/*
 * Copyright (C) 2009 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 "rsContext.h"
#include "rsProgramVertex.h"

#include <GLES/gl.h>
#include <GLES/glext.h>

using namespace android;
using namespace android::renderscript;


ProgramVertex::ProgramVertex(Context *rsc, Element *in, Element *out) :
    Program(rsc, in, out)
{
    mAllocFile = __FILE__;
    mAllocLine = __LINE__;
    mTextureMatrixEnable = false;
    mLightCount = 0;
}

ProgramVertex::~ProgramVertex()
{
}

static void logMatrix(const char *txt, const float *f)
{
    LOGV("Matrix %s, %p", txt, f);
    LOGV("%6.2f, %6.2f, %6.2f, %6.2f", f[0], f[4], f[8], f[12]);
    LOGV("%6.2f, %6.2f, %6.2f, %6.2f", f[1], f[5], f[9], f[13]);
    LOGV("%6.2f, %6.2f, %6.2f, %6.2f", f[2], f[6], f[10], f[14]);
    LOGV("%6.2f, %6.2f, %6.2f, %6.2f", f[3], f[7], f[11], f[15]);
}

void ProgramVertex::setupGL(const Context *rsc, ProgramVertexState *state)
{
    if ((state->mLast.get() == this) && !mDirty) {
        return;
    }
    state->mLast.set(this);

    const float *f = static_cast<const float *>(mConstants->getPtr());

    glMatrixMode(GL_TEXTURE);
    if (mTextureMatrixEnable) {
        glLoadMatrixf(&f[RS_PROGRAM_VERTEX_TEXTURE_OFFSET]);
    } else {
        glLoadIdentity();
    }

    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    if (mLightCount) {
        int v = 0;
        glEnable(GL_LIGHTING);
        glLightModelxv(GL_LIGHT_MODEL_TWO_SIDE, &v);
        for (uint32_t ct = 0; ct < mLightCount; ct++) {
            const Light *l = mLights[ct].get();
            glEnable(GL_LIGHT0 + ct);
            l->setupGL(ct);
        }
        for (uint32_t ct = mLightCount; ct < MAX_LIGHTS; ct++) {
            glDisable(GL_LIGHT0 + ct);
        }
    } else {
        glDisable(GL_LIGHTING);
    }

    if (!f) {
        LOGE("Must bind constants to vertex program");
    }

    glMatrixMode(GL_PROJECTION);
    glLoadMatrixf(&f[RS_PROGRAM_VERTEX_PROJECTION_OFFSET]);
    glMatrixMode(GL_MODELVIEW);
    glLoadMatrixf(&f[RS_PROGRAM_VERTEX_MODELVIEW_OFFSET]);

    mDirty = false;
}

void ProgramVertex::addLight(const Light *l)
{
    if (mLightCount < MAX_LIGHTS) {
        mLights[mLightCount].set(l);
        mLightCount++;
    }
}

void ProgramVertex::setProjectionMatrix(const rsc_Matrix *m) const
{
    float *f = static_cast<float *>(mConstants->getPtr());
    memcpy(&f[RS_PROGRAM_VERTEX_PROJECTION_OFFSET], m, sizeof(rsc_Matrix));
    mDirty = true;
}

void ProgramVertex::setModelviewMatrix(const rsc_Matrix *m) const
{
    float *f = static_cast<float *>(mConstants->getPtr());
    memcpy(&f[RS_PROGRAM_VERTEX_MODELVIEW_OFFSET], m, sizeof(rsc_Matrix));
    mDirty = true;
}

void ProgramVertex::setTextureMatrix(const rsc_Matrix *m) const
{
    float *f = static_cast<float *>(mConstants->getPtr());
    memcpy(&f[RS_PROGRAM_VERTEX_TEXTURE_OFFSET], m, sizeof(rsc_Matrix));
    mDirty = true;
}

void ProgramVertex::transformToScreen(const Context *rsc, float *v4out, const float *v3in) const
{
    float *f = static_cast<float *>(mConstants->getPtr());
    Matrix mvp;
    mvp.loadMultiply((Matrix *)&f[RS_PROGRAM_VERTEX_MODELVIEW_OFFSET],
                     (Matrix *)&f[RS_PROGRAM_VERTEX_PROJECTION_OFFSET]);
    mvp.vectorMultiply(v4out, v3in);
}

ProgramVertexState::ProgramVertexState()
{
    mPV = NULL;
}

ProgramVertexState::~ProgramVertexState()
{
    delete mPV;
}

void ProgramVertexState::init(Context *rsc, int32_t w, int32_t h)
{
    rsi_ElementBegin(rsc);
    rsi_ElementAdd(rsc, RS_KIND_USER, RS_TYPE_FLOAT, false, 32, NULL);
    RsElement e = rsi_ElementCreate(rsc);

    rsi_TypeBegin(rsc, e);
    rsi_TypeAdd(rsc, RS_DIMENSION_X, 48);
    mAllocType.set((Type *)rsi_TypeCreate(rsc));

    ProgramVertex *pv = new ProgramVertex(rsc, NULL, NULL);
    Allocation *alloc = (Allocation *)rsi_AllocationCreateTyped(rsc, mAllocType.get());
    mDefaultAlloc.set(alloc);
    mDefault.set(pv);

    pv->bindAllocation(alloc);

    Matrix m;
    m.loadOrtho(0,w, h,0, -1,1);
    alloc->subData(RS_PROGRAM_VERTEX_PROJECTION_OFFSET, 16, &m.m[0], 16*4);

    m.loadIdentity();
    alloc->subData(RS_PROGRAM_VERTEX_MODELVIEW_OFFSET, 16, &m.m[0], 16*4);
}

void ProgramVertexState::deinit(Context *rsc)
{
    mDefaultAlloc.clear();
    mDefault.clear();
    mAllocType.clear();
    mLast.clear();
    delete mPV;
    mPV = NULL;
}


namespace android {
namespace renderscript {

void rsi_ProgramVertexBegin(Context *rsc, RsElement in, RsElement out)
{
    delete rsc->mStateVertex.mPV;
    rsc->mStateVertex.mPV = new ProgramVertex(rsc, (Element *)in, (Element *)out);
}

RsProgramVertex rsi_ProgramVertexCreate(Context *rsc)
{
    ProgramVertex *pv = rsc->mStateVertex.mPV;
    pv->incUserRef();
    rsc->mStateVertex.mPV = 0;
    return pv;
}

void rsi_ProgramVertexBindAllocation(Context *rsc, RsProgramVertex vpgm, RsAllocation constants)
{
    ProgramVertex *pv = static_cast<ProgramVertex *>(vpgm);
    pv->bindAllocation(static_cast<Allocation *>(constants));
}

void rsi_ProgramVertexSetTextureMatrixEnable(Context *rsc, bool enable)
{
    rsc->mStateVertex.mPV->setTextureMatrixEnable(enable);
}

void rsi_ProgramVertexAddLight(Context *rsc, RsLight light)
{
    rsc->mStateVertex.mPV->addLight(static_cast<const Light *>(light));
}


}
}