/* Copyright (c) 2001, Stanford University
 * All rights reserved
 *
 * See the file LICENSE.txt for information on redistributing this software.
 */

#include "packer.h"
#include "cr_error.h"

static GLboolean __handleLightData(GLenum light, GLenum pname, const GLfloat *params)
{
    CR_GET_PACKER_CONTEXT(pc);
    unsigned int packet_length = sizeof(int) + sizeof(light) + sizeof(pname);
    unsigned int params_length = 0;
    unsigned char *data_ptr;
    switch(pname)
    {
        case GL_AMBIENT:
        case GL_DIFFUSE:
        case GL_SPECULAR:
        case GL_POSITION:
            params_length = 4*sizeof(*params);
            break;
        case GL_SPOT_DIRECTION:
            params_length = 3*sizeof(*params);
            break;
        case GL_SPOT_EXPONENT:
        case GL_SPOT_CUTOFF:
        case GL_CONSTANT_ATTENUATION:
        case GL_LINEAR_ATTENUATION:
        case GL_QUADRATIC_ATTENUATION:
            params_length = sizeof(*params);
            break;
        default:
            __PackError(__LINE__, __FILE__, GL_INVALID_ENUM,
                                     "crPackLight(bad pname)");
            return GL_FALSE;
    }
    packet_length += params_length;
    CR_GET_BUFFERED_POINTER(pc, packet_length);
    WRITE_DATA(0, int, packet_length);
    WRITE_DATA(sizeof(int) + 0, GLenum, light);
    WRITE_DATA(sizeof(int) + 4, GLenum, pname);
    WRITE_DATA(sizeof(int) + 8, GLfloat, params[0]);
    if (params_length > sizeof(*params)) 
    {
        WRITE_DATA(sizeof(int) + 12, GLfloat, params[1]);
        WRITE_DATA(sizeof(int) + 16, GLfloat, params[2]);
    }
    if (params_length > 3*sizeof(*params)) 
    {
        WRITE_DATA(sizeof(int) + 20, GLfloat, params[3]);
    }
    return GL_TRUE;
}

void PACK_APIENTRY crPackLightfv (GLenum light, GLenum pname, const GLfloat *params)
{
    CR_GET_PACKER_CONTEXT(pc);
    if (__handleLightData(light, pname, params))
        WRITE_OPCODE(pc, CR_LIGHTFV_OPCODE);
    CR_UNLOCK_PACKER_CONTEXT(pc);
}

void PACK_APIENTRY crPackLightiv (GLenum light, GLenum pname, const GLint *params)
{
    /* floats and ints are the same size, so the packing should be the same */
    CR_GET_PACKER_CONTEXT(pc);
    if (__handleLightData(light, pname, (const GLfloat *) params))
        WRITE_OPCODE(pc, CR_LIGHTIV_OPCODE);
    CR_UNLOCK_PACKER_CONTEXT(pc);
}

static GLboolean __handleLightModelData(GLenum pname, const GLfloat *params)
{
    CR_GET_PACKER_CONTEXT(pc);
    unsigned int packet_length = sizeof(int) + sizeof(pname);
    unsigned int params_length = 0;
    unsigned char *data_ptr;
    switch(pname)
    {
        case GL_LIGHT_MODEL_AMBIENT:
            params_length = 4*sizeof(*params);
            break;
        case GL_LIGHT_MODEL_TWO_SIDE:
        case GL_LIGHT_MODEL_LOCAL_VIEWER:
            params_length = sizeof(*params);
            break;
        default:
            __PackError(__LINE__, __FILE__, GL_INVALID_ENUM,
                                     "crPackLightModel(bad pname)");
            return GL_FALSE;
    }
    packet_length += params_length;
    CR_GET_BUFFERED_POINTER(pc, packet_length);
    WRITE_DATA(0, int, packet_length);
    WRITE_DATA(sizeof(int) + 0, GLenum, pname);
    WRITE_DATA(sizeof(int) + 4, GLfloat, params[0]);
    if (params_length > sizeof(*params))
    {
        WRITE_DATA(sizeof(int) + 8, GLfloat, params[1]);
        WRITE_DATA(sizeof(int) + 12, GLfloat, params[2]);
        WRITE_DATA(sizeof(int) + 16, GLfloat, params[3]);
    }
    return GL_TRUE;
}

void PACK_APIENTRY crPackLightModelfv (GLenum pname, const GLfloat *params)
{
    CR_GET_PACKER_CONTEXT(pc);
    if (__handleLightModelData(pname, params))
        WRITE_OPCODE(pc, CR_LIGHTMODELFV_OPCODE);
    CR_UNLOCK_PACKER_CONTEXT(pc);
}

void PACK_APIENTRY crPackLightModeliv (GLenum pname, const GLint *params)
{
    /* floats and ints are the same size, so the packing should be the same */
    CR_GET_PACKER_CONTEXT(pc);
    if (__handleLightModelData(pname, (const GLfloat *) params))
        WRITE_OPCODE(pc, CR_LIGHTMODELIV_OPCODE);
    CR_UNLOCK_PACKER_CONTEXT(pc);
}