// Copyright 2015 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/renderer/java/gin_java_function_invocation_helper.h"

#include <utility>

#include "base/strings/strcat.h"
#include "base/values.h"
#include "content/common/android/gin_java_bridge_errors.h"
#include "content/common/android/gin_java_bridge_value.h"
#include "content/public/renderer/v8_value_converter.h"
#include "content/renderer/java/gin_java_bridge_object.h"
#include "content/renderer/java/gin_java_bridge_value_converter.h"
#include "v8/include/v8-exception.h"

namespace content {

namespace {

const char kMethodInvocationAsConstructorDisallowed[] =
    "Java bridge method can't be invoked as a constructor";
const char kMethodInvocationOnNonInjectedObjectDisallowed[] =
    "Java bridge method can't be invoked on a non-injected object";
const char kMethodInvocationErrorMessage[] =
    "Java bridge method invocation error";

}  // namespace

GinJavaFunctionInvocationHelper::GinJavaFunctionInvocationHelper(
    const std::string& method_name,
    const base::WeakPtr<GinJavaBridgeDispatcher>& dispatcher)
    : method_name_(method_name),
      dispatcher_(dispatcher),
      converter_(new GinJavaBridgeValueConverter()) {}

GinJavaFunctionInvocationHelper::~GinJavaFunctionInvocationHelper() {
}

v8::Local<v8::Value> GinJavaFunctionInvocationHelper::Invoke(
    gin::Arguments* args) {
  if (!dispatcher_) {
    args->isolate()->ThrowException(v8::Exception::Error(gin::StringToV8(
        args->isolate(), base::StrCat({"Error invoking ", method_name_, ": ",
                                       kMethodInvocationErrorMessage}))));
    return v8::Undefined(args->isolate());
  }

  if (args->IsConstructCall()) {
    args->isolate()->ThrowException(v8::Exception::Error(gin::StringToV8(
        args->isolate(),
        base::StrCat({"Error invoking ", method_name_, ": ",
                      kMethodInvocationAsConstructorDisallowed}))));
    return v8::Undefined(args->isolate());
  }

  content::GinJavaBridgeObject* object = nullptr;
  if (!args->GetHolder(&object) || !object) {
    args->isolate()->ThrowException(v8::Exception::Error(gin::StringToV8(
        args->isolate(),
        base::StrCat({"Error invoking ", method_name_, ": ",
                      kMethodInvocationOnNonInjectedObjectDisallowed}))));
    return v8::Undefined(args->isolate());
  }

  base::Value::List arguments;
  {
    v8::HandleScope handle_scope(args->isolate());
    v8::Local<v8::Context> context = args->isolate()->GetCurrentContext();
    v8::Local<v8::Value> val;
    while (args->GetNext(&val)) {
      std::unique_ptr<base::Value> arg(converter_->FromV8Value(val, context));
      if (arg) {
        arguments.Append(base::Value::FromUniquePtrValue(std::move(arg)));
      } else {
        arguments.Append(base::Value());
      }
    }
  }

  mojom::GinJavaBridgeError error =
      mojom::GinJavaBridgeError::kGinJavaBridgeNoError;

  std::unique_ptr<base::Value> result;
  if (auto* remote = object->GetRemote()) {
    base::Value::List result_wrapper;
    if (remote->InvokeMethod(method_name_, std::move(arguments), &error,
                             &result_wrapper)) {
      if (!result_wrapper.empty()) {
        result = base::Value::ToUniquePtrValue(result_wrapper[0].Clone());
      }
    } else {
      error = mojom::GinJavaBridgeError::kGinJavaBridgeObjectIsGone;
    }
  }
  if (!result.get()) {
    args->isolate()->ThrowException(v8::Exception::Error(gin::StringToV8(
        args->isolate(), base::StrCat({"Error invoking ", method_name_, ": ",
                                       GinJavaBridgeErrorToString(error)}))));
    return v8::Undefined(args->isolate());
  }
  if (!result->is_blob()) {
    return converter_->ToV8Value(result.get(),
                                 args->isolate()->GetCurrentContext());
  }

  std::unique_ptr<const GinJavaBridgeValue> gin_value =
      GinJavaBridgeValue::FromValue(result.get());
  if (gin_value->IsType(GinJavaBridgeValue::TYPE_OBJECT_ID)) {
    GinJavaBridgeObject* object_result = nullptr;
    GinJavaBridgeDispatcher::ObjectID object_id;
    if (gin_value->GetAsObjectID(&object_id)) {
      object_result = dispatcher_->GetObject(object_id);
    }
    if (object_result) {
      v8::Local<v8::Value> controller;
      if (!object_result->GetWrapper(args->isolate()).ToLocal(&controller)) {
        return v8::Undefined(args->isolate());
      }
      return controller;
    }
  } else if (gin_value->IsType(GinJavaBridgeValue::TYPE_NONFINITE)) {
    float float_value;
    gin_value->GetAsNonFinite(&float_value);
    return v8::Number::New(args->isolate(), float_value);
  }
  return v8::Undefined(args->isolate());
}

}  // namespace content