/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.
Copyright (C) 2007 HermitWorks Entertainment Corporation

This file is part of the Space Trader source code.

The Space Trader source code 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 2 of the License,
or (at your option) any later version.

The Space Trader source code 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 the Space Trader source code; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
===========================================================================
*/

#include "tr_local.h"

#define	LL(x) x=LittleLong(x)

static qboolean R_LoadMD3 (model_t *mod, int lod, void *buffer, const char *name );

model_t	*loadmodel;

/*
** R_GetModelByHandle
*/
model_t	*R_GetModelByHandle( qhandle_t index )
{
	model_t		*mod;

	// out of range gets the defualt model
	if( index < 1 || index >= tr.numModels )
		return tr.models[0];

	mod = tr.models[index];

	return mod;
}

//===============================================================================

/*
** R_AllocModel
*/
model_t *R_AllocModel( void ) {
	model_t		*mod;

	if ( tr.numModels == MAX_MOD_KNOWN ) {
		return NULL;
	}

	mod = ri.Hunk_Alloc( sizeof( *tr.models[tr.numModels] ), h_low );
	mod->index = tr.numModels;
	tr.models[tr.numModels] = mod;
	tr.numModels++;

	return mod;
}

/*
====================
RE_RegisterModel

Loads in a model for the given name

Zero will be returned if the model fails to load.
An entry will be retained for failed models as an
optimization to prevent disk rescanning if they are
asked for again.
====================
*/
qhandle_t Q_EXTERNAL_CALL RE_RegisterModel( const char *name ) {
	model_t		*mod;
	unsigned	*buf;
	int			lod;
	int			ident;
	qboolean	loaded;
	qhandle_t	hModel;
	int			numLoaded;

	if ( !name || !name[0] ) {
		ri.Printf( PRINT_ALL, "RE_RegisterModel: NULL name\n" );
		return 0;
	}

	if ( strlen( name ) >= MAX_QPATH ) {
		ri.Printf( PRINT_ERROR, "Model name exceeds MAX_QPATH\n" );
		return 0;
	}

	//
	// search the currently loaded models
	//
	for ( hModel = 1 ; hModel < tr.numModels; hModel++ ) {
		mod = tr.models[hModel];
		if ( !strcmp( mod->name, name ) ) {
			if( mod->type == MOD_BAD ) {
				return 0;
			}
			return hModel;
		}
	}

	// allocate a new model_t

	if ( ( mod = R_AllocModel() ) == NULL ) {
		ri.Printf( PRINT_WARNING, "RE_RegisterModel: R_AllocModel() failed for '%s'\n", name);
		return 0;
	}

	// only set the name after the model has been successfully loaded
	Q_strncpyz( mod->name, name, sizeof( mod->name ) );


	// make sure the render thread is stopped
	R_SyncRenderThread();

	mod->numLods = 0;

	if( Q_stricmp( name + strlen( name ) - 4, ".x42" ) == 0 )
	{
		qboolean succeeded;
		int len = ri.FS_ReadFile( name, (void **)&buf );
		if( !buf )
			goto fail;

		succeeded = R_LoadX42( mod, buf, len, name );

		ri.FS_FreeFile( buf );

		if( !succeeded )
			goto fail;

		return mod->index;
	}
	else
	{
		numLoaded = 0;

		for( lod = MD3_MAX_LODS - 1 ; lod >= 0 ; lod-- )
		{
			char filename[1024];

			strcpy( filename, name );

			if ( lod != 0 ) {
				char namebuf[80];

				if ( strrchr( filename, '.' ) ) {
					*strrchr( filename, '.' ) = 0;
				}
				sprintf( namebuf, "_%d.md3", lod );
				strcat( filename, namebuf );
			}

			ri.FS_ReadFile( filename, (void **)&buf );
			if ( !buf ) {
				continue;
			}
			
			loadmodel = mod;
			
			ident = LittleLong(*(unsigned *)buf);
			if ( ident != MD3_IDENT ) {
				ri.Printf (PRINT_WARNING,"RE_RegisterModel: unknown fileid for %s\n", name);
				goto fail;
			}

			loaded = R_LoadMD3( mod, lod, buf, name );
			
			ri.FS_FreeFile (buf);

			if ( !loaded ) {
				if ( lod == 0 ) {
					goto fail;
				} else {
					break;
				}
			} else {
				mod->numLods++;
				numLoaded++;
				// if we have a valid model and are biased
				// so that we won't see any higher detail ones,
				// stop loading them
	//			if ( lod <= r_lodbias->integer ) {
	//				break;
	//			}
			}
		}

		if ( numLoaded ) {
			// duplicate into higher lod spots that weren't
			// loaded, in case the user changes r_lodbias on the fly
			for ( lod-- ; lod >= 0 ; lod-- ) {
				mod->numLods++;
				mod->md3[lod] = mod->md3[lod+1];
			}

			return mod->index;
		}
#ifdef _DEBUG
		else {
			ri.Printf (PRINT_WARNING,"RE_RegisterModel: couldn't load %s\n", name);
		}
#endif
	}

fail:
	// we still keep the model_t around, so if the model name is asked for
	// again, we won't bother scanning the filesystem
	mod->type = MOD_BAD;
	return 0;
}


/*
=================
R_LoadMD3
=================
*/
static qboolean R_LoadMD3 (model_t *mod, int lod, void *buffer, const char *mod_name ) {
	int					i, j;
	md3Header_t			*pinmodel;
    md3Frame_t			*frame;
	md3Surface_t		*surf;
	md3Shader_t			*shader;
	md3Triangle_t		*tri;
	md3St_t				*st;
	md3XyzNormal_t		*xyz;
	md3Tag_t			*tag;
	int					version;
	int					size;

	pinmodel = (md3Header_t *)buffer;

	version = LittleLong (pinmodel->version);
	if (version != MD3_VERSION) {
		ri.Printf( PRINT_WARNING, "R_LoadMD3: %s has wrong version (%i should be %i)\n",
				 mod_name, version, MD3_VERSION);
		return qfalse;
	}

	mod->type = MOD_MESH;
	size = LittleLong(pinmodel->ofsEnd);
	mod->dataSize += size;
	mod->md3[lod] = ri.Hunk_Alloc( size, h_low );

	Com_Memcpy (mod->md3[lod], buffer, LittleLong(pinmodel->ofsEnd) );

    LL(mod->md3[lod]->ident);
    LL(mod->md3[lod]->version);
    LL(mod->md3[lod]->numFrames);
    LL(mod->md3[lod]->numTags);
    LL(mod->md3[lod]->numSurfaces);
    LL(mod->md3[lod]->ofsFrames);
    LL(mod->md3[lod]->ofsTags);
    LL(mod->md3[lod]->ofsSurfaces);
    LL(mod->md3[lod]->ofsEnd);

	if ( mod->md3[lod]->numFrames < 1 ) {
		ri.Printf( PRINT_WARNING, "R_LoadMD3: %s has no frames\n", mod_name );
		return qfalse;
	}
    
	// swap all the frames
    frame = (md3Frame_t *) ( (byte *)mod->md3[lod] + mod->md3[lod]->ofsFrames );
    for ( i = 0 ; i < mod->md3[lod]->numFrames ; i++, frame++) {
    	frame->radius = LittleFloat( frame->radius );
        for ( j = 0 ; j < 3 ; j++ ) {
            frame->bounds[0][j] = LittleFloat( frame->bounds[0][j] );
            frame->bounds[1][j] = LittleFloat( frame->bounds[1][j] );
	    	frame->localOrigin[j] = LittleFloat( frame->localOrigin[j] );
        }
	}

	// swap all the tags
    tag = (md3Tag_t *) ( (byte *)mod->md3[lod] + mod->md3[lod]->ofsTags );
    for ( i = 0 ; i < mod->md3[lod]->numTags * mod->md3[lod]->numFrames ; i++, tag++) {
        for ( j = 0 ; j < 3 ; j++ ) {
			tag->origin[j] = LittleFloat( tag->origin[j] );
			tag->axis[0][j] = LittleFloat( tag->axis[0][j] );
			tag->axis[1][j] = LittleFloat( tag->axis[1][j] );
			tag->axis[2][j] = LittleFloat( tag->axis[2][j] );
        }
	}

	// swap all the surfaces
	surf = (md3Surface_t *) ( (byte *)mod->md3[lod] + mod->md3[lod]->ofsSurfaces );
	for ( i = 0 ; i < mod->md3[lod]->numSurfaces ; i++) {

        LL(surf->ident);
        LL(surf->flags);
        LL(surf->numFrames);
        LL(surf->numShaders);
        LL(surf->numTriangles);
        LL(surf->ofsTriangles);
        LL(surf->numVerts);
        LL(surf->ofsShaders);
        LL(surf->ofsSt);
        LL(surf->ofsXyzNormals);
        LL(surf->ofsEnd);
		
		if ( surf->numVerts > SHADER_MAX_VERTEXES ) {
			ri.Error (ERR_DROP, "R_LoadMD3: %s has more than %i verts on a surface (%i)",
				mod_name, SHADER_MAX_VERTEXES, surf->numVerts );
		}
		if ( surf->numTriangles*3 > SHADER_MAX_INDEXES ) {
			ri.Error (ERR_DROP, "R_LoadMD3: %s has more than %i triangles on a surface (%i)",
				mod_name, SHADER_MAX_INDEXES / 3, surf->numTriangles );
		}
	
		// change to surface identifier
		surf->ident = SF_MD3;

		// lowercase the surface name so skin compares are faster
		Q_strlwr( surf->name );

		// strip off a trailing _1 or _2
		// this is a crutch for q3data being a mess
		j = strlen( surf->name );
		if ( j > 2 && surf->name[j-2] == '_' ) {
			surf->name[j-2] = 0;
		}

        // register the shaders
        shader = (md3Shader_t *) ( (byte *)surf + surf->ofsShaders );
        for ( j = 0 ; j < surf->numShaders ; j++, shader++ ) {
            shader_t	*sh;

            sh = R_FindShader( shader->name, LIGHTMAP_NONE, qtrue );
			if ( sh->defaultShader ) {
				shader->shaderIndex = 0;
			} else {
				shader->shaderIndex = sh->index;
			}
        }

		// swap all the triangles
		tri = (md3Triangle_t *) ( (byte *)surf + surf->ofsTriangles );
		for ( j = 0 ; j < surf->numTriangles ; j++, tri++ ) {
			LL(tri->indexes[0]);
			LL(tri->indexes[1]);
			LL(tri->indexes[2]);
		}

		// swap all the ST
        st = (md3St_t *) ( (byte *)surf + surf->ofsSt );
        for ( j = 0 ; j < surf->numVerts ; j++, st++ ) {
            st->st[0] = LittleFloat( st->st[0] );
            st->st[1] = LittleFloat( st->st[1] );
        }

		// swap all the XyzNormals
        xyz = (md3XyzNormal_t *) ( (byte *)surf + surf->ofsXyzNormals );
        for ( j = 0 ; j < surf->numVerts * surf->numFrames ; j++, xyz++ ) 
		{
            xyz->xyz[0] = LittleShort( xyz->xyz[0] );
            xyz->xyz[1] = LittleShort( xyz->xyz[1] );
            xyz->xyz[2] = LittleShort( xyz->xyz[2] );

            xyz->normal = LittleShort( xyz->normal );
        }


		// find the next surface
		surf = (md3Surface_t *)( (byte *)surf + surf->ofsEnd );
	}
    
	return qtrue;
}

//=============================================================================

/*
** RE_BeginRegistration
*/
void Q_EXTERNAL_CALL RE_BeginRegistration( vidConfig_t *glconfigOut ) {

	R_Init();

	*glconfigOut = glConfig;

	R_SyncRenderThread();

	tr.viewCluster = -1;		// force markleafs to regenerate
	R_ClearFlares();
	RE_ClearScene();

	tr.registered = qtrue;

	// NOTE: this sucks, for some reason the first stretch pic is never drawn
	// without this we'd see a white flash on a level load because the very
	// first time the level shot would not be drawn
	RE_StretchPic( 0, 0, 0, 0, NULL, 0, 0, 1, 1, 0 );
}

//=============================================================================

/*
===============
R_ModelInit
===============
*/
void R_ModelInit( void ) {
	model_t		*mod;

	// leave a space for NULL model
	tr.numModels = 0;

	mod = R_AllocModel();
	mod->type = MOD_BAD;
}


/*
================
R_Modellist_f
================
*/
void Q_EXTERNAL_CALL R_Modellist_f( void ) {
	int		i, j;
	model_t	*mod;
	int		total;
	int		lods;

	total = 0;
	for ( i = 1 ; i < tr.numModels; i++ ) {
		mod = tr.models[i];
		lods = 1;
		for ( j = 1 ; j < MD3_MAX_LODS ; j++ ) {
			if ( mod->md3[j] && mod->md3[j] != mod->md3[j-1] ) {
				lods++;
			}
		}
		ri.Printf( PRINT_ALL, "%8i : (%i) %s\n",mod->dataSize, lods, mod->name );
		total += mod->dataSize;
	}
	ri.Printf( PRINT_ALL, "%8i : Total models\n", total );

#if	0		// not working right with new hunk
	if ( tr.world ) {
		ri.Printf( PRINT_ALL, "\n%8i : %s\n", tr.world->dataSize, tr.world->name );
	}
#endif
}


//=============================================================================


/*
================
R_GetTag
================
*/
static md3Tag_t *R_GetTag( md3Header_t *mod, int frame, const char *tagName ) {
	md3Tag_t		*tag;
	int				i;

	if ( frame >= mod->numFrames ) {
		// it is possible to have a bad frame while changing models, so don't error
		frame = mod->numFrames - 1;
	}

	tag = (md3Tag_t *)((byte *)mod + mod->ofsTags) + frame * mod->numTags;
	for ( i = 0 ; i < mod->numTags ; i++, tag++ ) {
		if ( !strcmp( tag->name, tagName ) ) {
			return tag;	// found it
		}
	}

	return NULL;
}

/*
================
R_LerpTag
================
*/
int Q_EXTERNAL_CALL R_LerpTag( affine_t *tag, qhandle_t handle, int startFrame, int endFrame, 
					 float frac, const char *tagName ) {
	md3Tag_t	*start, *end;
	int		i;
	float		frontLerp, backLerp;
	model_t		*model;

	model = R_GetModelByHandle( handle );

	if( model->type == MOD_X42 )
		return R_LerpX42Tag( tag, model->x42, startFrame, endFrame, frac, tagName );

	if ( !model->md3[0] ) {
		AxisClear( tag->axis );
		VectorClear( tag->origin );
		return qfalse;
	}

	start = R_GetTag( model->md3[0], startFrame, tagName );
	end = R_GetTag( model->md3[0], endFrame, tagName );
	if ( !start || !end ) {
		AxisClear( tag->axis );
		VectorClear( tag->origin );
		return qfalse;
	}

	frontLerp = frac;
	backLerp = 1.0f - frac;

	for ( i = 0 ; i < 3 ; i++ ) {
		tag->origin[i] = start->origin[i] * backLerp +  end->origin[i] * frontLerp;
		tag->axis[0][i] = start->axis[0][i] * backLerp +  end->axis[0][i] * frontLerp;
		tag->axis[1][i] = start->axis[1][i] * backLerp +  end->axis[1][i] * frontLerp;
		tag->axis[2][i] = start->axis[2][i] * backLerp +  end->axis[2][i] * frontLerp;
	}
	VectorNormalize( tag->axis[0] );
	VectorNormalize( tag->axis[1] );
	VectorNormalize( tag->axis[2] );
	return qtrue;
}


/*
====================
R_ModelBounds
====================
*/
void Q_EXTERNAL_CALL R_ModelBounds( qhandle_t handle, vec3_t mins, vec3_t maxs ) {
	model_t		*model;
	md3Header_t	*header;
	md3Frame_t	*frame;

	model = R_GetModelByHandle( handle );

	if ( model->bmodel ) {
		VectorCopy( model->bmodel->bounds[0], mins );
		VectorCopy( model->bmodel->bounds[1], maxs );
		return;
	}

	if ( !model->md3[0] ) {
		VectorClear( mins );
		VectorClear( maxs );
		return;
	}

	header = model->md3[0];

	frame = (md3Frame_t *)( (byte *)header + header->ofsFrames );

	VectorCopy( frame->bounds[0], mins );
	VectorCopy( frame->bounds[1], maxs );
}