#include <gl/gl.h>
#include <gl/device.h>

#include "Application.hxx"

Application *MyApp;

extern "C" {
  #include <stdlib.h>
}

int callbackSelectStory(char * story);

int main(int argc, char *argv[]) {
  MyApp = new Application();
  MyApp->make_objects();
  MyApp->Loop();

  pfExit();
  return 0;
}

Application::Application() {
  // Initialize Performer
  pfInit();
  pfMultiprocess(PFMP_APPCULLDRAW);
  pfConfig();
  pfuInitUtil();

  pipe = new Pipe(1280, 1024);
  pipe->Setup();
  pick = new Pick(pipe->GetChan());

  element_list = new List();
}

void Application::Loop() { 
  while(process_event()) { 
    pipe->UpdateCam();
    pfFrame();
  }
}

// configuration of the placement and look of things

// blur and transparencies of stories in the back, front
float backBlur = 0.85;
float backTrans = 0.37;
float frontBlur = 0;
float frontTrans = 1.0;

// table of where the 5 stories go
// the 0th position is the front-and-center story.
float xpos[5] = { -12, -44, -24, 2, 22};
float ypos[5] = { 88, 110, 110, 110, 110 };
float zpos[5] = { 42, -10, 67, 67, -10 };

int positionIndices[5] = { 0, 1, 2, 3, 4 };

// colours for the five stories
float rcol[5] = { 1.0, 1.0, 0.5, 1.0, 0.7 };
float gcol[5] = { 1.0, 0.5, 1.0, 0.7, 0.7 };
float bcol[5] = { 0.5, 1.0, 1.0, 0.7, 1.0 };

// workhorse function - handle when a story is selected
void Application::selectStory(int newStory) {
  float backx, backy, backz, frontx, fronty, frontz;
  int numFrames = 10;
  int i;
  
  if (newStory == selectedStory)		  // no change really
    return;

  // this doesn't work for some reason
  // stories[newStory]->GetPosition(&backx, &backy, &backz);

  // the new story is going to go to the front
  frontx = xpos[0];
  fronty = ypos[0];
  frontz = zpos[0];

  // the old story is going where the new story was before
  backx = xpos[positionIndices[newStory]];
  backy = ypos[positionIndices[newStory]];
  backz = zpos[positionIndices[newStory]];

  // the old selected story is now where the new one is now
  positionIndices[selectedStory] = positionIndices[newStory];
  
  // printf("Swapping (%f,%f,%f) and (%f,%f,%f)\n", backx, backy, backz, frontx, fronty, frontz);
  
  // animate swapping the two stories
  for (i = 0; i <= numFrames; i++) {
    float k = (float)i / (float)numFrames;	  // how far along?
    
    // make the old story blurry and put it where the one we selected is
    stories[selectedStory]->SetTransparency(frontTrans*(1-k) + backTrans*k);
    stories[selectedStory]->SetBlur(frontBlur*(1-k) + backBlur*k);
    stories[selectedStory]->SetPosition(frontx * (1-k) + backx * k,
					fronty * (1-k) + backy * k,
					frontz * (1-k) + backz * k);
  
    // now bring the new story to the front and sharp
    stories[newStory]->SetTransparency(backTrans*(1-k) + frontTrans*k);
    stories[newStory]->SetBlur(backBlur*(1-k) + frontBlur*k);
    stories[newStory]->SetPosition(backx * (1-k) + frontx * k,
				   backy * (1-k) + fronty * k,
				   backz * (1-k) + frontz * k);

    pfFrame();
  }

  selectedStory = newStory;
}

void Application::make_objects() {
  int i;
  char file[255];

  // make 5 story objects and put them in the right places
  // also make them clickable
  for (i = 0; i < 5; i++) {
    sprintf(file, "text/story%d", i+1);
    stories[i] = new Story(file, "Futura_book", "Futura_bold");
    stories[i]->SetColor(rcol[i], gcol[i], bcol[i]);
    stories[i]->SetPosition(xpos[i], ypos[i], zpos[i]);
    stories[i]->SetBlur(backBlur);
    stories[i]->SetTransparency(backTrans);
    stories[i]->AttachFunctionCall(JUSTDOWN, callbackSelectStory, (char *)i);
    AddPickable(stories[i]);
    AddChild(stories[i]);
  }

  selectedStory = 0;
  stories[0]->SetTransparency(frontTrans);
  stories[0]->SetBlur(frontBlur);
  // the position was set above
}

int Application::process_event () {
  if (getbutton (QKEY))
    return 0;

  pick->UpdateMouse();
  if (pick->ChanPick()) {
    SendMessage(pick->hit_geode, pick->mouse_state);
  }

  // number keys pick stories absolutely
  if (getbutton(ONEKEY)) {
    selectStory(0);
  }
  if (getbutton(TWOKEY)) {
    selectStory(1);
  }
  if (getbutton(THREEKEY)) {
    selectStory(2);
  }
  if (getbutton(FOURKEY)) {
    selectStory(3);
  }
  if (getbutton(FIVEKEY)) {
    selectStory(4);
  }
    
  if (getbutton (XKEY)) {
    if (getbutton (LEFTARROWKEY))
      pipe->cam->xyz[0] += 1.0;
    if (getbutton (RIGHTARROWKEY))
      pipe->cam->xyz[0] -= 1.0;
  }
  if (getbutton (YKEY)) {
    if (getbutton (LEFTARROWKEY))
      pipe->cam->xyz[1] += 1.0;
    if (getbutton (RIGHTARROWKEY))
      pipe->cam->xyz[1] -= 1.0;
  }
  if (getbutton (ZKEY)) {
    if (getbutton (LEFTARROWKEY))
      pipe->cam->xyz[2] += 1.0;
    if (getbutton (RIGHTARROWKEY))
      pipe->cam->xyz[2] -= 1.0;
  }

  if (getbutton (HKEY)) {
    if (getbutton (LEFTARROWKEY))
      pipe->cam->hpr[0] += 1.0;
    if (getbutton (RIGHTARROWKEY))
      pipe->cam->hpr[0] -= 1.0;
  }
  if (getbutton (PKEY)) {
    if (getbutton (LEFTARROWKEY))
      pipe->cam->hpr[1] += 1.0;
    if (getbutton (RIGHTARROWKEY))
      pipe->cam->hpr[1] -= 1.0;
  }
  if (getbutton (RKEY)) {
    if (getbutton (LEFTARROWKEY))
      pipe->cam->hpr[2] += 1.0;
    if (getbutton (RIGHTARROWKEY))
      pipe->cam->hpr[2] -= 1.0;
  }
  return 1;
}

int Application::AddPickable(Element *e)  {
  element_list->AddToList((void *) e);
  return (1);
}

int Application::SendMessage(pfGeode *hit_geode, int id) {
  List *L;
  Element *element;
  
  for (L = element_list->GetFront(); L != element_list; L = L->GetFront()) {
    element  = (Element *)L->GetItem();
    if (element->MatchGeode(hit_geode)) {
      return (element->CallFunction(id));
    }
  }
  return (0);
}

// C callback: when the mouse is clicked, it carries with it data
// about which story was clicked
int callbackSelectStory(char * story) {
  printf("Story %d selected\n", (int)story);
  MyApp->selectStory((int)story);
  return 1;
}