/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "GLClientState.h"
#include "ErrorLog.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "glUtils.h"
#include <cutils/log.h>

#ifndef MAX
#define MAX(a, b) ((a) < (b) ? (b) : (a))
#endif

GLClientState::GLClientState(int nLocations)
{
    if (nLocations < LAST_LOCATION) {
        nLocations = LAST_LOCATION;
    }
    m_nLocations = nLocations;
    m_states = new VertexAttribState[m_nLocations];
    for (int i = 0; i < m_nLocations; i++) {
        m_states[i].enabled = 0;
        m_states[i].enableDirty = false;
        m_states[i].data = 0;
    }
    m_currentArrayVbo = 0;
    m_currentIndexVbo = 0;
    // init gl constans;
    m_states[VERTEX_LOCATION].glConst = GL_VERTEX_ARRAY;
    m_states[NORMAL_LOCATION].glConst = GL_NORMAL_ARRAY;
    m_states[COLOR_LOCATION].glConst = GL_COLOR_ARRAY;
    m_states[POINTSIZE_LOCATION].glConst = GL_POINT_SIZE_ARRAY_OES;
    m_states[TEXCOORD0_LOCATION].glConst = GL_TEXTURE_COORD_ARRAY;
    m_states[TEXCOORD1_LOCATION].glConst = GL_TEXTURE_COORD_ARRAY;
    m_states[TEXCOORD2_LOCATION].glConst = GL_TEXTURE_COORD_ARRAY;
    m_states[TEXCOORD3_LOCATION].glConst = GL_TEXTURE_COORD_ARRAY;
    m_states[TEXCOORD4_LOCATION].glConst = GL_TEXTURE_COORD_ARRAY;
    m_states[TEXCOORD5_LOCATION].glConst = GL_TEXTURE_COORD_ARRAY;
    m_states[TEXCOORD6_LOCATION].glConst = GL_TEXTURE_COORD_ARRAY;
    m_states[TEXCOORD7_LOCATION].glConst = GL_TEXTURE_COORD_ARRAY;
    m_states[MATRIXINDEX_LOCATION].glConst = GL_MATRIX_INDEX_ARRAY_OES;
    m_states[WEIGHT_LOCATION].glConst = GL_WEIGHT_ARRAY_OES;
    m_activeTexture = 0;
    m_currentProgram = 0;

    m_pixelStore.unpack_alignment = 4;
    m_pixelStore.pack_alignment = 4;

    memset(m_tex.unit, 0, sizeof(m_tex.unit));
    m_tex.activeUnit = &m_tex.unit[0];
    m_tex.textures = NULL;
    m_tex.numTextures = 0;
    m_tex.allocTextures = 0;
}

GLClientState::~GLClientState()
{
    delete m_states;
}

void GLClientState::enable(int location, int state)
{
    if (!validLocation(location)) {
        return;
    }

    m_states[location].enableDirty |= (state != m_states[location].enabled);
    m_states[location].enabled = state;
}

void GLClientState::setState(int location, int size, GLenum type, GLboolean normalized, GLsizei stride, const void *data)
{
    if (!validLocation(location)) {
        return;
    }
    m_states[location].size = size;
    m_states[location].type = type;
    m_states[location].stride = stride;
    m_states[location].data = (void*)data;
    m_states[location].bufferObject = m_currentArrayVbo;
    m_states[location].elementSize = size ? (glSizeof(type) * size) : 0;
    m_states[location].normalized = normalized;
}

void GLClientState::setBufferObject(int location, GLuint id)
{
    if (!validLocation(location)) {
        return;
    }

    m_states[location].bufferObject = id;
}

const GLClientState::VertexAttribState * GLClientState::getState(int location)
{
    if (!validLocation(location)) {
        return NULL;
    }
    return & m_states[location];
}

const GLClientState::VertexAttribState * GLClientState::getStateAndEnableDirty(int location, bool *enableChanged)
{
    if (!validLocation(location)) {
        return NULL;
    }

    if (enableChanged) {
        *enableChanged = m_states[location].enableDirty;
    }

    m_states[location].enableDirty = false;
    return & m_states[location];
}

int GLClientState::getLocation(GLenum loc)
{
    int retval;

    switch(loc) {
    case GL_VERTEX_ARRAY:
        retval = int(VERTEX_LOCATION);
        break;
    case GL_NORMAL_ARRAY:
        retval = int(NORMAL_LOCATION);
        break;
    case GL_COLOR_ARRAY:
        retval = int(COLOR_LOCATION);
        break;
    case GL_POINT_SIZE_ARRAY_OES:
        retval = int(POINTSIZE_LOCATION);
        break;
    case GL_TEXTURE_COORD_ARRAY:
        retval = int (TEXCOORD0_LOCATION + m_activeTexture);
        break;
    case GL_MATRIX_INDEX_ARRAY_OES:
        retval = int (MATRIXINDEX_LOCATION);
        break;
    case GL_WEIGHT_ARRAY_OES:
        retval = int (WEIGHT_LOCATION);
        break;
    default:
        retval = loc;
    }
    return retval;
}

void GLClientState::getClientStatePointer(GLenum pname, GLvoid** params)
{
    const GLClientState::VertexAttribState *state = NULL;
    switch (pname) {
    case GL_VERTEX_ARRAY_POINTER: {
        state = getState(GLClientState::VERTEX_LOCATION);
        break;
        }
    case GL_NORMAL_ARRAY_POINTER: {
        state = getState(GLClientState::NORMAL_LOCATION);
        break;
        }
    case GL_COLOR_ARRAY_POINTER: {
        state = getState(GLClientState::COLOR_LOCATION);
        break;
        }
    case GL_TEXTURE_COORD_ARRAY_POINTER: {
        state = getState(getActiveTexture() + GLClientState::TEXCOORD0_LOCATION);
        break;
        }
    case GL_POINT_SIZE_ARRAY_POINTER_OES: {
        state = getState(GLClientState::POINTSIZE_LOCATION);
        break;
        }
    case GL_MATRIX_INDEX_ARRAY_POINTER_OES: {
        state = getState(GLClientState::MATRIXINDEX_LOCATION);
        break;
        }
    case GL_WEIGHT_ARRAY_POINTER_OES: {
        state = getState(GLClientState::WEIGHT_LOCATION);
        break;
        }
    }
    if (state && params)
        *params = state->data;
}

int GLClientState::setPixelStore(GLenum param, GLint value)
{
    int retval = 0;
    switch(param) {
    case GL_UNPACK_ALIGNMENT:
        if (value == 1 || value == 2 || value == 4 || value == 8) {
            m_pixelStore.unpack_alignment = value;
        } else {
            retval =  GL_INVALID_VALUE;
        }
        break;
    case GL_PACK_ALIGNMENT:
        if (value == 1 || value == 2 || value == 4 || value == 8) {
            m_pixelStore.pack_alignment = value;
        } else {
            retval =  GL_INVALID_VALUE;
        }
        break;
        default:
            retval = GL_INVALID_ENUM;
    }
    return retval;
}


size_t GLClientState::pixelDataSize(GLsizei width, GLsizei height, GLenum format, GLenum type, int pack) const
{
    if (width <= 0 || height <= 0) return 0;

    int pixelsize = glUtilsPixelBitSize(format, type) >> 3;

    int alignment = pack ? m_pixelStore.pack_alignment : m_pixelStore.unpack_alignment;

    if (pixelsize == 0 ) {
        ERR("unknown pixel size: width: %d height: %d format: %d type: %d pack: %d align: %d\n",
             width, height, format, type, pack, alignment);
    }
    size_t linesize = pixelsize * width;
    size_t aligned_linesize = int(linesize / alignment) * alignment;
    if (aligned_linesize < linesize) {
        aligned_linesize += alignment;
    }
    return aligned_linesize * height;
}

GLenum GLClientState::setActiveTextureUnit(GLenum texture)
{
    GLuint unit = texture - GL_TEXTURE0;
    if (unit >= MAX_TEXTURE_UNITS) {
        return GL_INVALID_ENUM;
    }
    m_tex.activeUnit = &m_tex.unit[unit];
    return GL_NO_ERROR;
}

GLenum GLClientState::getActiveTextureUnit() const
{
    return GL_TEXTURE0 + (m_tex.activeUnit - &m_tex.unit[0]);
}

void GLClientState::enableTextureTarget(GLenum target)
{
    switch (target) {
    case GL_TEXTURE_2D:
        m_tex.activeUnit->enables |= (1u << TEXTURE_2D);
        break;
    case GL_TEXTURE_EXTERNAL_OES:
        m_tex.activeUnit->enables |= (1u << TEXTURE_EXTERNAL);
        break;
    }
}

void GLClientState::disableTextureTarget(GLenum target)
{
    switch (target) {
    case GL_TEXTURE_2D:
        m_tex.activeUnit->enables &= ~(1u << TEXTURE_2D);
        break;
    case GL_TEXTURE_EXTERNAL_OES:
        m_tex.activeUnit->enables &= ~(1u << TEXTURE_EXTERNAL);
        break;
    }
}

GLenum GLClientState::getPriorityEnabledTarget(GLenum allDisabled) const
{
    unsigned int enables = m_tex.activeUnit->enables;
    if (enables & (1u << TEXTURE_EXTERNAL)) {
        return GL_TEXTURE_EXTERNAL_OES;
    } else if (enables & (1u << TEXTURE_2D)) {
        return GL_TEXTURE_2D;
    } else {
        return allDisabled;
    }
}

int GLClientState::compareTexId(const void* pid, const void* prec)
{
    const GLuint* id = (const GLuint*)pid;
    const TextureRec* rec = (const TextureRec*)prec;
    return (GLint)(*id) - (GLint)rec->id;
}

GLenum GLClientState::bindTexture(GLenum target, GLuint texture,
        GLboolean* firstUse)
{
    GLboolean first = GL_FALSE;
    TextureRec* texrec = NULL;
    if (texture != 0) {
        if (m_tex.textures) {
            texrec = (TextureRec*)bsearch(&texture, m_tex.textures,
                    m_tex.numTextures, sizeof(TextureRec), compareTexId);
        }
        if (!texrec) {
            if (!(texrec = addTextureRec(texture, target))) {
                return GL_OUT_OF_MEMORY;
            }
            first = GL_TRUE;
        }
        if (target != texrec->target) {
            return GL_INVALID_OPERATION;
        }
    }

    switch (target) {
    case GL_TEXTURE_2D:
        m_tex.activeUnit->texture[TEXTURE_2D] = texture;
        break;
    case GL_TEXTURE_EXTERNAL_OES:
        m_tex.activeUnit->texture[TEXTURE_EXTERNAL] = texture;
        break;
    }

    if (firstUse) {
        *firstUse = first;
    }

    return GL_NO_ERROR;
}

GLClientState::TextureRec* GLClientState::addTextureRec(GLuint id,
        GLenum target)
{
    if (m_tex.numTextures == m_tex.allocTextures) {
        const GLuint MAX_TEXTURES = 0xFFFFFFFFu;

        GLuint newAlloc;
        if (MAX_TEXTURES - m_tex.allocTextures >= m_tex.allocTextures) {
            newAlloc = MAX(4, 2 * m_tex.allocTextures);
        } else {
            if (m_tex.allocTextures == MAX_TEXTURES) {
                return NULL;
            }
            newAlloc = MAX_TEXTURES;
        }

        TextureRec* newTextures = (TextureRec*)realloc(m_tex.textures,
                newAlloc * sizeof(TextureRec));
        if (!newTextures) {
            return NULL;
        }

        m_tex.textures = newTextures;
        m_tex.allocTextures = newAlloc;
    }

    TextureRec* tex = m_tex.textures + m_tex.numTextures;
    TextureRec* prev = tex - 1;
    while (tex != m_tex.textures && id < prev->id) {
        *tex-- = *prev--;
    }
    tex->id = id;
    tex->target = target;
    m_tex.numTextures++;

    return tex;
}

GLuint GLClientState::getBoundTexture(GLenum target) const
{
    switch (target) {
    case GL_TEXTURE_2D:
        return m_tex.activeUnit->texture[TEXTURE_2D];
    case GL_TEXTURE_EXTERNAL_OES:
        return m_tex.activeUnit->texture[TEXTURE_EXTERNAL];
    default:
        return 0;
    }
}

void GLClientState::deleteTextures(GLsizei n, const GLuint* textures)
{
    // Updating the textures array could be made more efficient when deleting
    // several textures:
    // - compacting the array could be done in a single pass once the deleted
    //   textures are marked, or
    // - could swap deleted textures to the end and re-sort.
    TextureRec* texrec;
    for (const GLuint* texture = textures; texture != textures + n; texture++) {
        texrec = (TextureRec*)bsearch(texture, m_tex.textures,
                m_tex.numTextures, sizeof(TextureRec), compareTexId);
        if (texrec) {
            const TextureRec* end = m_tex.textures + m_tex.numTextures;
            memmove(texrec, texrec + 1,
                    (end - texrec - 1) * sizeof(TextureRec));
            m_tex.numTextures--;

            for (TextureUnit* unit = m_tex.unit;
                 unit != m_tex.unit + MAX_TEXTURE_UNITS;
                 unit++)
            {
                if (unit->texture[TEXTURE_2D] == *texture) {
                    unit->texture[TEXTURE_2D] = 0;
                } else if (unit->texture[TEXTURE_EXTERNAL] == *texture) {
                    unit->texture[TEXTURE_EXTERNAL] = 0;
                }
            }
        }
    }
}