/*
  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 <QDateTime>
#include <QDir>
#include <QImage>

#include <sys/inotify.h>
#include <unistd.h>

#include "smdirmodel.h"
#include "smdirwatcher.h"
#include "smtreeitem.h"
#include "helper.h"

SmDirWatcher::SmDirWatcher(int numFields, QObject *parent) : QThread(parent), mFd(0), mDescr(0), mNumFields(numFields) {
    mBufLen = 1024 * (sizeof(struct inotify_event) + 16);
    mINdata = new char[mBufLen];
    mFd = inotify_init();
    mAsyncPool = new QThreadPool(this);
}

void SmDirWatcher::setDir(const QString &dir){
    if(mDescr){
        inotify_rm_watch(mFd, mDescr); //generates IN_IGNORE ???
    }
    foreach(AsyncTask *s, mAsyncTasks){
        s->skipMe();
    }
    mAsyncPool->waitForDone();
    foreach(AsyncTask *s, mAsyncTasks){
        s->deleteLater();
    }
    mAsyncTasks.clear();
    mCurrent = dir;
    QDir d(mCurrent);
    SmTreeItem *rootItem = new SmTreeItem(mNumFields);
    foreach(QFileInfo fi, d.entryInfoList()){
        if(fi.fileName() == "." || fi.fileName() == ".."){
            continue;
        }
        QList<QVariant> data = generalData(fi.absoluteFilePath());
        QString mime = data.at(SmDirModel::Type).toString();
        SmTreeItem *newItem = new SmTreeItem(data, rootItem);
        rootItem->appendChild(newItem);
        Md5Summer *s = new Md5Summer(fi.absoluteFilePath());
        s->setAutoDelete(false);
        connect(s, SIGNAL(md5sumDone(QString,QString)), this, SIGNAL(setMd5Sum(QString,QString)));
        mAsyncTasks.append(s);
        if(mime.startsWith("video")){
            FfmpegGatherer *g = new FfmpegGatherer(fi.absoluteFilePath());
            g->setAutoDelete(false);
            connect(g, SIGNAL(ffmpegDone(QString,QVariantMap)), this, SIGNAL(setFfmpeg(QString,QVariantMap)));
            mAsyncTasks.append(g);
        }else if(mime.startsWith("image")){
            PicSizeGatherer *pg = new PicSizeGatherer(fi.absoluteFilePath());
            pg->setAutoDelete(false);
            connect(pg, SIGNAL(picSizeDone(QString,QVariant)), this, SIGNAL(setPicSize(QString,QVariant)));
            mAsyncTasks.append(pg);
        }
    }
    emit population(rootItem);
    /* mask rationale:
     * IN_DELETE_SELF cannot happen since we're only
     * watching one directory at all time.
     * We don't care about the other events
     */
    mDescr = inotify_add_watch(mFd, qPrintable(dir), IN_CLOSE_WRITE | IN_CREATE | IN_DELETE | IN_MODIFY | IN_MOVED_FROM | IN_MOVED_TO);
}

void SmDirWatcher::startAsyncJobs(){
    foreach(AsyncTask *s, mAsyncTasks){
        mAsyncPool->start(s);
    }
}

void SmDirWatcher::gatherAsync(const QString &path){
    QString mimeType = Helper::mimeType(path);
    Md5Summer *s = new Md5Summer(path);
    connect(s, SIGNAL(md5sumDone(QString,QString)), this, SIGNAL(setMd5Sum(QString,QString)));
    mAsyncPool->start(s);
    if(mimeType.startsWith("video")){
        FfmpegGatherer *g = new FfmpegGatherer(path);
        connect(g, SIGNAL(ffmpegDone(QString,QVariantMap)), this, SIGNAL(setFfmpeg(QString,QVariantMap)));
        mAsyncPool->start(g);
    }else if(mimeType.startsWith("image")){
        PicSizeGatherer *ps = new PicSizeGatherer(path);
        connect(ps, SIGNAL(picSizeDone(QString,QVariant)), this, SIGNAL(setPicSize(QString,QVariant)));
        mAsyncPool->start(ps);
    }
}

QList<QVariant> SmDirWatcher::generalData(const QString &path){
    QFileInfo fi(path);
    QList<QVariant> data;
    data << fi.fileName() << fi.size();
    QString mime = Helper::mimeType(fi.absoluteFilePath());
    data << mime;
    data << fi.lastModified();
    data << QVariant() << QVariant() << QVariant();
    data << fi.absoluteFilePath() << 0;
    return data;
}

void SmDirWatcher::run(){
    int r = read(mFd, mINdata, mBufLen);
    if(r <= 0){
        return;
    }
    int i = 0;
    while(i < r){
        inotify_event *e = reinterpret_cast<inotify_event*>(&mINdata[i]);
        if((!e->len) || (e->mask & IN_IGNORED)){
            i += sizeof(inotify_event) + e->len;
            continue;
        }
        quint32 mask = e->mask;
        QString name = QString("%1/%2").arg(mCurrent).arg(e->name);
        QList<QVariant> d = generalData(name);
        if(mask & IN_CREATE || mask & IN_MOVED_TO){
            emit newData(d, Added);
        }else if(mask & IN_DELETE || mask & IN_MOVED_FROM){
            emit newData(d, Deleted);
        }else if(mask & IN_MODIFY){
            emit newData(d, Modified);
        }else if(mask & IN_CLOSE_WRITE){
            emit newData(d, CloseWrite);
        }
        i += sizeof(inotify_event) + e->len;
    }
}

void SmDirWatcher::stop(){
    quit();
}

AsyncTask::AsyncTask(const QString &path) : mSkip(false), mPath(path) {}

bool AsyncTask::skipMe(){
    if(mStatusMx.tryLock()){
        mSkip = true;
        mStatusMx.unlock();
        return true;
    }
    return false;
}

#include <QDebug>

Md5Summer::Md5Summer(const QString &path) : AsyncTask(path) {}

void Md5Summer::run(){
    mStatusMx.lock();
    bool skip = mSkip;
    mStatusMx.unlock();
    if(skip){
        return;
    }
    QString md5 = Helper::md5Sum(mPath);
    emit md5sumDone(mPath, md5);
}

FfmpegGatherer::FfmpegGatherer(const QString &path) : AsyncTask(path) {}

void FfmpegGatherer::run(){
    mStatusMx.lock();
    bool skip = mSkip;
    mStatusMx.unlock();
    if(skip){
        return;
    }
    QVariantMap retval = Helper::ffmpegData(mPath);
    emit ffmpegDone(mPath, retval);
}

PicSizeGatherer::PicSizeGatherer(const QString &path) : AsyncTask(path) {}

void PicSizeGatherer::run(){
    mStatusMx.lock();
    bool skip = mSkip;
    mStatusMx.unlock();
    if(skip){
        return;
    }
    QVariant retval = Helper::picSize(mPath);
    emit picSizeDone(mPath, retval);
}