/*

* Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

*

* This program is free software: you can redistribute it and/or modify

* it under the terms of the GNU Lesser General Public License as published by

* the Free Software Foundation, version 2.1 of the License.

* 

* This program is distributed in the hope that it will be useful,

* but WITHOUT ANY WARRANTY; without even the implied warranty of

* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

* GNU Lesser General Public License for more details.

*

* You should have received a copy of the GNU Lesser General Public License

* along with this program.  If not, 

* see "http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html/".

*

* Description: This implements the bookmarks API's.

*

*/

#include<QString>

#include<QFile>

#include<QFileInfo>

#include<QDebug>

#include<QSqlDatabase>

#include<QSqlQuery>

#include<QSqlError>

#include<QWidget>

#include<QtGui>

#include "bookmarksapi.h"

#include "BookmarksManager.h"

#include "BookmarkFav.h"

#include "BookmarkResults.h"

#include "TagResults.h"

#include "xbelreader.h"

#include "xbelwriter.h"

#include "defaultBookmarks.xml.h"

BookmarksManager::BookmarksManager(QWidget *parent) :

    QObject(parent)

{

    setObjectName("bookmarksManager");

    m_db = QSqlDatabase::database(BOOKMARKS_DB_NAME);

    if (!m_db.isValid()) {

        m_db = QSqlDatabase::addDatabase("QSQLITE", BOOKMARKS_DB_NAME);

        m_db.setDatabaseName(BOOKMARKS_DB_FILE);

    }

    if (m_db.open()) {

        // TODO: Do we need a flag so that this gets called only once OR when

        // creating a database tables "IF NOT EXISTS" is good enough

        createBookmarksSchema();

    }

}

BookmarksManager::~BookmarksManager() {

    m_db.close();

    QSqlDatabase::removeDatabase(BOOKMARKS_DB_NAME);

}

/*

 * +-------------+       +----------+

 * |Bookmarks(ID)|* <-> *|Tags(BMID)|

 * +-------------+       +----------+

 */

void BookmarksManager::createBookmarksSchema() {

    // Bookmarks

    if (!doQuery("CREATE TABLE IF NOT EXISTS bookmarks("

                    "id INTEGER PRIMARY KEY,"

                    "title text, "

                    "url text,"

                    "sortIndex int DEFAULT 0)")) {

        // TODO: do some error handling here!

        return;

    }

    // Make sorting faster

    if (!doQuery("CREATE INDEX IF NOT EXISTS bm_sort_idx ON bookmarks(sortIndex ASC)")) {

        // TODO: do some error handling here!

        return;

    }

    // We do a lot of lookups by id

    if (!doQuery("CREATE INDEX IF NOT EXISTS bm_id_idx ON bookmarks(id ASC)")) {

        // TODO: do some error handling here!

        return;

    }

    // Tags

    // Note: foreign key constraints are not enforced in the current version of sqlite

    // that we are using.

    if (!doQuery("CREATE TABLE IF NOT EXISTS tags("

                    "bmid INTEGER,"

                    "tag text,"

                    "FOREIGN KEY(bmid) REFERENCES bookmarks(id))")) {

        // TODO: do some error handling here!

        return;

    }

    // We do a lot of lookups, both by bookmark id and by tag

    if (!doQuery("CREATE INDEX IF NOT EXISTS tags_bmid_idx ON tags(bmid ASC)")) {

        // TODO: do some error handling here!

        return;

    }

    if (!doQuery("CREATE INDEX IF NOT EXISTS tags_tag_idx ON tags(tag ASC)")) {

        // TODO: do some error handling here!

        return;

    }

}

// TODO refactor this - nothing except the schema creation can use it as is

bool BookmarksManager::doQuery(QString query) {

#ifdef ENABLE_PERF_TRACE

    PERF_DEBUG() << __PRETTY_FUNCTION__ << query << "\n";

    unsigned int st = WrtPerfTracer::tracer()->startTimer();

#endif

    QSqlQuery db_query(m_db);

    bool ok = db_query.exec(query);

    if (!ok) {

        qDebug() << "BookmarksManager::doQuery" << QString("ERR: %1 %2").arg(db_query.lastError().type()).arg(db_query.lastError().text()) << " Query: " << db_query.lastQuery();

    }

#ifdef ENABLE_PERF_TRACE

    PERF_DEBUG() << __PRETTY_FUNCTION__ << WrtPerfTracer::tracer()->elapsedTime(st) << "\n";

#endif

    return ok;   

}

/**==============================================================

 * Description: Normalize a given url, if needed.

 * It adds http:// in front, if the url is relative.

 ================================================================*/

QString BookmarksManager::normalizeUrl(const QString& url)

{

    // If the URL is relative, add http in front

    QString updatedUrl = url;

    if (!url.contains("://")) {

        updatedUrl.prepend("http://");

    }

    return updatedUrl;

}

/**==============================================================

 * Description: Adds the bookmark to the database, given title and

 * url. 

 * Returns: Returns bookmarkID ( >0)else Failure (-1 or -2)

 ================================================================*/

int BookmarksManager::addBookmark(QString title, QString URL)

{

    int bookmarkId = 0;

    if(URL.isEmpty()) {

       bookmarkId = FAILURE;

    }

    if(bookmarkId != FAILURE) {

        // do some checking on parameters

        QString updatedTitle = title;

        QString updatedUrl = normalizeUrl(URL);

        int soIndex = 1;

        if (title.isEmpty()) {

            updatedTitle = "Untitled";

        }

        if (m_db.isOpen()) {

            QSqlQuery query(m_db);

            m_db.transaction();

            if (!query.exec("SELECT count(*) from bookmarks")) {

                lastErrMsg(query);

                m_db.rollback();

                return DATABASEERROR;

            }

            if(query.next()) {

                query.prepare("UPDATE bookmarks SET sortIndex=sortIndex+1 WHERE sortIndex >= :sIndex");

                query.bindValue(":sIndex", soIndex);

                if (!query.exec()) {

                    lastErrMsg(query);

                    m_db.rollback();

                    return DATABASEERROR;

                 }

           } 

           query.prepare("INSERT INTO bookmarks (title, url, sortIndex) "

                               "VALUES (:title, :url, :sIndex)");

            query.bindValue(":title", QVariant(updatedTitle));

            query.bindValue(":url",    QVariant(updatedUrl));

            query.bindValue(":sIndex",  QVariant(soIndex));

            if (!query.exec()) {

                lastErrMsg(query);

                m_db.rollback();

                return DATABASEERROR;

           }

           // Note: lastInsertId() is not thread-safe

            bookmarkId = query.lastInsertId().toInt();

            if (!m_db.commit()) {

                qDebug() << m_db.lastError().text();

                m_db.rollback();

               return DATABASEERROR;

            }

        } else {

            bookmarkId = FAILURE;

        }

      }

    return bookmarkId;

}

/**==============================================================

 * Import bookmarks from an XBEL file. If no filename is 

 * passed in a set of default bookmarks will be imported.

 * The default bookmarks used can be changed by updating

 * the file "defaultBookmarks.xml.cpp".

 * @param xbelFilePath - String containing the path to the

 * file to import.

 * @return SUCCESS or FAILURE depending on whether the 

 * import process was successful.

 ==============================================================*/

int BookmarksManager::importBookmarks(QString xbelFilePath)

{

    XbelReader *reader = new XbelReader(this);

    bool retVal = false;

    if(xbelFilePath.isEmpty() || !QFile::exists(xbelFilePath)) {

        xbelFilePath = "c:\\data\\temp.xml";

        QFile file(xbelFilePath);

        if(file.exists())

            file.remove();

        if (!file.open(QIODevice::WriteOnly | QIODevice::Text))

            return false;

        QTextStream out(&file); 

        out << defaultBookmarksList;

        out.flush();

        file.close();

    } 

    QFile file(xbelFilePath);

    if(file.exists()) {

        file.open(QIODevice::ReadOnly | QIODevice::Text);

        retVal = reader->read(&file);

        file.close();

    }

    if(reader)

        delete reader;

    return retVal ? SUCCESS : FAILURE;

}

/**==============================================================

 * Exports all bookmarks in the database to an XBEL file. This function

 * expects a valid file path to be passed in. If the path is not valid

 * a default file path will be used. If a file with that name already 

 * exists at that location,

 * @param xbelFilePath String containing the path of the file to 

 * export to.

 * @return SUCCESS or FAILURE depending on whether the 

 * export process was successful.

 ==============================================================*/

int BookmarksManager::exportBookmarks(QString xbelFilePath)

{

    XbelWriter *writer = new XbelWriter(this);

    bool retVal = false;

    if(xbelFilePath.isEmpty()) {

        xbelFilePath = "c:\\data\\myBookmarks.xml";

    }  

    QFile file(xbelFilePath);

    if(file.exists()) {

        file.remove(xbelFilePath);

    }

    file.open(QIODevice::WriteOnly | QIODevice::Text);

    retVal = writer->writeFile(&file);

    file.flush();

    file.close();

    if(writer)

        delete writer;

    return retVal ? SUCCESS : FAILURE;

}

/**==============================================================

 * Description: Modify the existing bookmark. Given id of the bookmark

 * and new title or url, it modifies the existing bookmark.

 * Returns : Success(0) or Failure(-1 or -2).

 ================================================================*/

int BookmarksManager::modifyBookmark(int origBookmarkId, QString newTitle, QString newURL)

{

    int retVal = SUCCESS;

    // Client has to at least pass title or url

    if(newTitle.isEmpty() && newURL.isEmpty())

       retVal = FAILURE;

    if(retVal == SUCCESS) {

        if (m_db.isOpen()) { 

              QSqlQuery query(m_db);

            if(newTitle.isEmpty()) {        

                query.prepare("UPDATE bookmarks SET url=:newurl WHERE id=:bmId");

                query.bindValue(":newurl", normalizeUrl(newURL));

                query.bindValue(":bmId", origBookmarkId);

            } else if(newURL.isEmpty()) { 

                query.prepare("UPDATE bookmarks SET title=:newTitle WHERE id=:bmId");

                query.bindValue(":newTitle", newTitle);

                query.bindValue(":bmId", origBookmarkId);

            } else {

                query.prepare("UPDATE bookmarks SET url=:newurl, title=:newTitle WHERE id=:bmId");

                query.bindValue(":newurl", normalizeUrl(newURL));

                query.bindValue(":newTitle", newTitle);

                query.bindValue(":bmId", origBookmarkId);

            }

            if (!query.exec()) {

                lastErrMsg(query);

                return DATABASEERROR;

            } 

            if (query.numRowsAffected() == 0) {

                // No update happened - must be an invalid id

                // TODO: shall we return some other status

                retVal = FAILURE;

            }

        } else 

            retVal = FAILURE;

    }

    return retVal;

}

/**===================================================================================

 * Description: Delete the bookmark item, also delete all the tags associated with it.

 * Returns: SUCCESS(0) or Failure(-1 or -2)

 ======================================================================================*/

int BookmarksManager::deleteBookmark(int bookmarkId)

{

    int retVal = SUCCESS;

    if (m_db.isOpen()) {      

        QSqlQuery query(m_db);

        // TODO: Need to think about whether we need to get sortIndex and update all the 

        // rows after the deletion or not

        // TODO: check if transaction() has been supported 

        // by calling hasfeature() function first

        m_db.transaction();

        query.prepare("DELETE FROM bookmarks WHERE id=:bmId");

        query.bindValue(":bmId", bookmarkId);

        if (!query.exec()) {

            lastErrMsg(query);

            m_db.rollback();

            return DATABASEERROR;

        }

        query.prepare("DELETE FROM tags WHERE bmid=:bmId");

        query.bindValue(":bmId", bookmarkId);

        if (!query.exec()) {

            lastErrMsg(query);

            m_db.rollback();

            return DATABASEERROR;

        } 

        if (!m_db.commit()) {

            qDebug() << m_db.lastError().text();

            m_db.rollback();

            return DATABASEERROR;

        }         

    } else 

        retVal = FAILURE;

    return retVal;     

}

/**===================================================================================

 * Description: Delete all records from the bookmarks table as well as all the tags.

 * Returns: SUCCESS(0) or FAILURE(-1 or -2)

 ======================================================================================*/

int BookmarksManager::clearAll()

{

    int retVal = SUCCESS;

    if (m_db.isOpen()) {        

       QSqlQuery query(m_db);

       // TODO: check if transaction() has been supported 

       // by calling hasfeature() function first

       m_db.transaction();

       if(!query.exec("DELETE FROM bookmarks")) {  

            lastErrMsg(query);

            m_db.rollback();

            retVal = DATABASEERROR;

       } 

       if (retVal == SUCCESS && !query.exec("DELETE FROM tags")) {

            lastErrMsg(query);

            m_db.rollback();

            retVal = DATABASEERROR;

       } 

       if (retVal == SUCCESS && !m_db.commit()) {

           qDebug() << m_db.lastError().text();

           m_db.rollback();

           retVal = DATABASEERROR;

       }

    } else 

        retVal = FAILURE;

    return retVal;     

}

/**==============================================================

 * Description: Deletes a single tag associated with the bookmark

 * Returns: SUCCESS(0) or FAILURE (-1 or -2)

 ===============================================================*/

int BookmarksManager::deleteTag(int bookmarkId, QString tagToDelete)

{

    int retVal = SUCCESS;

    if(tagToDelete.isEmpty()|| bookmarkId < 0)

          retVal = FAILURE;

    if (retVal == SUCCESS) {

        if (m_db.isOpen()) {

            QSqlQuery query(m_db);

            query.prepare("DELETE FROM tags WHERE bmid=:bmId AND tag=:tag");

            query.bindValue(":bmId", bookmarkId);

            query.bindValue(":tag", tagToDelete);

            if (!query.exec()) {

                lastErrMsg(query);

                retVal = DATABASEERROR;

            }

        } else 

            retVal = FAILURE;

    }

    return retVal;     

}

/**================================================================

 * Description: Adds a single tag associated given the bookmark id

 * Returns: SUCCESS(0) or FAILURE (-1 or -2)

 ==================================================================*/

int BookmarksManager::addTag(int bookmarkId, QString tagToAdd)

{

    int retVal = SUCCESS;

    if(tagToAdd.isEmpty()|| bookmarkId < 0)

       retVal = FAILURE;

    if(retVal == SUCCESS) {

        if (m_db.isOpen()) {     

             QSqlQuery query(m_db);

            query.prepare("INSERT INTO tags (bmid, tag) "

                     "VALUES (:id, :tag)");                      

            query.bindValue(":id",   QVariant(bookmarkId));

            query.bindValue(":tag",  QVariant(tagToAdd));

            if (!query.exec()) {

                lastErrMsg(query);

                retVal = DATABASEERROR;

            } 

        } else 

            retVal = FAILURE;

    }

    return retVal;

}

/**==============================================================

 * Description: Finds all the bookmarks weather they have tags 

 * or not.

 * Returns: A pointer to BookmarkResults object or NULL.

 ===============================================================*/

BookmarkResults *BookmarksManager::findAllBookmarks()

{

    BookmarkResults * results = NULL; 

    QString queryStr = QString("SELECT "

                               " id, title, url, sortIndex " 

                               " FROM bookmarks ORDER BY sortIndex");

    if (m_db.isOpen()) {

        QSqlQuery *query = new QSqlQuery(m_db);

        if (query->exec(queryStr)) {

             results = new BookmarkResults(query);

        } else {

            qDebug() << query->lastError().text() << " Query: " << query->lastQuery();

            results = NULL;

        }

    }

    return results;

}

/**==============================================================

 * Description: Finds all the distinct tags.

 * Returns: A pointer to TagResults object or NULL.

 ===============================================================*/

TagResults *BookmarksManager::findAllTags()

{

    TagResults * results = NULL; 

    if (m_db.isOpen()) {

        QSqlQuery *query = new QSqlQuery(m_db);

        if (query->exec("SELECT DISTINCT tag FROM tags")) {

            // TODO: do we need javascript hack here like in findAllBookmarks API.

            results = new TagResults(query); 

        } else {

            qDebug() << query->lastError().text() << " Query: " << query->lastQuery();

            results = NULL;

        }

    }

    return results;

}

/**==============================================================

 * Description: Finds all the bookmarks associated with a given

 * tag. 

 * Returns: A pointer to BookmarkResults object or NULL.

 ===============================================================*/

BookmarkResults *BookmarksManager::findBookmarksByTag(QString tag)

{

    BookmarkResults * results = NULL; 

    QString queryStr = QString("SELECT "

                               " id, title, url, sortIndex " 

                               " FROM bookmarks b JOIN"

                               " tags t ON b.id=t.bmid WHERE" 

                               " t.tag=:tag");

     if (m_db.isOpen()) {

         QSqlQuery *query = new QSqlQuery(m_db);

         query->prepare(queryStr);

         query->bindValue(":tag", tag);

         if (query->exec()) {