palemoon27/embedding/components/commandhandler/nsControllerCommandTable.cpp

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsString.h"
#include "nsIControllerCommand.h"
#include "nsControllerCommandTable.h"

nsresult NS_NewControllerCommandTable(nsIControllerCommandTable** aResult);

// this value is used to size the hash table. Just a sensible upper bound
#define NUM_COMMANDS_LENGTH 32

nsControllerCommandTable::nsControllerCommandTable()
  : mCommandsTable(NUM_COMMANDS_LENGTH)
  , mMutable(true)
{
}

nsControllerCommandTable::~nsControllerCommandTable()
{
}

NS_IMPL_ISUPPORTS(nsControllerCommandTable, nsIControllerCommandTable,
                  nsISupportsWeakReference)

NS_IMETHODIMP
nsControllerCommandTable::MakeImmutable(void)
{
  mMutable = false;
  return NS_OK;
}

NS_IMETHODIMP
nsControllerCommandTable::RegisterCommand(const char* aCommandName,
                                          nsIControllerCommand* aCommand)
{
  NS_ENSURE_TRUE(mMutable, NS_ERROR_FAILURE);

  mCommandsTable.Put(nsDependentCString(aCommandName), aCommand);

  return NS_OK;
}

NS_IMETHODIMP
nsControllerCommandTable::UnregisterCommand(const char* aCommandName,
                                            nsIControllerCommand* aCommand)
{
  NS_ENSURE_TRUE(mMutable, NS_ERROR_FAILURE);

  nsDependentCString commandKey(aCommandName);
  if (!mCommandsTable.Get(commandKey, nullptr)) {
    return NS_ERROR_FAILURE;
  }

  mCommandsTable.Remove(commandKey);
  return NS_OK;
}

NS_IMETHODIMP
nsControllerCommandTable::FindCommandHandler(const char* aCommandName,
                                             nsIControllerCommand** aResult)
{
  NS_ENSURE_ARG_POINTER(aResult);

  *aResult = nullptr;

  nsCOMPtr<nsIControllerCommand> foundCommand;
  mCommandsTable.Get(nsDependentCString(aCommandName),
                     getter_AddRefs(foundCommand));
  if (!foundCommand) {
    return NS_ERROR_FAILURE;
  }

  foundCommand.forget(aResult);
  return NS_OK;
}

NS_IMETHODIMP
nsControllerCommandTable::IsCommandEnabled(const char* aCommandName,
                                           nsISupports* aCommandRefCon,
                                           bool* aResult)
{
  NS_ENSURE_ARG_POINTER(aResult);

  *aResult = false;

  nsCOMPtr<nsIControllerCommand> commandHandler;
  FindCommandHandler(aCommandName, getter_AddRefs(commandHandler));
  if (!commandHandler) {
    NS_WARNING("Controller command table asked about a command that it does "
               "not handle");
    return NS_OK;
  }

  return commandHandler->IsCommandEnabled(aCommandName, aCommandRefCon,
                                          aResult);
}

NS_IMETHODIMP
nsControllerCommandTable::UpdateCommandState(const char* aCommandName,
                                             nsISupports* aCommandRefCon)
{
  nsCOMPtr<nsIControllerCommand> commandHandler;
  FindCommandHandler(aCommandName, getter_AddRefs(commandHandler));
  if (!commandHandler) {
    NS_WARNING("Controller command table asked to update the state of a "
               "command that it does not handle");
    return NS_OK;
  }

  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP
nsControllerCommandTable::SupportsCommand(const char* aCommandName,
                                          nsISupports* aCommandRefCon,
                                          bool* aResult)
{
  NS_ENSURE_ARG_POINTER(aResult);

  // XXX: need to check the readonly and disabled states

  *aResult = false;

  nsCOMPtr<nsIControllerCommand> commandHandler;
  FindCommandHandler(aCommandName, getter_AddRefs(commandHandler));

  *aResult = (commandHandler.get() != nullptr);
  return NS_OK;
}

NS_IMETHODIMP
nsControllerCommandTable::DoCommand(const char* aCommandName,
                                    nsISupports* aCommandRefCon)
{
  nsCOMPtr<nsIControllerCommand> commandHandler;
  FindCommandHandler(aCommandName, getter_AddRefs(commandHandler));
  if (!commandHandler) {
    NS_WARNING("Controller command table asked to do a command that it does "
               "not handle");
    return NS_OK;
  }

  return commandHandler->DoCommand(aCommandName, aCommandRefCon);
}

NS_IMETHODIMP
nsControllerCommandTable::DoCommandParams(const char* aCommandName,
                                          nsICommandParams* aParams,
                                          nsISupports* aCommandRefCon)
{
  nsCOMPtr<nsIControllerCommand> commandHandler;
  FindCommandHandler(aCommandName, getter_AddRefs(commandHandler));
  if (!commandHandler) {
    NS_WARNING("Controller command table asked to do a command that it does "
               "not handle");
    return NS_OK;
  }
  return commandHandler->DoCommandParams(aCommandName, aParams, aCommandRefCon);
}

NS_IMETHODIMP
nsControllerCommandTable::GetCommandState(const char* aCommandName,
                                          nsICommandParams* aParams,
                                          nsISupports* aCommandRefCon)
{
  nsCOMPtr<nsIControllerCommand> commandHandler;
  FindCommandHandler(aCommandName, getter_AddRefs(commandHandler));
  if (!commandHandler) {
    NS_WARNING("Controller command table asked to do a command that it does "
               "not handle");
    return NS_OK;
  }
  return commandHandler->GetCommandStateParams(aCommandName, aParams,
                                               aCommandRefCon);
}

static PLDHashOperator
AddCommand(const nsACString& aKey, nsIControllerCommand* aData, void* aArg)
{
  // aArg is a pointer to a array of strings. It gets incremented after
  // allocating each one so that it points to the next location for AddCommand
  // to assign a string to.
  char*** commands = static_cast<char***>(aArg);
  (**commands) = ToNewCString(aKey);
  (*commands)++;
  return PL_DHASH_NEXT;
}

NS_IMETHODIMP
nsControllerCommandTable::GetSupportedCommands(uint32_t* aCount,
                                               char*** aCommands)
{
  char** commands =
    static_cast<char**>(NS_Alloc(sizeof(char*) * mCommandsTable.Count()));
  *aCount = mCommandsTable.Count();
  *aCommands = commands;

  mCommandsTable.EnumerateRead(AddCommand, &commands);
  return NS_OK;
}

nsresult
NS_NewControllerCommandTable(nsIControllerCommandTable** aResult)
{
  NS_PRECONDITION(aResult != nullptr, "null ptr");
  if (!aResult) {
    return NS_ERROR_NULL_POINTER;
  }

  nsControllerCommandTable* newCommandTable = new nsControllerCommandTable();
  NS_ADDREF(newCommandTable);
  *aResult = newCommandTable;
  return NS_OK;
}