/*
  This program is free software; you can redistribute it and/or
  modify it under the terms of the GNU General Public License
  as published by the Free Software Foundation; either version
  2 of the License, or (at your option) any later version.
*/

#include <QSqlQuery>
#include <QFont>
#include <QFile>
#include <QLocale>

#include <algorithm>
#include <random>
#include <chrono>

#include "picfilesmodel.h"
#include "smglobals.h"
#include "smtreeitem.h"
#include "helper.h"


PicFilesModel::PicFilesModel(const QStringList &headers, QObject *parent) : SmTreeModel(headers, parent) {
    //conjure up model
    mMappingTreeModel = static_cast<MappingTreeModel*>(SmGlobals::instance()->model("MappingTree"));

    //setup database
    mDb = QSqlDatabase::database("treedb");
    mPopulateQS = QString("SELECT DISTINCT(pics.ipicsid), pics.tfilename, pics.isize, pics.tformat, pics.dtadded, pics.cmd5sum, pics.cpicsize FROM pics, pics_mappings WHERE pics_mappings.imappings_parents_id IN (%1) AND pics_mappings.ipics_id = pics.ipicsid ORDER BY pics.tfilename");
    mMappingsQS = QString("SELECT DISTINCT(pics_mappings.imappings_parents_id) FROM pics_mappings WHERE pics_mappings.ipics_id IN (%1)");
}

void PicFilesModel::setMapping(int pMapId){
    QList<QVariant> ids = mMappingTreeModel->childList(pMapId, MappingTreeModel::MappingId);
    mMappingIds.clear();
    foreach(QVariant i, ids){
        mMappingIds << i.toInt();
    }
}

QVariant PicFilesModel::data(const QModelIndex &index, int role) const {
    if(role == Qt::FontRole){
        if(index.column() == Md5Sum){
            return QFont("Monospace");
        }
    }
    if(role == Qt::ForegroundRole){
        if(index.column() == Size){
            int fileSize = index.data(SizeRole).toInt();
            if(fileSize > 1024 * 1024 * 1024){
                return QColor(Qt::red);
            }else{
                return QColor(Qt::green);
            }
        }
    }
    SmTreeItem *item = itemAt(index);
    if(role == FileNameRole){
        return item->data(FileName);
    }
    if(role == SizeRole){
        return item->data(Size);
    }
    if(role == MimeTypeRole){
        return item->data(MimeType);
    }
    if(role == FullPathRole){
        return item->data(FullPath);
    }
    if(role == IdRole){
        return item->data(Id);
    }
    if(role == AddedRole){
        return item->data(Added);
    }
    if(role == Md5SumRole){
        return item->data(Md5Sum);
    }
    if(role == PicSizeRole){
        return item->data(PicSize);
    }
    return SmTreeModel::data(index, role);
}

QList<QVariant> PicFilesModel::dataList(const QModelIndex &idx){
    QList<QVariant> retval;
    if(!idx.isValid()){
        return retval;
    }
    SmTreeItem *item = itemAt(idx);
    for(int i = 0; i < NumFields; ++i){
        retval << item->data(i);
    }
    QList<MappingData> mapData = mappingDataFromFile(idx.data(PicFilesModel::IdRole).toInt());
    QList<QStringList> mappings;
    foreach(MappingData d, mapData){
        mappings << d.path;
    }

    retval.append(QVariant::fromValue(mappings));
    return retval;
}

QList<QList<QVariant> > PicFilesModel::allFiles() const {
    QList<QList<QVariant> >  retval;
    //assume depth of exactly 1
    SmTreeItem *rootItem = root();
    for(int i = 0; i < rootItem->childCount(); ++i){
        SmTreeItem *cur = rootItem->child(i);
        QList<QVariant> data;
        for(int j = 0; j < cur->columnCount(); ++j){
            data << cur->data(j);
        }
        retval << data;
    }
    return retval;
}

void PicFilesModel::removeFiles(const QList<QPair<int, QString> > &files){
    QSqlQuery deleteFile(mDb);
    deleteFile.prepare("DELETE FROM pics WHERE ipicsid = :id");
    QList<int> success;
    // remove from model
    for(int i = 0; i < files.size(); ++i){
        QPair<int, QString> cur = files.at(i);
        deleteFile.bindValue(":id", cur.first);
        if(deleteFile.exec()){
            success << cur.first;
            QFile::remove(cur.second);
        }
    }
    // remove from view
    foreach(int id, success){
        QModelIndex idx = find(id, Id);
        if(idx.isValid()){
            removeRows(idx.row(), 1, QModelIndex());
        }
    }
}

bool PicFilesModel::changeMappings(const QList<int> &fileIds, const QList<QVariant> &parentIds){
    mDb.transaction();
    QSqlQuery deleteMappingsQ(mDb);
    deleteMappingsQ.prepare("DELETE FROM pics_mappings WHERE ipics_id = :id");
    QSqlQuery addMappingsQ(mDb);
    addMappingsQ.prepare("INSERT INTO pics_mappings(ipics_id, imappings_parents_id) VALUES(:pid, :id)");
    foreach(int fid, fileIds){
        deleteMappingsQ.bindValue(":id", fid);
        if(!deleteMappingsQ.exec()){
            goto error;
        }
        foreach(QVariant pid, parentIds){
            addMappingsQ.bindValue(":pid", fid);
            addMappingsQ.bindValue(":id", pid);
            if(!addMappingsQ.exec()){
                goto error;
            }
        }
    }
    mDb.commit();
    return true;

    error:
    mDb.rollback();
    return false;
}

SmTreeItem *PicFilesModel::mappingTreeFromFile(int fileId){
    QList<int> fileIds = QList<int>() << fileId;
    QList<int> parentIds = mappingPIdsFromFiles(fileIds);
    if(parentIds.isEmpty()){
        return 0;
    }
    SmTreeItem *retval = new SmTreeItem(2);
    QSqlQuery mpq(mDb);
    mpq.prepare("SELECT imapping_parents_id, iparent_id, tdescription_name, mapping_parents.idescription_id FROM mapping_parents, mapping_description WHERE imapping_parents_id = :id AND mapping_parents.idescription_id = mapping_description.idescription_id");
    foreach(int pId, parentIds){
        QList<QVariantList> curData;
        int curParent = -1;
        mpq.bindValue(":id", pId);
        mpq.exec();
        while(mpq.next()){
            QVariantList d;
            d << mpq.value(2) << mpq.value(0);
            curData << d;
            curParent = mpq.value(1).toInt();
        }
        while(curParent != -1){
            mpq.bindValue(":id", curParent);
            mpq.exec();
            while(mpq.next()){
                QVariantList d;
                d << mpq.value(2) << mpq.value(0);
                curData << d;
                curParent = mpq.value(1).toInt();
            }
        }
        std::reverse(curData.begin(), curData.end());
        SmTreeItem *parentItem = retval;
        for(int i = 0; i < curData.size(); ++i){
            QVariantList data = curData.at(i);
            SmTreeItem *searchItem = findRecursive(parentItem, data.at(0), data.at(1));
            if(searchItem){
                parentItem = searchItem;
            }else{
                int where;
                for(where = 0; where < parentItem->childCount(); ++where){
                    SmTreeItem *c = parentItem->child(where);
                    if(c->data(0).toString() > data.at(0).toString()){
                        break;
                    }
                }
                SmTreeItem *newChild = new SmTreeItem(data, parentItem);
                parentItem->insertChild(where, newChild);
                parentItem = newChild;
            }
        }
    }
    return retval;
}

SmTreeItem *PicFilesModel::findRecursive(SmTreeItem *start, const QVariant &name, const QVariant id) const{
    if(!start){
        return 0;
    }
    if(start->data(0) == name && start->data(1) == id){
        return start;
    }
    for(int i = 0; i < start->childCount(); ++i){
        SmTreeItem *child = start->child(i);
        if(child->data(0) == name && child->data(1) == id){
            return child;
        }
        if(child->childCount()){
            return findRecursive(child, name, id);
        }
    }
    SmTreeItem *next = start->next();
    if(next){
        return findRecursive(next, name, id);
    }
    return 0;
}

QList<MappingData> PicFilesModel::mappingDataFromFile(int fileId){
    QList<int> d = QList<int>() << fileId;
    return mappingDataFromFiles(d);
}

QList<MappingData> PicFilesModel::mappingDataFromFiles(const QList<int> fileIds){
    QList<int> parentIds = mappingPIdsFromFiles(fileIds);
    if(parentIds.isEmpty()){
        return QList<MappingData>();
    }
    QList<MappingData> retval;
    QSqlQuery mpq(mDb);
    mpq.prepare("SELECT imapping_parents_id, iparent_id, tdescription_name, mapping_parents.idescription_id FROM mapping_parents, mapping_description WHERE imapping_parents_id = :id AND mapping_parents.idescription_id = mapping_description.idescription_id");
    foreach(int pId, parentIds){
        MappingData curData;
        int curParent = -1;
        mpq.bindValue(":id", pId);
        mpq.exec();
        while(mpq.next()){
            curData.name = mpq.value(2).toString();
            curData.mappingId = pId;
            curData.descId = mpq.value(3).toInt();
            curData.parents << pId;
            curData.path << curData.name;
            curParent = mpq.value(1).toInt();
        }
        while(curParent != -1){
            mpq.bindValue(":id", curParent);
            mpq.exec();
            while(mpq.next()){
                curData.parents << curParent;
                curData.path << mpq.value(2).toString();
                curParent = mpq.value(1).toInt();
            }
        }
        std::reverse(curData.parents.begin(), curData.parents.end());
        std::reverse(curData.path.begin(), curData.path.end());
        retval << curData;
    }
    return retval;
}

QList<int> PicFilesModel::mappingPIdsFromFiles(QList<int> fileIds){
    if(fileIds.isEmpty()){
        return QList<int>();
    }
    QStringList idList;
    foreach(int id, fileIds){
        idList << QString::number(id);
    }
    QString qTempl = QString(mMappingsQS.arg(idList.join(",")));
    QSqlQuery q(mDb);
    q.prepare(qTempl);
    if(!q.exec()){
        mDb.close();
        mDb.open();
        return QList<int>();
    }
    QList<int> retval;
    while(q.next()){
        retval << q.value(0).toInt();
    }
    return retval;
}

void PicFilesModel::selectFromAll(){
    mAllPics.clear();
    QSqlQuery q("SELECT tfilename, cmd5sum, ipicsid FROM pics", mDb);
    while(q.next()){
        QList<QVariant> cur;
        cur << q.value(0) << q.value(1) << q.value(2);
        mAllPics << cur;
    }
    mCurrentPics = &mAllPics;
}

void PicFilesModel::selectFromRecent(int days){
    mAllPics.clear();
    QString qTempl = QString("SELECT tfilename, cmd5sum, ipicsid FROM pics WHERE dtadded > now() - interval '%1 days'").arg(QString::number(days));
    QSqlQuery q(qTempl, mDb);
    while(q.next()){
        QList<QVariant> cur;
        cur << q.value(0) << q.value(1) << q.value(2);
        mAllPics << cur;
    }
    mCurrentPics = &mAllPics;
}

void PicFilesModel::selectFromSelection(QList<QVariant> ids){
    mAllPics.clear();
    QStringList idQS;
    foreach (QVariant i, ids){
        idQS << QString::number(i.toInt());
    }
    QString inPart = idQS.join(',');
    QString qTempl = QString("SELECT tfilename, cmd5sum, ipicsid FROM pics, pics_mappings WHERE pics_mappings.imappings_parents_id IN (%1) AND pics_mappings.ipics_id = pics.ipicsid").arg(inPart);
    QSqlQuery q(qTempl, mDb);
    while(q.next()){
        QList<QVariant> cur;
        cur << q.value(0) << q.value(1) << q.value(2);
        mAllPics << cur;
    }
    mCurrentPics = &mAllPics;
}

// delete this func once the one above works
void PicFilesModel::allPicIds(){
    mAllPics.clear();
    mCurrentBatch = 0;
    QSqlQuery q("SELECT tfilename, cmd5sum, ipicsid FROM pics", mDb);
    while(q.next()){
        QList<QVariant> cur;
        cur << q.value(0) << q.value(1) << q.value(2);
        mAllPics << cur;
    }
    unsigned seed = std::chrono::system_clock::now().time_since_epoch().count();
    std::shuffle(mAllPics.begin(), mAllPics.end(), std::default_random_engine(seed));
    mCurrentPics = &mAllPics;
}

void PicFilesModel::recentPicIds(){
    mRecentPics.clear();
    mCurrentBatch = 0;
    QSqlQuery q("SELECT tfilename, cmd5sum, ipicsid FROM pics WHERE dtadded > now() - interval '6 months'", mDb);
    while(q.next()){
        QList<QVariant> cur;
        cur << q.value(0) << q.value(1) << q.value(2);
        mRecentPics << cur;
    }
    unsigned seed = std::chrono::system_clock::now().time_since_epoch().count();
    std::shuffle(mRecentPics.begin(), mRecentPics.end(), std::default_random_engine(seed));
    mCurrentPics = &mRecentPics;
}

QList<QList<QVariant> > PicFilesModel::getNextBatch(){
    if(mCurrentBatch * 100 >= mAllPics.count()){
        mCurrentBatch = 0;
    }
    int start = mCurrentBatch * 100;
    QList<QList<QVariant> > res = mCurrentPics->mid(start, 100);
    QList<QList<QVariant> > retval;
    for(QList<QList<QVariant> >::const_iterator it = res.constBegin(); it != res.constEnd(); ++it){
        QList<QVariant> c = *it;
        QList<QVariant> item;
        item << Helper::createArchivePath(c.value(0).toString(), c.value(1).toString()) << c.value(2);
        retval << item;
    }
    ++mCurrentBatch;
    return retval;
}

void PicFilesModel::populate(){
    SmTreeItem *root = new SmTreeItem(NumFields);
    QStringList idList;
    foreach(int id, mMappingIds){
        idList << QString::number(id);
    }
    QString query = mPopulateQS.arg(idList.join(","));
    QSqlQuery q(query, mDb);
    while(q.next()){
        QList<QVariant> data;
        data << q.value(1) << q.value(2) << q.value(3); // Filename, size and Mime type
        data << Helper::createArchivePath(q.value(1).toString(), q.value(5).toString()); // full path;
        data << q.value(0) << q.value(4) << q.value(5); //Id, added and md5
        data << q.value(6); // picsize
        SmTreeItem *child = new SmTreeItem(data, root);
        root->appendChild(child);
    }
    setRoot(root);
}