/*
 * Copyright (C) 2012 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "config.h"
#include "DatabaseManager.h"

#include "Database.h"
#include "DatabaseCallback.h"
#include "DatabaseContext.h"
#include "DatabaseTask.h"
#include "DatabaseTracker.h"
#include "ExceptionCode.h"
#include "InspectorInstrumentation.h"
#include "Logging.h"
#include "PlatformStrategies.h"
#include "ScriptController.h"
#include "ScriptExecutionContext.h"
#include "SecurityOrigin.h"
#include "SecurityOriginData.h"
#include <wtf/NeverDestroyed.h>

namespace WebCore {

class DatabaseManager::ProposedDatabase {
public:
    ProposedDatabase(DatabaseManager&, SecurityOrigin&, const String& name, const String& displayName, unsigned long estimatedSize);
    ~ProposedDatabase();

    SecurityOrigin& origin() { return m_origin; }
    DatabaseDetails& details() { return m_details; }

private:
    DatabaseManager& m_manager;
    Ref<SecurityOrigin> m_origin;
    DatabaseDetails m_details;
};

DatabaseManager::ProposedDatabase::ProposedDatabase(DatabaseManager& manager, SecurityOrigin& origin, const String& name, const String& displayName, unsigned long estimatedSize)
    : m_manager(manager)
    , m_origin(origin.isolatedCopy())
    , m_details(name.isolatedCopy(), displayName.isolatedCopy(), estimatedSize, 0, 0, 0)
{
    m_manager.addProposedDatabase(*this);
}

inline DatabaseManager::ProposedDatabase::~ProposedDatabase()
{
    m_manager.removeProposedDatabase(*this);
}

DatabaseManager& DatabaseManager::singleton()
{
    static NeverDestroyed<DatabaseManager> instance;
    return instance;
}

void DatabaseManager::initialize(const String& databasePath)
{
    DatabaseTracker::initializeTracker(databasePath);
}

void DatabaseManager::setClient(DatabaseManagerClient* client)
{
    m_client = client;
    DatabaseTracker::singleton().setClient(client);
}

bool DatabaseManager::isAvailable()
{
    return m_databaseIsAvailable;
}

void DatabaseManager::setIsAvailable(bool available)
{
    m_databaseIsAvailable = available;
}

Ref<DatabaseContext> DatabaseManager::databaseContext(ScriptExecutionContext& context)
{
    if (auto databaseContext = context.databaseContext())
        return *databaseContext;
    return adoptRef(*new DatabaseContext(context));
}

#if LOG_DISABLED

static inline void logOpenDatabaseError(ScriptExecutionContext&, const String&)
{
}

#else

static void logOpenDatabaseError(ScriptExecutionContext& context, const String& name)
{
    LOG(StorageAPI, "Database %s for origin %s not allowed to be established", name.utf8().data(), context.securityOrigin()->toString().utf8().data());
}

#endif

ExceptionOr<Ref<Database>> DatabaseManager::openDatabaseBackend(ScriptExecutionContext& context, const String& name, const String& expectedVersion, const String& displayName, unsigned estimatedSize, bool setVersionInNewDatabase)
{
    auto backend = tryToOpenDatabaseBackend(context, name, expectedVersion, displayName, estimatedSize, setVersionInNewDatabase, FirstTryToOpenDatabase);

    if (backend.hasException()) {
        if (backend.exception().code() == QUOTA_EXCEEDED_ERR) {
            // Notify the client that we've exceeded the database quota.
            // The client may want to increase the quota, and we'll give it
            // one more try after if that is the case.
            {
                // FIXME: What guarantees context.securityOrigin() is non-null?
                ProposedDatabase proposedDatabase { *this, *context.securityOrigin(), name, displayName, estimatedSize };
                this->databaseContext(context)->databaseExceededQuota(name, proposedDatabase.details());
            }
            backend = tryToOpenDatabaseBackend(context, name, expectedVersion, displayName, estimatedSize, setVersionInNewDatabase, RetryOpenDatabase);
        }
    }

    if (backend.hasException()) {
        if (backend.exception().code() == INVALID_STATE_ERR)
            logErrorMessage(context, backend.exception().message());
        else
            logOpenDatabaseError(context, name);
    }

    return backend;
}

ExceptionOr<Ref<Database>> DatabaseManager::tryToOpenDatabaseBackend(ScriptExecutionContext& scriptContext, const String& name, const String& expectedVersion, const String& displayName, unsigned estimatedSize, bool setVersionInNewDatabase,
    OpenAttempt attempt)
{
    if (is<Document>(&scriptContext)) {
        auto* page = downcast<Document>(scriptContext).page();
        if (!page || page->usesEphemeralSession())
            return Exception { SECURITY_ERR };
    }

    if (scriptContext.isWorkerGlobalScope()) {
        ASSERT_NOT_REACHED();
        return Exception { SECURITY_ERR };
    }

    auto backendContext = this->databaseContext(scriptContext);

    ExceptionOr<void> preflightResult;
    switch (attempt) {
    case FirstTryToOpenDatabase:
        preflightResult = DatabaseTracker::singleton().canEstablishDatabase(backendContext, name, estimatedSize);
        break;
    case RetryOpenDatabase:
        preflightResult = DatabaseTracker::singleton().retryCanEstablishDatabase(backendContext, name, estimatedSize);
        break;
    }
    if (preflightResult.hasException())
        return preflightResult.releaseException();

    auto database = adoptRef(*new Database(backendContext, name, expectedVersion, displayName, estimatedSize));

    auto openResult = database->openAndVerifyVersion(setVersionInNewDatabase);
    if (openResult.hasException())
        return openResult.releaseException();

    // FIXME: What guarantees backendContext.securityOrigin() is non-null?
    DatabaseTracker::singleton().setDatabaseDetails(backendContext->securityOrigin(), name, displayName, estimatedSize);
    return WTFMove(database);
}

void DatabaseManager::addProposedDatabase(ProposedDatabase& database)
{
    std::lock_guard<Lock> lock { m_proposedDatabasesMutex };
    m_proposedDatabases.add(&database);
}

void DatabaseManager::removeProposedDatabase(ProposedDatabase& database)
{
    std::lock_guard<Lock> lock { m_proposedDatabasesMutex };
    m_proposedDatabases.remove(&database);
}

ExceptionOr<Ref<Database>> DatabaseManager::openDatabase(ScriptExecutionContext& context, const String& name, const String& expectedVersion, const String& displayName, unsigned estimatedSize, RefPtr<DatabaseCallback>&& creationCallback)
{
    ScriptController::initializeThreading();

    bool setVersionInNewDatabase = !creationCallback;
    auto openResult = openDatabaseBackend(context, name, expectedVersion, displayName, estimatedSize, setVersionInNewDatabase);
    if (openResult.hasException())
        return openResult.releaseException();

    RefPtr<Database> database = openResult.releaseReturnValue();

    auto databaseContext = this->databaseContext(context);
    databaseContext->setHasOpenDatabases();
    InspectorInstrumentation::didOpenDatabase(&context, database.copyRef(), context.securityOrigin()->host(), name, expectedVersion);

    if (database->isNew() && creationCallback.get()) {
        LOG(StorageAPI, "Scheduling DatabaseCreationCallbackTask for database %p\n", database.get());
        database->setHasPendingCreationEvent(true);
        database->m_scriptExecutionContext->postTask([creationCallback, database] (ScriptExecutionContext&) {
            creationCallback->handleEvent(database.get());
            database->setHasPendingCreationEvent(false);
        });
    }

    return database.releaseNonNull();
}

bool DatabaseManager::hasOpenDatabases(ScriptExecutionContext& context)
{
    auto databaseContext = context.databaseContext();
    return databaseContext && databaseContext->hasOpenDatabases();
}

void DatabaseManager::stopDatabases(ScriptExecutionContext& context, DatabaseTaskSynchronizer* synchronizer)
{
    auto databaseContext = context.databaseContext();
    if (!databaseContext || !databaseContext->stopDatabases(synchronizer)) {
        if (synchronizer)
            synchronizer->taskCompleted();
    }
}

String DatabaseManager::fullPathForDatabase(SecurityOrigin& origin, const String& name, bool createIfDoesNotExist)
{
    {
        std::lock_guard<Lock> lock { m_proposedDatabasesMutex };
        for (auto* proposedDatabase : m_proposedDatabases) {
            if (proposedDatabase->details().name() == name && proposedDatabase->origin().equal(&origin))
                return String();
        }
    }
    return DatabaseTracker::singleton().fullPathForDatabase(SecurityOriginData::fromSecurityOrigin(origin), name, createIfDoesNotExist);
}

DatabaseDetails DatabaseManager::detailsForNameAndOrigin(const String& name, SecurityOrigin& origin)
{
    {
        std::lock_guard<Lock> lock { m_proposedDatabasesMutex };
        for (auto* proposedDatabase : m_proposedDatabases) {
            if (proposedDatabase->details().name() == name && proposedDatabase->origin().equal(&origin)) {
                ASSERT(proposedDatabase->details().threadID() == std::this_thread::get_id() || isMainThread());
                return proposedDatabase->details();
            }
        }
    }

    return DatabaseTracker::singleton().detailsForNameAndOrigin(name, SecurityOriginData::fromSecurityOrigin(origin));
}

void DatabaseManager::logErrorMessage(ScriptExecutionContext& context, const String& message)
{
    context.addConsoleMessage(MessageSource::Storage, MessageLevel::Error, message);
}

} // namespace WebCore