/*
 *  This file is part of RawTherapee.
 *
 *  Copyright (c) 2004-2010 Gabor Horvath <hgabor@rawtherapee.com>
 *
 *  RawTherapee 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 3 of the License, or
 *  (at your option) any later version.
 *
 *  RawTherapee 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with RawTherapee.  If not, see <https://www.gnu.org/licenses/>.
 */
#include "inspector.h"
#include "guiutils.h"
#include <gtkmm.h>
#include "cursormanager.h"
#include "guiutils.h"
#include "options.h"
#include "pathutils.h"
#include "rtscalable.h"
#include "../rtengine/previewimage.h"
#include "../rtengine/rt_math.h"

InspectorBuffer::InspectorBuffer(const Glib::ustring &imagePath) : currTransform(0), fromRaw(false)
{
    if (!imagePath.empty() && Glib::file_test(imagePath, Glib::FILE_TEST_EXISTS) && !Glib::file_test(imagePath, Glib::FILE_TEST_IS_DIR)) {
        imgPath = imagePath;

        // generate thumbnail image
        Glib::ustring ext = getExtension (imagePath);

        if (ext.empty()) {
            imgPath.clear();
            return;
        }

        rtengine::PreviewImage pi(imagePath, ext, rtengine::PreviewImage::PIM_EmbeddedOrRaw);
        Cairo::RefPtr<Cairo::ImageSurface> imageSurface = pi.getImage();

        if (imageSurface) {
            imgBuffer.setSurface(imageSurface);
            fromRaw = true;
        } else {
            imgPath.clear();
        }
    }
}

/*
InspectorBuffer::~InspectorBuffer() {
}
*/

//int InspectorBuffer::infoFromImage (const Glib::ustring& fname)
//{
//
//    rtengine::FramesMetaData* idata = rtengine::FramesMetaData::fromFile (fname, nullptr, true);
//
//    if (!idata) {
//        return 0;
//    }
//
//    int deg = 0;
//
//    if (idata->hasExif()) {
//        if      (idata->getOrientation() == "Rotate 90 CW" ) {
//            deg = 90;
//        } else if (idata->getOrientation() == "Rotate 180"   ) {
//            deg = 180;
//        } else if (idata->getOrientation() == "Rotate 270 CW") {
//            deg = 270;
//        }
//    }
//
//    delete idata;
//    return deg;
//}

Inspector::Inspector () : currImage(nullptr), scaled(false), active(false)
{
    set_name("Inspector");
    window.set_visible(false);
    window.add_events(Gdk::KEY_PRESS_MASK);
    window.signal_key_release_event().connect(sigc::mem_fun(*this, &Inspector::on_key_release));
    window.set_title("RawTherapee Inspector");
    window.add(*this);
    window.show_all();
    window.set_visible(false);
    active = true; // always track inspected thumbnails
}

Inspector::~Inspector()
{
    deleteBuffers();
}

void Inspector::showWindow(bool scaled)
{
    this->scaled = scaled;
    window.fullscreen();
    window.set_visible(true);
}

bool Inspector::on_key_release(GdkEventKey *event)
{
    window.set_visible(false);
    return true;
}

bool Inspector::on_draw(const ::Cairo::RefPtr< Cairo::Context> &cr)
{

    Glib::RefPtr<Gdk::Window> win = get_window();

    if (!win) {
        return false;
    }

    if (!active) {
        active = true;
    }


    // cleanup the region


    if (currImage && currImage->imgBuffer.surfaceCreated()) {
        // this will eventually create/update the off-screen pixmap

        // compute the displayed area
        rtengine::Coord availableSize;
        rtengine::Coord topLeft;
        rtengine::Coord dest(0, 0);
        int deviceScale = get_scale_factor();
        availableSize.x = win->get_width() * deviceScale;
        availableSize.y = win->get_height() * deviceScale;
        int imW = currImage->imgBuffer.getWidth();
        int imH = currImage->imgBuffer.getHeight();
        double scale = 1.0;
        if (scaled) {
            // reduce size of image to fit into window
            scale = rtengine::min<double>(1.0, rtengine::min<double>((double)availableSize.x/imW, (double)availableSize.y/imH));
            availableSize.x /= scale;
            availableSize.y /= scale;
        }

        if (imW < availableSize.x) {
            // center the image in the available space along X
            topLeft.x = 0;
            dest.x = (availableSize.x - imW) / 2;
        } else {
            // partial image display
            // double clamp
            topLeft.x = center.x + availableSize.x / 2;
            topLeft.x = rtengine::min<int>(topLeft.x, imW);
            topLeft.x -= availableSize.x;
            topLeft.x = rtengine::max<int>(topLeft.x, 0);
        }

        if (imH < availableSize.y) {
            // center the image in the available space along Y
            topLeft.y = 0;
            dest.y = (availableSize.y - imH) / 2;
        } else {
            // partial image display
            // double clamp
            topLeft.y = center.y + availableSize.y / 2;
            topLeft.y = rtengine::min<int>(topLeft.y, imH);
            topLeft.y -= availableSize.y;
            topLeft.y = rtengine::max<int>(topLeft.y, 0);
        }

        //printf("center: %d, %d   (img: %d, %d)  (availableSize: %d, %d)  (topLeft: %d, %d)\n", center.x, center.y, imW, imH, availableSize.x, availableSize.y, topLeft.x, topLeft.y);

        // define the destination area
        currImage->imgBuffer.setDrawRectangle(win, dest.x, dest.y, rtengine::min<int>(availableSize.x - dest.x, imW), rtengine::min<int>(availableSize.y - dest.y, imH), false);
        currImage->imgBuffer.setSrcOffset(topLeft.x, topLeft.y);

        if (!currImage->imgBuffer.surfaceCreated()) {
            return false;
        }

        // Draw!

        Gdk::RGBA c;
        Glib::RefPtr<Gtk::StyleContext> style = get_style_context();

        // draw the background
        //style->render_background(cr, 0, 0, get_width(), get_height());

        ///* --- old method (the new method does not seem to work)
        c = style->get_background_color (Gtk::STATE_FLAG_NORMAL);
        cr->set_source_rgb (c.get_red(), c.get_green(), c.get_blue());
        cr->set_line_width (0);
        cr->rectangle (0, 0, availableSize.x, availableSize.y);
        cr->fill ();
        //*/

        bool scaledImage = scaled && (imW > win->get_width() || imH > win->get_height());
	if (deviceScale == 1 && !scaledImage) {
            // standard drawing
            currImage->imgBuffer.copySurface(win);
	}
	else {
            // consider device scale and image scale
            if (deviceScale > 1) {
                // use full device resolution and let it scale the image (macOS)
                cairo_surface_set_device_scale(cr->get_target()->cobj(), scale, scale);
                scaledImage = false;
            }
            Glib::RefPtr<Gdk::Pixbuf> crop = Gdk::Pixbuf::create(currImage->imgBuffer.getSurface(), topLeft.x, topLeft.y, rtengine::min<int>(imW, availableSize.x), rtengine::min<int>(imH, availableSize.y));
            if (!scaledImage) {
                Gdk::Cairo::set_source_pixbuf(cr, crop, dest.x, dest.y);
            }
            else {
                // assume that the device does not support scaling (Linux)
                crop = crop->scale_simple(imW*scale, imH*scale, Gdk::INTERP_BILINEAR);
                Gdk::Cairo::set_source_pixbuf(cr, crop, dest.x*scale, dest.y*scale);
            }
            cr->paint();
	}

        /* --- not for separate window
        // draw the frame
        c = style->get_border_color (Gtk::STATE_FLAG_NORMAL);
        cr->set_source_rgb (c.get_red(), c.get_green(), c.get_blue());
        cr->set_line_width (1);
        cr->rectangle (0.5, 0.5, availableSize.x - 1, availableSize.y - 1);
        cr->stroke ();
        */
    }

    return true;
}

void Inspector::mouseMove (rtengine::Coord2D pos, int transform)
{
    if (!active) {
        return;
    }

    if (currImage) {
        center.set(int(rtengine::LIM01(pos.x)*double(currImage->imgBuffer.getWidth())), int(rtengine::LIM01(pos.y)*double(currImage->imgBuffer.getHeight())));
    } else {
        center.set(0, 0);
    }

    queue_draw();
}

void Inspector::switchImage (const Glib::ustring &fullPath)
{
    if (!active) {
        return;
    }

    if (delayconn.connected()) {
        delayconn.disconnect();
    }

    next_image_path = fullPath;
    if (!options.inspectorDelay) {
        doSwitchImage();
    } else {
        delayconn = Glib::signal_timeout().connect(sigc::mem_fun(*this, &Inspector::doSwitchImage), options.inspectorDelay);
    }
}


bool Inspector::doSwitchImage()
{
    Glib::ustring fullPath = next_image_path;
    
    // we first check the size of the list, it may have been changed in Preference
    if (images.size() > size_t(options.maxInspectorBuffers)) {
        // deleting the last entries
        for (size_t i = images.size() - 1; i > size_t(options.maxInspectorBuffers - 1); --i) {
            delete images.at(i);
            images.at(i) = nullptr;
        }

        // resizing down
        images.resize(options.maxInspectorBuffers);
    }

    if (fullPath.empty()) {
        currImage = nullptr;
        queue_draw();
    } else {
        bool found = false;

        for (size_t i = 0; i < images.size(); ++i) {
            if (images.at(i) != nullptr && images.at(i)->imgPath == fullPath) {
                currImage = images.at(i);

                // rolling the list 1 step to the beginning
                for (size_t j = i; j < images.size() - 1; ++j) {
                    images.at(j) = images.at(j + 1);
                }

                images.at(images.size() - 1) = currImage; // move the last used image to the tail
                found = true;
                break;
            }
        }

        if (!found) {
            if (images.size() == size_t(options.maxInspectorBuffers)) {
                // The list is full, delete the first entry
                delete images.at(0);
                images.erase(images.begin());
            }

            // Loading a new image
            InspectorBuffer *iBuffer = new InspectorBuffer(fullPath);

            // and add it to the tail
            if (!iBuffer->imgPath.empty()) {
                images.push_back(iBuffer);
                currImage = images.at(images.size() - 1);
            } else {
                delete iBuffer;
                currImage = nullptr;
            }
        }
    }

    return true;
}

void Inspector::deleteBuffers ()
{
    for (size_t i = 0; i < images.size(); ++i) {
        if (images.at(i) != nullptr) {
            delete images.at(i);
            images.at(i) = nullptr;
        }
    }

    images.resize(0);
    currImage = nullptr;
}

void Inspector::flushBuffers ()
{
    if (!active) {
        return;
    }

    deleteBuffers();
}

void Inspector::setActive(bool state)
{
    if (!state) {
        flushBuffers();
    }

    //active = state;
}


Gtk::SizeRequestMode Inspector::get_request_mode_vfunc () const
{
    return Gtk::SIZE_REQUEST_CONSTANT_SIZE;
}

void Inspector::get_preferred_height_vfunc (int &minimum_height, int &natural_height) const
{
    minimum_height= 50 * RTScalable::getScale();
    natural_height = 300 * RTScalable::getScale();
}

void Inspector::get_preferred_width_vfunc (int &minimum_width, int &natural_width) const
{
    minimum_width = 50 * RTScalable::getScale();
    natural_width = 200 * RTScalable::getScale();
}

void Inspector::get_preferred_height_for_width_vfunc (int width, int &minimum_height, int &natural_height) const
{
    get_preferred_height_vfunc(minimum_height, natural_height);
}

void Inspector::get_preferred_width_for_height_vfunc (int height, int &minimum_width, int &natural_width) const
{
    get_preferred_width_vfunc (minimum_width, natural_width);
}