/*
* Descent 3 
* Copyright (C) 2024 Parallax Software
*
* 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 3 of the License, or
* (at your option) any later version.
*
* This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.

--- HISTORICAL COMMENTS FOLLOW ---

 * $Logfile: /DescentIII/Main/editor/HView.cpp $
 * $Revision: 1.1.1.1 $
 * $Date: 2003-08-26 03:57:38 $
 * $Author: kevinb $
 *
 * Code to implement view menu functions
 *
 * $Log: not supported by cvs2svn $
 * 
 * 24    4/30/99 11:18p Matt
 * Limit viewer to terrain bounds when moving the viewer to an external
 * room.
 * 
 * 23    4/29/99 11:51p Matt
 * Improved viewer move functions.
 * 
 * 22    4/17/99 2:42p Matt
 * Set Viewer_moved when a new viewer is selected.
 * 
 * 21    2/28/99 8:11p Matt
 * Fixed problems when at max viewers
 * 
 * 20    1/15/99 7:52p Chris
 * Updated ObjSetPos() to include a f_update_attach_children flag
 * 
 * 19    5/12/98 2:49p Matt
 * Link the room viewer to the terrain, since there's not always a room to
 * put him in.
 * 
 * 18    3/12/98 7:30p Chris
 * Added ObjSetOrient
 * 
 * 17    2/09/98 10:55a Matt
 * When searching for rooms to put the viewer in, don't consider external
 * rooms.
 * 
 * 16    2/05/98 3:11p Matt
 * Don't move the viewer to an external room.
 * 
 * 15    2/05/98 2:57p Matt
 * Changed code to use ObjSetPos()
 * 
 * 14    2/04/98 6:23p Matt
 * Changed object room number to indicate a terrain cell via a flag.  Got
 * rid of the object flag which used to indicate terrain.
 * 
 * 13    1/29/98 5:50p Matt
 * Changed old camera object type to be viewer object (for editor), and
 * now camera objects will just be for game cameras.
 * 
 * 12    1/21/98 1:08p Matt
 * Made SetViewMode() not take new_viewer parm, since it's not needed
 * after my revamp of the editor view system.
 * 
 * 11    1/21/98 12:33p Matt
 * Revamped viewer system
 * 
 * 10    1/19/98 10:04a Matt
 * Removed unused function
 * 
 * 9     11/14/97 1:01p Matt
 * When can't find camera, don't just make one in the center of room 0.
 * Instead, find the first room that's used.
 * 
 * 8     9/17/97 11:51a Samir
 * BIG SEGMENT RIPOUT
 * 
 * 7     8/25/97 2:50p Chris
 * Improve AABB/object movement code.
 * 
 * 6     8/04/97 7:39p Matt
 * Pass new room number to ObjSetPos()
 * 
 * 5     8/04/97 12:43p Matt
 * Added SetViewerFromRoomFace()
 * 
 * 4     7/22/97 7:08p Matt
 * Cleaned up D3EditState, moving some vars in and some out, and renaming
 * and changing a few others
 * 
 * 4     4/01/97 11:00p Matt
 * Changed editor to keep a viewer object (type camera) seperate from the
 * player object.  This camera, and not the player, is now moved by
 * slewing, the C key, etc.  When going into the game, the viewer position
 * & orientation are copied to the player.  When going back to the editor,
 * the player position is copied to the viewer, and the player object is
 * reset to its start location.
 * 
 * 3     3/31/97 5:58p Matt
 * Revamped mine update flags
 * 
 * 2     3/17/97 2:26p Matt
 * Added function to set player view from curseg/curside
 * 
 * 1     3/17/97 1:47p Matt
 *
 * $NoKeywords: $
 */

#include "mainfrm.h"
#include "HView.h"
#include "d3edit.h"
#include "terrain.h"
#include "erooms.h"
#include "editor.h"

#define FACE_VIEW_DIST  5.0

//Set the viewer in the specified room facing the specified face
//If room_center is true, put viewer at the center of the room facing the face
//If room_center is false, put the viewer directly in front of the selected face
//If the room is external, put the viewer a distance away from the room, 
//facing either the center (if room_center is true) or the specified face
void SetViewerFromRoomFace(room *roomp,int facenum,bool room_center)
{
	vector	vp,newpos;
	matrix	orient;
	int roomnum;
	bool outside_mine = 0;

	ComputeCenterPointOnFace(&vp,roomp,facenum);
	roomnum = ROOMNUM(roomp);

	if (room_center) {

		//Get position
		ComputeRoomCenter(&newpos,roomp);

		if (roomp->flags & RF_EXTERNAL) {
			vector t;
			float rad = ComputeRoomBoundingSphere(&t,roomp);

			newpos.z -= rad * 1.5;

			if(newpos.x < 1.0)
				newpos.x = 1.0;
			if(newpos.x > TERRAIN_WIDTH * TERRAIN_SIZE - 1.0)
				newpos.x = TERRAIN_WIDTH * TERRAIN_SIZE - 1.0;
			if(newpos.z < 1.0)
				newpos.z = 1.0;
			if(newpos.z > TERRAIN_DEPTH * TERRAIN_SIZE - 1.0) 
				newpos.z = TERRAIN_WIDTH * TERRAIN_SIZE - 1.0;

			orient = Identity_matrix;

			roomnum = GetTerrainRoomFromPos(&newpos);
		}
		else {
			//Get orientation
			vp -= newpos;		//vector from center of room to face
			vm_VectorToMatrix(&orient,&vp,NULL,NULL);
		}
	}
	else {
		face *fp = &roomp->faces[facenum];

		newpos = vp + fp->normal * FACE_VIEW_DIST;

		vector t = -fp->normal;
		vm_VectorToMatrix(&orient,&t,NULL,NULL);

		if (roomp->flags & RF_EXTERNAL) {
			if(newpos.x < 1.0)
				newpos.x = 1.0;
			if(newpos.x > TERRAIN_WIDTH * TERRAIN_SIZE - 1.0)
				newpos.x = TERRAIN_WIDTH * TERRAIN_SIZE - 1.0;
			if(newpos.z < 1.0)
				newpos.z = 1.0;
			if(newpos.z > TERRAIN_DEPTH * TERRAIN_SIZE - 1.0) 
				newpos.z = TERRAIN_WIDTH * TERRAIN_SIZE - 1.0;
			roomnum = GetTerrainRoomFromPos(&newpos);
		}
		else {
			int new_roomnum = FindPointRoom(&newpos);
			if (new_roomnum == -1)
				outside_mine = 1;
			else
				roomnum = new_roomnum;
		}
	}

	//Reset viewer
	if (Editor_view_mode == VM_ROOM) {
		Viewer_object->pos = newpos; 
		Viewer_object->orient = orient;
	}
	else
		MoveViewer(&newpos,roomnum,&orient);

	if (outside_mine)
		Viewer_object->flags |= OF_OUTSIDE_MINE;

	Viewer_moved = 1;
}

//max viewers for each type
#define MAX_VIEWERS		20

//The viewer in room mode has this ID
#define ROOM_VIEWER_ID	MAX_VIEWERS

//Finds a specific viewer object it one exists
//Parameters:	id - which viewer id
//Returns:		object number of a viewer object, or -1 if none
int FindViewerObject(int id)
{
	object *objp;
	int objnum=-1;

	//trace through all objects looking for viewer
	for (objnum=0,objp=Objects;objnum<=Highest_object_index;objnum++,objp++)
		if ((objp->type == OBJ_VIEWER) && (objp->id == id))
				break;

	if (objnum <= Highest_object_index)		//found one
		return objnum;
	else
		return -1;
}


//Finds a viewer object if one exists.  
//Starts looking at the specified id and searches through all possible ids
//Parameters:	id - which viewer id
//					view_mode - if -1, find any viewer, else find one that matches view mode
//Returns:		object number of a viewer object, or -1 if none
int FindNextViewerObject(int id,int view_mode)
{
	int i;
	int objnum;
	int terrain_flag;

	if (id == -1)
		id = 0;

	ASSERT((id >= 0) && (id <= MAX_VIEWERS));

	//Get flags
	terrain_flag = (view_mode == VM_TERRAIN);

	//Try all viewer id's, starting at the one passed in
	for (i=0;i<MAX_VIEWERS;i++) {
		int check_id = ((id + i) % MAX_VIEWERS);

		objnum = FindViewerObject(check_id);

		if ((objnum != -1) && ((view_mode == -1) || ((OBJECT_OUTSIDE(&Objects[objnum]) != 0) == terrain_flag)))
			break;
	}

	if (i == MAX_VIEWERS)		//didn't find one
		return -1;

	return objnum;
}


//Creates a viewer object of the specified type
//Parameters:	view_mode - mine,terrain,or room.  See constants in 3dedit.h
//					pos - initial position of this object
//					roomnum - initial room/terrain cell of this object
//Returns:		object number of the object created, or -1 if at max number of viewers of that type
int CreateViewerObject(int view_mode,vector *pos,int roomnum)
{
	int id;
	object *objp;
	int objnum=-1;

	if (view_mode == VM_ROOM) {
		id = ROOM_VIEWER_ID;

		for (objnum=0,objp=Objects;objnum<=Highest_object_index;objnum++,objp++)
			if ((objp->type == OBJ_VIEWER) && (objp->id == id))
				return -1;			//this one already used
	}
	else {
		//for each id, loop through all objects to see if it's used
		for (id=0;id<MAX_VIEWERS;id++) {
			for (objnum=0,objp=Objects;objnum<=Highest_object_index;objnum++,objp++)
				if ((objp->type == OBJ_VIEWER) && (objp->id == id))
					break;			//this one already used
			if (objnum > Highest_object_index)		//didn't find objec twith this id
				break;
		}

		if (id == MAX_VIEWERS)		//no unused viewer id's
			return -1;
	}

	//Create the new object
  	objnum = ObjCreate(OBJ_VIEWER,id,roomnum,pos,NULL);

  	if (objnum == -1) {
		Int3();
		return -1;
	}

	return objnum;
}

//Returns the number (not the id) of the current viewer, in the range 0..MAX_VIEWERS
int GetViewerNum()
{
	ASSERT(Editor_view_mode != VM_ROOM);

	return Viewer_object->id;
}


//Set the specified object to be the viewer
void SetViewer(int objnum)
{
	Viewer_object = &Objects[objnum];

	if (Editor_view_mode != VM_ROOM)
		Editor_viewer_id = Viewer_object->id;

	if ((Editor_view_mode == VM_MINE) && OBJECT_OUTSIDE(Viewer_object))
		SetViewMode(VM_TERRAIN);

	if ((Editor_view_mode == VM_TERRAIN) && !(OBJECT_OUTSIDE(Viewer_object)))
		SetViewMode(VM_MINE);

	State_changed = Viewer_moved = 1;
}


//Creates a new viewer object.  Copies position & orientation from the current viewer
void CreateNewViewer()
{
	int objnum;
	
	objnum = CreateViewerObject(Editor_view_mode,&Viewer_object->pos,Viewer_object->roomnum);

	if (objnum == -1) {
		OutrageMessageBox("Cannot create new viewer: you already have the maximum number of viewers.");
		return;
	}

	ObjSetOrient(&Objects[objnum], &Viewer_object->orient);

	SetViewer(objnum);

	EditorStatus("Viewer %d created.",GetViewerNum());

	World_changed = 1;
}

//Select next viewer
void SelectNextViewer()
{
	int objnum;

	if (Editor_view_mode == VM_ROOM) {
		EditorStatus("There is only one viewer in Room View");
		return;
	}

	ASSERT(Viewer_object != NULL);

	objnum = FindNextViewerObject(Viewer_object->id + 1,-1);

	ASSERT(objnum != -1);

	if (objnum == OBJNUM(Viewer_object)) {
		EditorStatus("No other viewers.");
		return;
	}

	SetViewer(objnum);
	EditorStatus("Viewer %d selected.",GetViewerNum());
}

//Deletes the current viewer object
void DeleteViewer()
{
	int objnum,old_num;

	if (Viewer_object->id == ROOM_VIEWER_ID) {
		OutrageMessageBox("You cannot delete the Room viewer.");
		return;
	}

	objnum = FindNextViewerObject(Viewer_object->id + 1,-1);

	ASSERT(objnum != -1);

	if (objnum == OBJNUM(Viewer_object)) {		//couldn't find another viewer
		OutrageMessageBox("You cannot delete your only viewer.");
		return;
	}

	old_num = GetViewerNum();

	//Kill the old viewer
	ObjDelete(OBJNUM(Viewer_object));

	//Set the new viewer
	SetViewer(objnum);

	EditorStatus("Viewer %d deleted.  Viewer %d selected.",old_num,GetViewerNum());

	World_changed = 1;
}

//Sets the viewer object for the editor, creating if not already in mine
//Keeps seperate viewer objects for mine & terrain views
void SetEditorViewer()
{
	int objnum,roomnum;

	//First, see if a camera object already exists in the level
	if (Editor_view_mode == VM_ROOM)
		objnum = FindViewerObject(ROOM_VIEWER_ID);
	else
		objnum = FindNextViewerObject(Editor_viewer_id,Editor_view_mode);

	//If no viewer object, create one
	if (objnum == -1) {
		vector pos;

		//get position for viewer
		if (Editor_view_mode == VM_TERRAIN) {			//if terrain, put viewer at center of world
	  		pos.x = TERRAIN_SIZE * TERRAIN_WIDTH/2;
  			pos.y = Terrain_seg[0].y+30;
  			pos.z = TERRAIN_SIZE*TERRAIN_DEPTH/2;
			roomnum = MAKE_ROOMNUM(0);		//any value ok, so long as it has terrain flag
	  	}
		else if (Editor_view_mode == VM_MINE) {		//if mine, put in center of any room
			for (roomnum=0;roomnum<=Highest_room_index;roomnum++)
				if (Rooms[roomnum].used && !(Rooms[roomnum].flags & RF_EXTERNAL)) {
		  			ComputeRoomCenter(&pos,&Rooms[roomnum]);
					break;
				}
			ASSERT(roomnum <= Highest_room_index);
		}
		else if (Editor_view_mode == VM_ROOM) {		//if room, put at 0,0,0
			vm_MakeZero(&pos);
			roomnum = MAKE_ROOMNUM(0);
		}
		else
			Int3();	//unknown view mode

		objnum = CreateViewerObject(Editor_view_mode,&pos,roomnum);

		//If no free viewer slots, grab any viewer and move it
		if (objnum == -1) {
			ASSERT(Viewer_object != NULL);
			if (Viewer_object->type == OBJ_VIEWER)
				objnum = OBJNUM(Viewer_object);
			else {
				objnum = FindNextViewerObject(Editor_viewer_id,-1);
				ASSERT(objnum != -1);
			}
			ObjSetPos(&Objects[objnum],&pos,roomnum,NULL,true);
		}
	}

	ASSERT(objnum != -1);
	SetViewer(objnum);
}

//Moves the room viewer to the origin, if there is a room viewer
void ResetRoomViewer()
{
	int objnum = FindViewerObject(ROOM_VIEWER_ID);

	if (objnum != -1) {
		vm_MakeZero(&Objects[objnum].pos);
		ObjSetOrient(&Objects[objnum], &Identity_matrix);
	}
}