#include "GLSelectionRectangle.hpp"
#include "Camera.hpp"
#include "3DScene.hpp"

#include <GL/glew.h>

namespace Slic3r {
namespace GUI {

void GLSelectionRectangle::start_dragging(const Vec2d& mouse_position, float width, float height, EState status)
{
    if (is_dragging() || status == Off)
        return;

    m_width = width;
    m_height = height;
    m_status = status;
    m_start_corner = mouse_position;
    m_end_corner = mouse_position;
}



void GLSelectionRectangle::dragging(const Vec2d& mouse_position)
{
    if (is_dragging())
        m_end_corner = mouse_position;
}



std::vector<unsigned int> GLSelectionRectangle::end_dragging(const Camera& camera, const std::vector<Vec3d>& points)
{
    if (!is_dragging())
        return std::vector<unsigned int>();

    m_status = Off;
    std::vector<unsigned int> out;

    const std::array<int, 4>& viewport = camera.get_viewport();
    const Transform3d& modelview_matrix = camera.get_view_matrix();
    const Transform3d& projection_matrix = camera.get_projection_matrix();

    // bounding box created from the rectangle corners - will take care of order of the corners
    BoundingBox rectangle(Points{Point(m_start_corner.cast<int>()), Point(m_end_corner.cast<int>())});

    // Iterate over all points and determine whether they're in the rectangle.
    for (unsigned int i=0; i<points.size(); ++i) {
        const Vec3d& point = points[i];
        GLdouble out_x, out_y, out_z;
        ::gluProject((GLdouble)point(0), (GLdouble)point(1), (GLdouble)point(2), (GLdouble*)modelview_matrix.data(), (GLdouble*)projection_matrix.data(), (GLint*)viewport.data(), &out_x, &out_y, &out_z);
        out_y = m_height - out_y;

        if (rectangle.contains(Point(out_x, out_y)))
            out.push_back(i);
    }

    return out;
}



void GLSelectionRectangle::render() const
{
    float render_color[3];

    switch (m_status) {
        case Off : return;
        case SlaSelect : render_color[0] = 0.f;
                         render_color[1] = 1.f;
                         render_color[2] = 0.f;
                         break;
        case SlaDeselect : render_color[0] = 1.f;
                           render_color[1] = 0.3f;
                           render_color[2] = 0.3f;
                           break;
    }

    glsafe(::glColor3fv(render_color));
    glsafe(::glLineWidth(1.5f));

    glsafe(::glPushAttrib(GL_TRANSFORM_BIT));   // remember current MatrixMode

    glsafe(::glMatrixMode(GL_MODELVIEW));       // cache modelview matrix and set to identity
    glsafe(::glPushMatrix());
    glsafe(::glLoadIdentity());

    glsafe(::glMatrixMode(GL_PROJECTION));      // cache projection matrix and set to identity
    glsafe(::glPushMatrix());
    glsafe(::glLoadIdentity());

    glsafe(::glOrtho(0.f, m_width, m_height, 0.f, -1.f, 1.f)); // set projection matrix so that world coords = window coords

    // render the selection  rectangle (window coordinates):
    glsafe(::glPushAttrib(GL_ENABLE_BIT));
    glsafe(::glLineStipple(4, 0xAAAA));
    glsafe(::glEnable(GL_LINE_STIPPLE));

    ::glBegin(GL_LINE_LOOP);
    ::glVertex3f((GLfloat)m_start_corner(0), (GLfloat)m_start_corner(1), (GLfloat)0.5f);
    ::glVertex3f((GLfloat)m_end_corner(0), (GLfloat)m_start_corner(1), (GLfloat)0.5f);
    ::glVertex3f((GLfloat)m_end_corner(0), (GLfloat)m_end_corner(1), (GLfloat)0.5f);
    ::glVertex3f((GLfloat)m_start_corner(0), (GLfloat)m_end_corner(1), (GLfloat)0.5f);
    glsafe(::glEnd());
    glsafe(::glPopAttrib());

    glsafe(::glPopMatrix());                // restore former projection matrix
    glsafe(::glMatrixMode(GL_MODELVIEW));
    glsafe(::glPopMatrix());                // restore former modelview matrix
    glsafe(::glPopAttrib());                // restore former MatrixMode
    
}


} // namespace GUI
} // namespace Slic3r