#include <stdarg.h>

#include "solvespace.h"

#define mView (&GraphicsWindow::MenuView)
#define mEdit (&GraphicsWindow::MenuEdit)
const GraphicsWindow::MenuEntry GraphicsWindow::menu[] = {
{ 0, "&File",                           0,                              NULL  },
{ 1, "&New\tCtrl+N",                    0,                              NULL  },
{ 1, "&Open...\tCtrl+O",                0,                              NULL  },
{ 1, "&Save\tCtrl+S",                   0,                              NULL  },
{ 1, "Save &As...",                     0,                              NULL  },
{ 1,  NULL,                             0,                              NULL  },
{ 1, "E&xit",                           0,                              NULL  },

{ 0, "&Edit",                           0,                              NULL  },
{ 1, "&Undo\tCtrl+Z",                   0,                              NULL  },
{ 1, "&Redo\tCtrl+Y",                   0,                              NULL  },
{ 1,  NULL,                             0,                              NULL  },
{ 1, "&Unselect All\tEsc",              MNU_UNSELECT_ALL,       27,     mEdit },

{ 0, "&View",                           0,                              NULL  },
{ 1, "Zoom &In\t+",                     MNU_ZOOM_IN,            '+',    mView },
{ 1, "Zoom &Out\t-",                    MNU_ZOOM_OUT,           '-',    mView },
{ 1, "Zoom To &Fit\tF",                 MNU_ZOOM_TO_FIT,        'F',    mView },
{ 1,  NULL,                             0,                              NULL  },
{ 1, "Onto Plane/Csys\tO",              MNU_ORIENT_ONTO,        'O',    mView },
{ 1,  NULL,                             0,                              NULL  },
{ 1, "Dimensions in &Inches",           0,                              NULL  },
{ 1, "Dimensions in &Millimeters",      0,                              NULL  },

{ 0, "&Sketch",                         0,                              NULL  },
{ 1, NULL,                              0,                              NULL  },
{ 1, "To&ggle Construction\tG",         0,                              NULL  },

{ 0, "&Constrain",                      0,                              NULL  },
{ 1, "S&ymmetric\tY",                   0,                              NULL  },

{ 0, "&Help",                           0,                              NULL  },
{ 1, "&About\t",                        0,                              NULL  },
{ -1  },
};

void GraphicsWindow::Init(void) {
    memset(this, 0, sizeof(*this));

    offset.x = offset.y = offset.z = 0;
    scale = 1;
    projRight.x = 1; projRight.y = projRight.z = 0;
    projUp.y = 1; projUp.z = projUp.x = 0;

    show2dCsyss = true;
    showAxes = true;
    showPoints = true;
    showAllGroups = true;
    showConstraints = true;
}

void GraphicsWindow::NormalizeProjectionVectors(void) {
    Vector norm = projRight.Cross(projUp);
    projUp = norm.Cross(projRight);

    projUp = projUp.ScaledBy(1/projUp.Magnitude());
    projRight = projRight.ScaledBy(1/projRight.Magnitude());
}

Point2d GraphicsWindow::ProjectPoint(Vector p) {
    p = p.Plus(offset);

    Point2d r;
    r.x = p.Dot(projRight) * scale;
    r.y = p.Dot(projUp) * scale;
    return r;
}

void GraphicsWindow::MenuView(MenuId id) {
    switch(id) {
        case MNU_ZOOM_IN:
            SS.GW.scale *= 1.2;
            break;

        case MNU_ZOOM_OUT:
            SS.GW.scale /= 1.2;
            break;

        case MNU_ZOOM_TO_FIT:
            break;

        case MNU_ORIENT_ONTO:
            SS.GW.GroupSelection();
            if(SS.GW.gs.n == 1 && SS.GW.gs.csyss == 1) {
                Entity *e = SS.entity.FindById(SS.GW.gs.entity[0]);
                double q[4];
                for(int i = 0; i < 4; i++) {
                    q[i] = SS.param.FindById(e->param(i))->val;
                }
                SS.GW.projRight = Vector::RotationU(q[0], q[1], q[2], q[3]);
                SS.GW.projUp = Vector::RotationV(q[0], q[1], q[2], q[3]);
                SS.GW.offset = SS.point.FindById(e->point(16))->GetCoords();
                SS.GW.ClearSelection();
                InvalidateGraphics();
            } else {
                Error("Select plane or coordinate system before orienting.");
            }
            break;

        default: oops();
    }
    InvalidateGraphics();
}

void GraphicsWindow::MenuEdit(MenuId id) {
    switch(id) {
        case MNU_UNSELECT_ALL:
            SS.GW.ClearSelection();
            break;

        default: oops();
    }
}

void GraphicsWindow::MouseMoved(double x, double y, bool leftDown,
            bool middleDown, bool rightDown, bool shiftDown, bool ctrlDown)
{
    Point2d mp = { x, y };

    if(middleDown) {
        hover.Clear();

        double dx = (x - orig.mouse.x) / scale;
        double dy = (y - orig.mouse.y) / scale;

        if(shiftDown) {
            offset.x = orig.offset.x + dx*projRight.x + dy*projUp.x;
            offset.y = orig.offset.y + dx*projRight.y + dy*projUp.y;
            offset.z = orig.offset.z + dx*projRight.z + dy*projUp.z;
        } else if(ctrlDown) {
            double theta = atan2(orig.mouse.y, orig.mouse.x);
            theta -= atan2(y, x);

            Vector normal = orig.projRight.Cross(orig.projUp);
            projRight = orig.projRight.RotatedAbout(normal, theta);
            projUp = orig.projUp.RotatedAbout(normal, theta);

            NormalizeProjectionVectors();
        } else {
            double s = 0.3*(PI/180); // degrees per pixel
            projRight = orig.projRight.RotatedAbout(orig.projUp, -s*dx);
            projUp = orig.projUp.RotatedAbout(orig.projRight, s*dy);

            NormalizeProjectionVectors();
        }

        orig.projRight = projRight;
        orig.projUp = projUp;
        orig.offset = offset;
        orig.mouse.x = x;
        orig.mouse.y = y;

        InvalidateGraphics();
    } else {
        // No mouse buttons are pressed. We just need to do our usual hit
        // testing, to see if anything ought to be hovered.
        Selection s;
        HitTestMakeSelection(mp, &s);
        if(!s.Equals(&hover)) {
            hover = s;
            InvalidateGraphics();
        }
    }
}

bool GraphicsWindow::Selection::Equals(Selection *b) {
    if(point.v !=  b->point.v)  return false;
    if(entity.v != b->entity.v) return false;
    return true;
}
bool GraphicsWindow::Selection::IsEmpty(void) {
    if(point.v)  return false;
    if(entity.v) return false;
    return true;
}
void GraphicsWindow::Selection::Clear(void) {
    point.v = entity.v = 0;
}
void GraphicsWindow::Selection::Draw(void) {
    if(point.v)  SS.point. FindById(point )->Draw();
    if(entity.v) SS.entity.FindById(entity)->Draw();
}

void GraphicsWindow::HitTestMakeSelection(Point2d mp, Selection *dest) {
    int i;
    double d, dmin = 1e12;

    dest->point.v = 0;
    dest->entity.v = 0;

    // Do the points
    for(i = 0; i < SS.entity.elems; i++) {
        d = SS.entity.elem[i].t.GetDistance(mp);
        if(d < 10 && d < dmin) {
            dest->point.v = 0;
            dest->entity = SS.entity.elem[i].t.h;
        }
    }

    // Entities
    for(i = 0; i < SS.point.elems; i++) {
        d = SS.point.elem[i].t.GetDistance(mp);
        if(d < 10 && d < dmin) {
            dest->entity.v = 0;
            dest->point = SS.point.elem[i].t.h;
        }
    }
}

void GraphicsWindow::ClearSelection(void) {
    for(int i = 0; i < MAX_SELECTED; i++) {
        selection[i].Clear();
    }
    InvalidateGraphics();
}

void GraphicsWindow::GroupSelection(void) {
    gs.points = gs.entities = 0;
    gs.csyss = 0;
    gs.n = 0;
    int i;
    for(i = 0; i < MAX_SELECTED; i++) {
        Selection *s = &(selection[i]);
        if(s->point.v) {
            gs.point[(gs.points)++] = s->point;
            (gs.n)++;
        }
        if(s->entity.v) {
            gs.entity[(gs.entities)++] = s->entity;
            (gs.n)++;

            Entity *e = SS.entity.FindById(s->entity);
            if(e->type == Entity::CSYS_2D) {
                (gs.csyss)++;
            }
        }
    }
}

void GraphicsWindow::MouseMiddleDown(double x, double y) {
    orig.offset = offset;
    orig.projUp = projUp;
    orig.projRight = projRight;
    orig.mouse.x = x;
    orig.mouse.y = y;
}

void GraphicsWindow::MouseLeftDown(double x, double y) {
    // Make sure the hover is up to date.
    MouseMoved(x, y, false, false, false, false, false);

    if(!hover.IsEmpty()) {
        int i;
        for(i = 0; i < MAX_SELECTED; i++) {
            if(selection[i].Equals(&hover)) {
                selection[i].Clear();
                goto done;
            }
        }
        for(i = 0; i < MAX_SELECTED; i++) {
            if(selection[i].IsEmpty()) {
                selection[i] = hover;
                goto done;
            }
        }
        // I guess we ran out of slots, oh well.
done:
        InvalidateGraphics();
    }
}

void GraphicsWindow::MouseScroll(double x, double y, int delta) {
    double offsetRight = offset.Dot(projRight);
    double offsetUp = offset.Dot(projUp);

    double righti = x/scale - offsetRight;
    double upi = y/scale - offsetUp;

    if(delta > 0) {
        scale *= 1.2;
    } else {
        scale /= 1.2;
    }

    double rightf = x/scale - offsetRight;
    double upf = y/scale - offsetUp;

    offset = offset.Plus(projRight.ScaledBy(rightf - righti));
    offset = offset.Plus(projUp.ScaledBy(upf - upi));

    InvalidateGraphics();
}

void GraphicsWindow::ToggleBool(int link, DWORD v) {
    bool *vb = (bool *)v;
    *vb = !*vb;

    SS.GenerateForUserInterface();
    InvalidateGraphics();
    SS.TW.Show();
}

void GraphicsWindow::ToggleAnyDatumShown(int link, DWORD v) {
    bool t = !(SS.GW.show2dCsyss && SS.GW.showAxes && SS.GW.showPoints);
    SS.GW.show2dCsyss = t;
    SS.GW.showAxes = t;
    SS.GW.showPoints = t;

    SS.GenerateForUserInterface();
    InvalidateGraphics();
    SS.TW.Show();
}

void GraphicsWindow::Paint(int w, int h) {
    width = w; height = h;

    glViewport(0, 0, w, h);

    glMatrixMode(GL_PROJECTION); 
    glLoadIdentity();

    glMatrixMode(GL_MODELVIEW); 
    glLoadIdentity();

    glScaled(scale*2.0/w, scale*2.0/h, 0);

    double tx = projRight.Dot(offset);
    double ty = projUp.Dot(offset);
    double mat[16];
    MakeMatrix(mat, projRight.x,    projRight.y,    projRight.z,    tx,
                    projUp.x,       projUp.y,       projUp.z,       ty,
                    0,              0,              0,              0,
                    0,              0,              0,              1);
    glMultMatrixd(mat);

    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
    glEnable(GL_BLEND);
    glEnable(GL_LINE_SMOOTH);
    glEnable(GL_DEPTH_TEST); 
    glHint(GL_LINE_SMOOTH_HINT, GL_NICEST);

    glClearIndex((GLfloat)0);
    glClearDepth(1.0); 
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); 


    int i;

    // First, draw the entire scene.
    glColor3f(1, 1, 1);
    for(i = 0; i < SS.entity.elems; i++) {
        SS.entity.elem[i].t.Draw();
    }
    glColor3f(0, 0.8f, 0);
    for(i = 0; i < SS.point.elems; i++) {
        SS.point.elem[i].t.Draw();
    }

    // Then redraw whatever the mouse is hovering over, highlighted. Have
    // to disable the depth test, so that we can overdraw.
    glDisable(GL_DEPTH_TEST); 
    glColor3f(1, 1, 0);
    hover.Draw();

    // And finally draw the selection, same mechanism.
    glColor3f(1, 0, 0);
    for(i = 0; i < MAX_SELECTED; i++) {
        selection[i].Draw();
    }
}