content: /*
   * Copyright (C) 2015 Square, Inc.
   *
   * 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.squareup.javapoet;
  
  import static com.squareup.javapoet.Util.checkArgument;
  import static com.squareup.javapoet.Util.checkNotNull;
  import static com.squareup.javapoet.Util.checkState;
  
  import java.io.IOException;
  import java.lang.reflect.Type;
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.Iterator;
  import java.util.LinkedHashSet;
  import java.util.List;
  import java.util.Map;
  import java.util.Set;
  
  import jdkx.lang.model.SourceVersion;
  import jdkx.lang.model.element.Element;
  import jdkx.lang.model.element.ExecutableElement;
  import jdkx.lang.model.element.Modifier;
  import jdkx.lang.model.element.TypeParameterElement;
  import jdkx.lang.model.type.DeclaredType;
  import jdkx.lang.model.type.ExecutableType;
  import jdkx.lang.model.type.TypeMirror;
  import jdkx.lang.model.type.TypeVariable;
  import jdkx.lang.model.util.Types;
  
  /** A generated constructor or method declaration. */
  public final class MethodSpec {
    static final String CONSTRUCTOR = "<init>";
  
    public final String name;
    public final CodeBlock javadoc;
    public final List<AnnotationSpec> annotations;
    public final Set<Modifier> modifiers;
    public final List<TypeVariableName> typeVariables;
    public final TypeName returnType;
    public final List<ParameterSpec> parameters;
    public final boolean varargs;
    public final List<TypeName> exceptions;
    public final CodeBlock code;
    public final CodeBlock defaultValue;
  
    private MethodSpec(Builder builder) {
      CodeBlock code = builder.code.build();
      checkArgument(
          code.isEmpty() || !builder.modifiers.contains(Modifier.ABSTRACT),
          "abstract method %s cannot have code",
          builder.name);
      checkArgument(
          !builder.varargs || lastParameterIsArray(builder.parameters),
          "last parameter of varargs method %s must be an array",
          builder.name);
  
      this.name = checkNotNull(builder.name, "name == null");
      this.javadoc = builder.javadoc.build();
      this.annotations = Util.immutableList(builder.annotations);
      this.modifiers = Util.immutableSet(builder.modifiers);
      this.typeVariables = Util.immutableList(builder.typeVariables);
      this.returnType = builder.returnType;
      this.parameters = Util.immutableList(builder.parameters);
      this.varargs = builder.varargs;
      this.exceptions = Util.immutableList(builder.exceptions);
      this.defaultValue = builder.defaultValue;
      this.code = code;
    }
  
    private boolean lastParameterIsArray(List<ParameterSpec> parameters) {
      return !parameters.isEmpty()
          && TypeName.asArray((parameters.get(parameters.size() - 1).type)) != null;
    }
  
    public static Builder constructorBuilder() {
      return new Builder(CONSTRUCTOR);
    }
  
    /**
     * Returns a new method spec builder that overrides {@code method} as a member of {@code
     * enclosing}. This will resolve type parameters: for example overriding {@link
     * Comparable#compareTo} in a type that implements {@code Comparable<Movie>}, the {@code T}
     * parameter will be resolved to {@code Movie}.
     *
     * <p>This will copy its visibility modifiers, type parameters, return type, name, parameters, and
     * throws declarations. An {@link Override} annotation will be added.
     *
     * <p>Note that in JavaPoet 1.2 through 1.7 this method retained annotations from the method and
     * parameters of the overridden method. Since JavaPoet 1.8 annotations must be added separately.
     */
    public static Builder overriding(ExecutableElement method, DeclaredType enclosing, Types types) {
      ExecutableType executableType = (ExecutableType) types.asMemberOf(enclosing, method);
      List<? extends TypeMirror> resolvedParameterTypes = executableType.getParameterTypes();
      List<? extends TypeMirror> resolvedThrownTypes = executableType.getThrownTypes();
      TypeMirror resolvedReturnType = executableType.getReturnType();
  
      Builder builder = overriding(method);
      builder.returns(TypeName.get(resolvedReturnType));
      for (int i = 0, size = builder.parameters.size(); i < size; i++) {
        ParameterSpec parameter = builder.parameters.get(i);
        TypeName type = TypeName.get(resolvedParameterTypes.get(i));
        builder.parameters.set(i, parameter.toBuilder(type, parameter.name).build());
      }
      builder.exceptions.clear();
      for (int i = 0, size = resolvedThrownTypes.size(); i < size; i++) {
        builder.addException(TypeName.get(resolvedThrownTypes.get(i)));
      }
  
      return builder;
    }
  
    /**
     * Returns a new method spec builder that overrides {@code method}.
     *
     * <p>This will copy its visibility modifiers, type parameters, return type, name, parameters, and
     * throws declarations. An {@link Override} annotation will be added.
     *
     * <p>Note that in JavaPoet 1.2 through 1.7 this method retained annotations from the method and
     * parameters of the overridden method. Since JavaPoet 1.8 annotations must be added separately.
     */
    public static Builder overriding(ExecutableElement method) {
      checkNotNull(method, "method == null");
  
      Element enclosingClass = method.getEnclosingElement();
      if (enclosingClass.getModifiers().contains(Modifier.FINAL)) {
        throw new IllegalArgumentException("Cannot override method on final class " + enclosingClass);
      }
  
      Set<Modifier> modifiers = method.getModifiers();
      if (modifiers.contains(Modifier.PRIVATE)
          || modifiers.contains(Modifier.FINAL)
          || modifiers.contains(Modifier.STATIC)) {
        throw new IllegalArgumentException("cannot override method with modifiers: " + modifiers);
      }
  
      String methodName = method.getSimpleName().toString();
      MethodSpec.Builder methodBuilder = MethodSpec.methodBuilder(methodName);
  
      methodBuilder.addAnnotation(Override.class);
  
      modifiers = new LinkedHashSet<>(modifiers);
      modifiers.remove(Modifier.ABSTRACT);
      modifiers.remove(Modifier.DEFAULT);
      methodBuilder.addModifiers(modifiers);
  
      for (TypeParameterElement typeParameterElement : method.getTypeParameters()) {
        TypeVariable var = (TypeVariable) typeParameterElement.asType();
        methodBuilder.addTypeVariable(TypeVariableName.get(var));
      }
  
      methodBuilder.returns(TypeName.get(method.getReturnType()));
      methodBuilder.addParameters(ParameterSpec.parametersOf(method));
      methodBuilder.varargs(method.isVarArgs());
  
      for (TypeMirror thrownType : method.getThrownTypes()) {
        methodBuilder.addException(TypeName.get(thrownType));
      }
  
      return methodBuilder;
    }
  
    public static Builder methodBuilder(String name) {
      return new Builder(name);
    }
  
    @Override
    public int hashCode() {
      return toString().hashCode();
    }
  
    @Override
    public boolean equals(Object o) {
      if (this == o) return true;
      if (o == null) return false;
      if (getClass() != o.getClass()) return false;
      return toString().equals(o.toString());
    }
  
    @Override
    public String toString() {
      StringBuilder out = new StringBuilder();
      try {
        CodeWriter codeWriter = new CodeWriter(out);
        emit(codeWriter, "Constructor", Collections.emptySet());
        return out.toString();
      } catch (IOException e) {
        throw new AssertionError();
      }
    }
  
    void emit(CodeWriter codeWriter, String enclosingName, Set<Modifier> implicitModifiers)
        throws IOException {
      codeWriter.emitJavadoc(javadocWithParameters());
      codeWriter.emitAnnotations(annotations, false);
      codeWriter.emitModifiers(modifiers, implicitModifiers);
  
      if (!typeVariables.isEmpty()) {
        codeWriter.emitTypeVariables(typeVariables);
        codeWriter.emit(" ");
      }
  
      if (isConstructor()) {
        codeWriter.emit("$L($Z", enclosingName);
      } else {
        codeWriter.emit("$T $L($Z", returnType, name);
      }
  
      boolean firstParameter = true;
      for (Iterator<ParameterSpec> i = parameters.iterator(); i.hasNext(); ) {
        ParameterSpec parameter = i.next();
        if (!firstParameter) codeWriter.emit(",").emitWrappingSpace();
        parameter.emit(codeWriter, !i.hasNext() && varargs);
        firstParameter = false;
      }
  
      codeWriter.emit(")");
  
      if (defaultValue != null && !defaultValue.isEmpty()) {
        codeWriter.emit(" default ");
        codeWriter.emit(defaultValue);
      }
  
      if (!exceptions.isEmpty()) {
        codeWriter.emitWrappingSpace().emit("throws");
        boolean firstException = true;
        for (TypeName exception : exceptions) {
          if (!firstException) codeWriter.emit(",");
          codeWriter.emitWrappingSpace().emit("$T", exception);
          firstException = false;
        }
      }
  
      if (hasModifier(Modifier.ABSTRACT)) {
        codeWriter.emit(";\n");
      } else if (hasModifier(Modifier.NATIVE)) {
        // Code is allowed to support stuff like GWT JSNI.
        codeWriter.emit(code);
        codeWriter.emit(";\n");
      } else {
        codeWriter.emit(" {\n");
  
        codeWriter.indent();
        codeWriter.emit(code, true);
        codeWriter.unindent();
  
        codeWriter.emit("}\n");
      }
      codeWriter.popTypeVariables(typeVariables);
    }
  
    private CodeBlock javadocWithParameters() {
      CodeBlock.Builder builder = javadoc.toBuilder();
      boolean emitTagNewline = true;
      for (ParameterSpec parameterSpec : parameters) {
        if (!parameterSpec.javadoc.isEmpty()) {
          // Emit a new line before @param section only if the method javadoc is present.
          if (emitTagNewline && !javadoc.isEmpty()) builder.add("\n");
          emitTagNewline = false;
          builder.add("@param $L $L", parameterSpec.name, parameterSpec.javadoc);
        }
      }
      return builder.build();
    }
  
    public boolean hasModifier(Modifier modifier) {
      return modifiers.contains(modifier);
    }
  
    public boolean isConstructor() {
      return name.equals(CONSTRUCTOR);
    }
  
    public Builder toBuilder() {
      Builder builder = new Builder(name);
      builder.javadoc.add(javadoc);
      builder.annotations.addAll(annotations);
      builder.modifiers.addAll(modifiers);
      builder.typeVariables.addAll(typeVariables);
      builder.returnType = returnType;
      builder.parameters.addAll(parameters);
      builder.exceptions.addAll(exceptions);
      builder.code.add(code);
      builder.varargs = varargs;
      builder.defaultValue = defaultValue;
      return builder;
    }
  
    public static final class Builder {
      public final List<TypeVariableName> typeVariables = new ArrayList<>();
      public final List<AnnotationSpec> annotations = new ArrayList<>();
      public final List<Modifier> modifiers = new ArrayList<>();
      public final List<ParameterSpec> parameters = new ArrayList<>();
      private final CodeBlock.Builder javadoc = CodeBlock.builder();
      private final Set<TypeName> exceptions = new LinkedHashSet<>();
      private final CodeBlock.Builder code = CodeBlock.builder();
      public String name;
      private TypeName returnType;
      private boolean varargs;
      private CodeBlock defaultValue;
  
      private Builder(String name) {
        setName(name);
      }
  
      public Builder setName(String name) {
        checkNotNull(name, "name == null");
        checkArgument(
            name.equals(CONSTRUCTOR) || SourceVersion.isName(name), "not a valid name: %s", name);
        this.name = name;
        this.returnType = name.equals(CONSTRUCTOR) ? null : TypeName.VOID;
        return this;
      }
  
      public Builder addJavadoc(String format, Object... args) {
        javadoc.add(format, args);
        return this;
      }
  
      public Builder addJavadoc(CodeBlock block) {
        javadoc.add(block);
        return this;
      }
  
      public Builder addAnnotations(Iterable<AnnotationSpec> annotationSpecs) {
        checkArgument(annotationSpecs != null, "annotationSpecs == null");
        for (AnnotationSpec annotationSpec : annotationSpecs) {
          this.annotations.add(annotationSpec);
        }
        return this;
      }
  
      public Builder addAnnotation(AnnotationSpec annotationSpec) {
        this.annotations.add(annotationSpec);
        return this;
      }
  
      public Builder addAnnotation(Class<?> annotation) {
        return addAnnotation(ClassName.get(annotation));
      }
  
      public Builder addAnnotation(ClassName annotation) {
        this.annotations.add(AnnotationSpec.builder(annotation).build());
        return this;
      }
  
      public Builder addModifiers(Modifier... modifiers) {
        checkNotNull(modifiers, "modifiers == null");
        Collections.addAll(this.modifiers, modifiers);
        return this;
      }
  
      public Builder addModifiers(Iterable<Modifier> modifiers) {
        checkNotNull(modifiers, "modifiers == null");
        for (Modifier modifier : modifiers) {
          this.modifiers.add(modifier);
        }
        return this;
      }
  
      public Builder addTypeVariables(Iterable<TypeVariableName> typeVariables) {
        checkArgument(typeVariables != null, "typeVariables == null");
        for (TypeVariableName typeVariable : typeVariables) {
          this.typeVariables.add(typeVariable);
        }
        return this;
      }
  
      public Builder addTypeVariable(TypeVariableName typeVariable) {
        typeVariables.add(typeVariable);
        return this;
      }
  
      public Builder returns(Type returnType) {
        return returns(TypeName.get(returnType));
      }
  
      public Builder returns(TypeName returnType) {
        checkState(!name.equals(CONSTRUCTOR), "constructor cannot have return type.");
        this.returnType = returnType;
        return this;
      }
  
      public Builder addParameters(Iterable<ParameterSpec> parameterSpecs) {
        checkArgument(parameterSpecs != null, "parameterSpecs == null");
        for (ParameterSpec parameterSpec : parameterSpecs) {
          this.parameters.add(parameterSpec);
        }
        return this;
      }
  
      public Builder addParameter(Type type, String name, Modifier... modifiers) {
        return addParameter(TypeName.get(type), name, modifiers);
      }
  
      public Builder addParameter(TypeName type, String name, Modifier... modifiers) {
        return addParameter(ParameterSpec.builder(type, name, modifiers).build());
      }
  
      public Builder addParameter(ParameterSpec parameterSpec) {
        this.parameters.add(parameterSpec);
        return this;
      }
  
      public Builder varargs() {
        return varargs(true);
      }
  
      public Builder varargs(boolean varargs) {
        this.varargs = varargs;
        return this;
      }
  
      public Builder addExceptions(Iterable<? extends TypeName> exceptions) {
        checkArgument(exceptions != null, "exceptions == null");
        for (TypeName exception : exceptions) {
          this.exceptions.add(exception);
        }
        return this;
      }
  
      public Builder addException(Type exception) {
        return addException(TypeName.get(exception));
      }
  
      public Builder addException(TypeName exception) {
        this.exceptions.add(exception);
        return this;
      }
  
      public Builder addCode(String format, Object... args) {
        code.add(format, args);
        return this;
      }
  
      public Builder addNamedCode(String format, Map<String, ?> args) {
        code.addNamed(format, args);
        return this;
      }
  
      public Builder addCode(CodeBlock codeBlock) {
        code.add(codeBlock);
        return this;
      }
  
      public Builder addComment(String format, Object... args) {
        code.add("// " + format + "\n", args);
        return this;
      }
  
      public Builder defaultValue(String format, Object... args) {
        return defaultValue(CodeBlock.of(format, args));
      }
  
      public Builder defaultValue(CodeBlock codeBlock) {
        checkState(this.defaultValue == null, "defaultValue was already set");
        this.defaultValue = checkNotNull(codeBlock, "codeBlock == null");
        return this;
      }
  
      /**
       * @param codeBlock the control flow construct and its code, such as "if (foo == 5)". Shouldn't
       *     contain braces or newline characters.
       */
      public Builder beginControlFlow(CodeBlock codeBlock) {
        return beginControlFlow("$L", codeBlock);
      }
  
      /**
       * @param controlFlow the control flow construct and its code, such as "if (foo == 5)".
       *     Shouldn't contain braces or newline characters.
       */
      public Builder beginControlFlow(String controlFlow, Object... args) {
        code.beginControlFlow(controlFlow, args);
        return this;
      }
  
      /**
       * @param codeBlock the control flow construct and its code, such as "else if (foo == 10)".
       *     Shouldn't contain braces or newline characters.
       */
      public Builder nextControlFlow(CodeBlock codeBlock) {
        return nextControlFlow("$L", codeBlock);
      }
  
      /**
       * @param controlFlow the control flow construct and its code, such as "else if (foo == 10)".
       *     Shouldn't contain braces or newline characters.
       */
      public Builder nextControlFlow(String controlFlow, Object... args) {
        code.nextControlFlow(controlFlow, args);
        return this;
      }
  
      public Builder endControlFlow() {
        code.endControlFlow();
        return this;
      }
  
      /**
       * @param codeBlock the optional control flow construct and its code, such as "while(foo ==
       *     20)". Only used for "do/while" control flows.
       */
      public Builder endControlFlow(CodeBlock codeBlock) {
        return endControlFlow("$L", codeBlock);
      }
  
      /**
       * @param controlFlow the optional control flow construct and its code, such as "while(foo ==
       *     20)". Only used for "do/while" control flows.
       */
      public Builder endControlFlow(String controlFlow, Object... args) {
        code.endControlFlow(controlFlow, args);
        return this;
      }
  
      public Builder addStatement(String format, Object... args) {
        code.addStatement(format, args);
        return this;
      }
  
      public Builder addStatement(CodeBlock codeBlock) {
        code.addStatement(codeBlock);
        return this;
      }
  
      public MethodSpec build() {
        return new MethodSpec(this);
      }
    }
  }
  