/**

 * MojoShader; generate shader programs from bytecode of compiled

 *  Direct3D shaders.

 *

 * Please see the file LICENSE.txt in the source's root directory.

 *

 *  This file written by Ryan C. Gordon.

 */

#define __MOJOSHADER_INTERNAL__ 1

#include "mojoshader_internal.h"

static MOJOSHADER_effect MOJOSHADER_out_of_mem_effect = {

    1, &MOJOSHADER_out_of_mem_error, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0

};

static uint32 readui32(const uint8 **_ptr, uint32 *_len)

{

    uint32 retval = 0;

    if (*_len < sizeof (retval))

        *_len = 0;

    else

    {

        const uint32 *ptr = (const uint32 *) *_ptr;

        retval = SWAP32(*ptr);

        *_ptr += sizeof (retval);

        *_len -= sizeof (retval);

    } // else

    return retval;

} // readui32

// !!! FIXME: this is sort of a big, ugly function.

const MOJOSHADER_effect *MOJOSHADER_parseEffect(const char *profile,

                                                const unsigned char *buf,

                                                const unsigned int _len,

                                                const MOJOSHADER_swizzle *swiz,

                                                const unsigned int swizcount,

                                                MOJOSHADER_malloc m,

                                                MOJOSHADER_free f,

                                                void *d)

{

    if ( ((m == NULL) && (f != NULL)) || ((m != NULL) && (f == NULL)) )

        return &MOJOSHADER_out_of_mem_effect;  // supply both or neither.

    if (m == NULL) m = MOJOSHADER_internal_malloc;

    if (f == NULL) f = MOJOSHADER_internal_free;

    MOJOSHADER_effect *retval = m(sizeof (MOJOSHADER_effect), d);

    if (retval == NULL)

        return &MOJOSHADER_out_of_mem_effect;  // supply both or neither.

    memset(retval, '\0', sizeof (*retval));

    retval->malloc = m;

    retval->free = f;

    retval->malloc_data = d;

    const uint8 *ptr = (const uint8 *) buf;

    uint32 len = (uint32) _len;

    size_t siz = 0;

    int i, j, k;

    if (len < 8)

        goto parseEffect_unexpectedEOF;

    if (readui32(&ptr, &len) != 0xFEFF0901) // !!! FIXME: is this always magic?

        goto parseEffect_notAnEffectsFile;

    else

    {

        const uint32 offset = readui32(&ptr, &len);

        if (offset > len)

            goto parseEffect_unexpectedEOF;

        ptr += offset;

        len -= offset;

    } // else

    // params...

    if (len < 16)

        goto parseEffect_unexpectedEOF;

    const uint32 numparams = readui32(&ptr, &len);

    const uint32 numtechniques = readui32(&ptr, &len);

    readui32(&ptr, &len); // !!! FIXME: there are 8 unknown bytes here.

    readui32(&ptr, &len);

    for (i = 0; i < numparams; i++)

    {

        if (len < 16)

            goto parseEffect_unexpectedEOF;

        /*const uint32 startoffset = */ readui32(&ptr, &len);

        /*const uint32 endoffset = */ readui32(&ptr, &len);

        readui32(&ptr, &len);  // !!! FIXME: don't know what this is.

        const uint32 numannos = readui32(&ptr, &len);

        for (j = 0; j < numannos; j++)

        {

            if (len < 8)

                goto parseEffect_unexpectedEOF;

            // !!! FIXME: parse annotations.

            readui32(&ptr, &len);

            readui32(&ptr, &len);

        } // for

    } // for

    uint32 numshaders = 0;  // we'll calculate this later.

    // techniques...

    if (numtechniques > 0)

    {

        siz = sizeof (MOJOSHADER_effectTechnique) * numtechniques;

        retval->techniques = (MOJOSHADER_effectTechnique *) m(siz, d);

        if (retval->techniques == NULL)

            goto parseEffect_outOfMemory;

        memset(retval->techniques, '\0', siz);

        retval->technique_count = numtechniques;

        for (i = 0; i < numtechniques; i++)

        {

            if (len < 12)

                goto parseEffect_unexpectedEOF;

            MOJOSHADER_effectTechnique *technique = &retval->techniques[i];

            // !!! FIXME: is this always 12?

            const uint32 nameoffset = readui32(&ptr, &len) + 12;

            readui32(&ptr, &len);  // !!! FIXME: don't know what this field does.

            const uint32 numpasses = readui32(&ptr, &len);

            if (nameoffset >= _len)

                goto parseEffect_unexpectedEOF;

            if (numpasses > 0)

            {

                // !!! FIXME: verify this doesn't go past EOF looking for a null.

                siz = strlen(((const char *) buf) + nameoffset) + 1;

                technique->name = (char *) m(siz, d);

                if (technique->name == NULL)

                    goto parseEffect_outOfMemory;

                strcpy((char *) technique->name, ((const char *) buf) + nameoffset);

                technique->pass_count = numpasses;

                siz = sizeof (MOJOSHADER_effectPass) * numpasses;

                technique->passes = (MOJOSHADER_effectPass *) m(siz, d);

                if (technique->passes == NULL)

                    goto parseEffect_outOfMemory;

                memset(technique->passes, '\0', siz);

                for (j = 0; j < numpasses; j++)

                {

                    if (len < 12)

                        goto parseEffect_unexpectedEOF;

                    MOJOSHADER_effectPass *pass = &technique->passes[j];

                    // !!! FIXME: is this always 12?

                    const uint32 passnameoffset = readui32(&ptr, &len) + 12;

                    readui32(&ptr, &len);  // !!! FIXME: don't know what this field does.

                    const uint32 numstates = readui32(&ptr, &len);

                    if (passnameoffset >= _len)

                        goto parseEffect_unexpectedEOF;

                    // !!! FIXME: verify this doesn't go past EOF looking for a null.

                    siz = strlen(((const char *) buf) + passnameoffset) + 1;

                    pass->name = (char *) m(siz, d);

                    if (pass->name == NULL)

                        goto parseEffect_outOfMemory;

                    strcpy((char *) pass->name, ((const char *) buf) + passnameoffset);

                    if (numstates > 0)

                    {

                        pass->state_count = numstates;

                        siz = sizeof (MOJOSHADER_effectState) * numstates;

                        pass->states = (MOJOSHADER_effectState *) m(siz, d);

                        if (pass->states == NULL)

                            goto parseEffect_outOfMemory;

                        memset(pass->states, '\0', siz);

                        for (k = 0; k < numstates; k++)

                        {

                            if (len < 16)

                                goto parseEffect_unexpectedEOF;

                            MOJOSHADER_effectState *state = &pass->states[k];

                            const uint32 type = readui32(&ptr, &len);

                            readui32(&ptr, &len);  // !!! FIXME: don't know what this field does.

                            /*const uint32 offsetend = */ readui32(&ptr, &len);

                            /*const uint32 offsetstart = */ readui32(&ptr, &len);

                            state->type = type;

                            if ((type == 0x92) || (type == 0x93))

                                numshaders++;

                        } // for

                    } // if

                } // for

            } // if

        } // for

    } // if

    // textures...

    if (len < 8)

        goto parseEffect_unexpectedEOF;

    const int numtextures = readui32(&ptr, &len);

    const int numobjects = readui32(&ptr, &len);  // !!! FIXME: "objects" for lack of a better word.

    if (numtextures > 0)

    {

        siz = sizeof (MOJOSHADER_effectTexture) * numtextures;

        retval->textures = m(siz, d);

        if (retval->textures == NULL)

            goto parseEffect_outOfMemory;

        memset(retval->textures, '\0', siz);

        for (i = 0; i < numtextures; i++)

        {

            if (len < 8)

                goto parseEffect_unexpectedEOF;

            MOJOSHADER_effectTexture *texture = &retval->textures[i];

            const uint32 texparam = readui32(&ptr, &len);

            const uint32 texsize = readui32(&ptr, &len);

            // apparently texsize will pad out to 32 bits.

            const uint32 readsize = (((texsize + 3) / 4) * 4);

            if (len < readsize)

                goto parseEffect_unexpectedEOF;

            texture->param = texparam;

            char *str = m(texsize + 1, d);

            if (str == NULL)

                goto parseEffect_outOfMemory;

            memcpy(str, ptr, texsize);

            str[texsize] = '\0';

            texture->name = str;

            ptr += readsize;

            len -= readsize;

        } // for

    } // if

    // shaders...

    if (numshaders > 0)

    {

        siz = sizeof (MOJOSHADER_effectShader) * numshaders;

        retval->shaders = (MOJOSHADER_effectShader *) m(siz, d);

        if (retval->shaders == NULL)

            goto parseEffect_outOfMemory;

        memset(retval->shaders, '\0', siz);

        retval->shader_count = numshaders;

        // !!! FIXME: I wonder if we should pull these from offsets and not

        // !!! FIXME:  count on them all being in a line like this.

        for (i = 0; i < numshaders; i++)

        {

            if (len < 24)

                goto parseEffect_unexpectedEOF;

            MOJOSHADER_effectShader *shader = &retval->shaders[i];

            const uint32 technique = readui32(&ptr, &len);

            const uint32 pass = readui32(&ptr, &len);

            readui32(&ptr, &len);  // !!! FIXME: don't know what this does.

            readui32(&ptr, &len);  // !!! FIXME: don't know what this does (vertex/pixel/geometry?)

            readui32(&ptr, &len);  // !!! FIXME: don't know what this does.

            const uint32 shadersize = readui32(&ptr, &len);

            if (len < shadersize)

                goto parseEffect_unexpectedEOF;

            shader->technique = technique;

            shader->pass = pass;

            shader->shader = MOJOSHADER_parse(profile, ptr, shadersize,

                                              swiz, swizcount, m, f, d);

            // !!! FIXME: check for errors.

            ptr += shadersize;

            len -= shadersize;

        } // for

    } // if

    // !!! FIXME: we parse this, but don't expose the data, yet.

    // mappings ...

    assert(numshaders <= numobjects);

    const uint32 nummappings = numobjects - numshaders;

    if (nummappings > 0)

    {

        for (i = 0; i < nummappings; i++)

        {

            if (len < 24)

                goto parseEffect_unexpectedEOF;

            /*const uint32 magic = */ readui32(&ptr, &len);

            /*const uint32 index = */ readui32(&ptr, &len);

            readui32(&ptr, &len);  // !!! FIXME: what is this field?

            readui32(&ptr, &len);  // !!! FIXME: what is this field?

            /*const uint32 type = */ readui32(&ptr, &len);

            const uint32 mapsize = readui32(&ptr, &len);

            if (mapsize > 0)

            {

                const uint32 readsize = (((mapsize + 3) / 4) * 4);

                if (len < readsize)

                    goto parseEffect_unexpectedEOF;

            } // if

        } // for

    } // if

    retval->profile = (char *) m(strlen(profile) + 1, d);

    if (retval->profile == NULL)

        goto parseEffect_outOfMemory;

    strcpy((char *) retval->profile, profile);

    return retval;

// !!! FIXME: do something with this.

parseEffect_notAnEffectsFile:

parseEffect_unexpectedEOF:

parseEffect_outOfMemory:

    MOJOSHADER_freeEffect(retval);

    return &MOJOSHADER_out_of_mem_effect;

} // MOJOSHADER_parseEffect

void MOJOSHADER_freeEffect(const MOJOSHADER_effect *_effect)

{

    MOJOSHADER_effect *effect = (MOJOSHADER_effect *) _effect;

    if ((effect == NULL) || (effect == &MOJOSHADER_out_of_mem_effect))

        return;  // no-op.

    MOJOSHADER_free f = effect->free;

    void *d = effect->malloc_data;

    int i, j;

    for (i = 0; i < effect->error_count; i++)

    {

        f((void *) effect->errors[i].error, d);

        f((void *) effect->errors[i].filename, d);

    } // for

    f((void *) effect->errors, d);

    f((void *) effect->profile, d);

    for (i = 0; i < effect->technique_count; i++)

    {

        MOJOSHADER_effectTechnique *technique = &effect->techniques[i];

        for (j = 0; j < technique->pass_count; j++)

            f(technique->passes[j].states, d);

        f(technique->passes, d);

    } // for

    f(effect->techniques, d);

    for (i = 0; i < effect->texture_count; i++)

        f((void *) effect->textures[i].name, d);

    f(effect->textures, d);

    for (i = 0; i < effect->shader_count; i++)

        MOJOSHADER_freeParseData(effect->shaders[i].shader);

    f(effect->shaders, d);

    f(effect, d);

} // MOJOSHADER_freeEffect

// end of mojoshader_effects.c ...