    return false;
  }

  static String suggestUniqueParameterName(JavaCodeStyleManager codeStyleManager,
                                           PsiExpression expression,
                                           PsiType exprType,
                                           Set<String> existingNames) {
    SuggestedNameInfo nameInfo = codeStyleManager.suggestVariableName(VariableKind.PARAMETER, null, expression, exprType);
    @NonNls String[] names = nameInfo.names;
    if (expression instanceof PsiReferenceExpression) {
      final PsiElement resolve = ((PsiReferenceExpression)expression).resolve();
      if (resolve instanceof PsiVariable) {
        final VariableKind variableKind = codeStyleManager.getVariableKind((PsiVariable)resolve);
        final String propertyName = codeStyleManager.variableNameToPropertyName(((PsiVariable)resolve).getName(), variableKind);
        final String parameterName = codeStyleManager.propertyNameToVariableName(propertyName, VariableKind.PARAMETER);
        names = ArrayUtil.mergeArrays(new String[]{parameterName}, names);
      }
    }
    if (names.length == 0) names = new String[]{"param"};
    int suffix = 0;
    while (true) {
      for (String name : names) {
        String suggested = name + (suffix == 0 ? "" : String.valueOf(suffix));
        if (existingNames.add(suggested)) {
          return suggested;
        }
      }
      suffix++;
    }
  }

  @Override
  public boolean startInWriteAction() {
    return false;
  }
}