/*---------------------------------------------------------------------------*
  Project:  Horizon
  File:     gx_CommandCacheVSUniformFrame.cpp

  Copyright (C)2009-2012 Nintendo Co., Ltd.  All rights reserved.

  These coded instructions, statements, and computer programs contain
  proprietary information of Nintendo of America Inc. and/or Nintendo
  Company Ltd., and are protected by Federal copyright law.  They may
  not be disclosed to third parties or copied or duplicated in any form,
  in whole or in part, without the prior written consent of Nintendo.

  $Rev: 47228 $
 *---------------------------------------------------------------------------*/

#include <nn/os.h>
#include <nn/fnd.h>
#include <nn/gx.h>
#include <nn/math.h>
#include <nn/fs.h>
#include <nn/init.h>
#include <nn/applet.h>

#include "demo.h"

// Save the command list and reuse it.
#define USE_COMMAND_CACHE

namespace
{        
    u32 s_CommandListSize = 0x10000;
    u32 s_CommandListRequestNum = 64;
    GLbitfield s_StateMask = 0;

    // Number of models to render
    const u32 MAX_MODEL_NUM = 50;

    // Copies the 3D command buffer.
    GLboolean s_CopyCommandBuffer = GL_TRUE;
    // References the 3D command buffer.
    // GLboolean s_CopyCommandBuffer = GL_FALSE;

    // Index of the array that stores the offset to the model view matrix.
    const u32 s_ModelViewArrayIndex = 0;
    // Start index of the floating point register of the model view matrix (ModelView c4-c7) in the vertex shader    
    const u32 s_ModelViewRegIndex = 4;

    // Renders multiple models in a single command cache.
    demo::CommandCache s_CommandCache;

    GLuint s_ProgramId = 0;
    GLuint s_ShaderId = 0;
        
    nn::fnd::ExpHeap s_AppHeap;
    uptr s_AddrForGxHeap;
    const u32 s_GxHeapSize = 0x800000;
        
    demo::RenderSystem s_RenderSystem;

    nn::math::Vector3 s_CameraPosition(0.0f, 4.0f, 6.0f);
    nn::math::Vector3 s_CameraUp(0.0f, 1.0f, 0.0f);
    nn::math::Vector3 s_CameraTarget(0.0f, 0.0f, 0.0f);

    nn::math::Matrix34 s_ViewMatrix;
    nn::math::Matrix44 s_Display0ProjectionMatrix;
    nn::math::Matrix44 s_Display1ProjectionMatrix;
    
    f32 s_GlobalAmbientLight[] = { 0.3f,  0.3f,  0.3f, 1.0f};
    f32 s_Light0Ambient[]      = { 0.3f,  0.3f,  0.3f, 1.0f};
    f32 s_Light0Diffuse[]      = { 0.7f,  0.7f,  0.7f, 1.0f};
    f32 s_Light0Position[]     = {15.0f, 15.0f, 15.0f, 1.0f};

    f32 s_MaterialAmbient[] = {0.3f, 0.3f, 0.3f, 1.0f};    
    f32 s_MaterialDiffuse[] = {0.7f, 0.7f, 0.7f, 1.0f};

    const nn::math::Vector3 s_InitialPosition(0.0f, -3.0f, 0.0f);
    const nn::math::Vector3 s_InitialVelocity(0.0f, 1.0f, 0.0f);
    const nn::math::Vector3 s_Gravity(0.0f, -0.1f, 0.0f);

    const f32 s_DeltaTime = 0.1f;    
    demo::Particle s_ParticleArray[MAX_MODEL_NUM];
    
    const f32 s_ParticleRadius = 0.4f;
    const u32 s_ParticleDivision = 4;
}

void Initialize(void);
void InitializeGraphics(void);
void InitializeCommandCache(void);
void InitializeShader(void);

void Finalize(void);

// If using normal rendering
bool DrawFrame(void);
void SetDisplay0ProjectionMatrix(void);
void UseShader(void);
void UpdateCamera(void);
void DrawDisplay0(void);
void DrawDisplay1(void);
void UpdateBody(demo::Body& body);
void DrawBody(demo::Body& body);

// If using the command cache to render
bool DrawFrameCommandCache(void);
void MakeDisplay0CommandCache(void);
void DrawDisplay0CommandCache(void);
void UpdateDisplay0CommandCache(void);

void Initialize(void)
{
    // fs initialization
    nn::fs::Initialize();

    const size_t ROMFS_BUFFER_SIZE = 1024 * 64;
    static char buffer[ROMFS_BUFFER_SIZE];
    NN_UTIL_PANIC_IF_FAILED(
        nn::fs::MountRom(16, 16, buffer, ROMFS_BUFFER_SIZE));
    
    InitializeGraphics();
}

void InitializeGraphics(void)
{
    s_AppHeap.Initialize(nn::os::GetDeviceMemoryAddress(), 
        nn::os::GetDeviceMemorySize() );
    s_AddrForGxHeap = reinterpret_cast<uptr>(s_AppHeap.Allocate(s_GxHeapSize));

    s_RenderSystem.Initialize(s_AddrForGxHeap, s_GxHeapSize);    

    // Stops executing the command list.    
    nngxStopCmdlist();

    glClearColor(0.3f, 0.3f, 0.3f, 1.0f);
    glClearDepthf(1.f);

    glEnable(GL_DEPTH_TEST);
    glDepthFunc(GL_LESS);

    glEnable(GL_CULL_FACE);    
    glFrontFace(GL_CCW);
    glCullFace(GL_BACK);
    
    InitializeShader();
    
    // Initialize projection matrix
    nn::math::MTX44PerspectivePivotDeg(&s_Display0ProjectionMatrix, 45.0f, 
        demo::DISPLAY0_ASPECT, 0.2f, 100.0f,
        nn::math::PIVOT_UPSIDE_TO_TOP);

    nn::math::MTX44PerspectivePivotDeg(&s_Display1ProjectionMatrix, 45.0f, 
        demo::DISPLAY1_ASPECT, 0.2f, 100.0f,
        nn::math::PIVOT_UPSIDE_TO_TOP);

    u32 vertexAttributes = demo::VERTEX_POSITION_ATTRIBUTE | 
        demo::VERTEX_COLOR_ATTRIBUTE | 
        demo::VERTEX_NORMAL_ATTRIBUTE;    

    demo::Particle::s_InitialPosition = ::s_InitialPosition;
    demo::Particle::s_InitialVelocity = ::s_InitialVelocity;
    demo::Particle::s_Gravity = ::s_Gravity;

    NN_LOG("  ParticleRadius = %f\n", s_ParticleRadius);

    for (u32 modelIndex = 0; modelIndex < MAX_MODEL_NUM; modelIndex++)
    {
        s_ParticleArray[modelIndex].InitializeParticle(vertexAttributes, s_ParticleRadius, s_ParticleDivision);
    }
    NN_LOG("  ParticleVerticesNum = %d\n", s_ParticleArray[0].m_Sphere.GetPackedVerticesNum());
    NN_LOG("  ParticleTrianglesNum = %d\n", s_ParticleArray[0].m_Sphere.GetPackedTrianglesNum());

#ifdef USE_COMMAND_CACHE
    InitializeCommandCache();
#else
    NN_LOG("Normal mode (No command cache)\n");
#endif
}

void InitializeShader(void)
{    
    s_ProgramId = glCreateProgram();
    
    // Load vertex shader
    s_ShaderId = glCreateShader(GL_VERTEX_SHADER);
    nn::fs::FileReader file(L"rom:/shader.shbin");
    size_t fileSize = file.GetSize();
    void* buf = s_AppHeap.Allocate(fileSize);
    s32 read = file.Read(buf, fileSize);
    glShaderBinary(1, &s_ShaderId, GL_PLATFORM_BINARY_DMP, buf, read);
    file.Finalize();
    s_AppHeap.Free(buf);
    
    glAttachShader(s_ProgramId, s_ShaderId);
    glAttachShader(s_ProgramId, GL_DMP_FRAGMENT_SHADER_DMP);

    glBindAttribLocation(s_ProgramId, 0, "aPosition");    
    glBindAttribLocation(s_ProgramId, 1, "aColor");
    glBindAttribLocation(s_ProgramId, 2, "aNormal");

    glLinkProgram(s_ProgramId);
    glValidateProgram(s_ProgramId);

    demo::InitializeUniforms(s_ProgramId);    
}

void InitializeCommandCache(void)
{
    if ( s_CopyCommandBuffer )
    {
        NN_LOG("Command cache mode (COPY 3D command buffer)\n");
    }
    else
    {
        NN_LOG("Command cache mode (REFERENCE 3D command buffer)\n");        
    }

    // Initializes the command cache.
    s_CommandCache.Initialize(s_CommandListSize, s_CommandListRequestNum,    
            s_CopyCommandBuffer, s_StateMask, MAX_MODEL_NUM);

    for (u32 modelIndex = 0; modelIndex < MAX_MODEL_NUM; modelIndex++)
    {
        s_CommandCache.SetVSUniformMatrixRegisterIndex(modelIndex, s_ModelViewArrayIndex, s_ModelViewRegIndex);
    }        
}

void Finalize(void)
{       
#ifdef USE_COMMAND_CACHE
    s_CommandCache.Finalize();
#endif
    
    for (u32 modelIndex = 0; modelIndex < MAX_MODEL_NUM; modelIndex++)
    {
        s_ParticleArray[modelIndex].Finalize();
    }
        
    s_RenderSystem.Finalize();
    
    s_AppHeap.Free(reinterpret_cast<void*>(s_AddrForGxHeap));
    s_AppHeap.Finalize();
}

bool DrawFrame(void)
{                      
    UpdateCamera();
    DrawDisplay0();
    DrawDisplay1();

    s_RenderSystem.WaitVsync(NN_GX_DISPLAY_BOTH);    

    return true;
}

void DrawDisplay0(void)
{           
    s_RenderSystem.SetRenderTarget(NN_GX_DISPLAY0);
    s_RenderSystem.Clear();
    
    UseShader();
    SetDisplay0ProjectionMatrix();

    for (u32 modelIndex = 0; modelIndex < MAX_MODEL_NUM; modelIndex++)
    {                
        s_ParticleArray[modelIndex].Update(s_DeltaTime);
        DrawBody(s_ParticleArray[modelIndex]);
    }
    
    s_RenderSystem.SwapBuffers();    
}

void DrawDisplay1(void)
{    
    s_RenderSystem.SetRenderTarget(NN_GX_DISPLAY1);
    s_RenderSystem.Clear();
 
    s_RenderSystem.SwapBuffers(); 
}

void SetDisplay0ProjectionMatrix(void)
{
    glUniformMatrix4fv(demo::s_UniformLocations[demo::VERTEX_UNIFORM_PROJECTION], 
        1, GL_TRUE, static_cast<f32*>(s_Display0ProjectionMatrix));
}

void UseShader(void)
{ 
    glUseProgram(s_ProgramId);
                        
    // Fragment uniform
    glUniform1i(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_ALPHA_TEST], GL_FALSE);

    // Fragment uniform : Texture samplerType
    glUniform1i(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_TEXTURE0_SAMPLER_TYPE], GL_FALSE);
    glUniform1i(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_TEXTURE1_SAMPLER_TYPE], GL_FALSE);
    glUniform1i(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_TEXTURE2_SAMPLER_TYPE], GL_FALSE);
    glUniform1i(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_TEXTURE3_SAMPLER_TYPE], GL_FALSE);

    // Fragment uniform : Fragment lighting
    glUniform1i(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_FRAGMENT_LIGHTING_ENABLED], GL_TRUE);           
    glUniform4fv(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_FRAGMENT_LIGHTING_AMBIENT], 1, s_GlobalAmbientLight);    
    glUniform1i(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_FRAGMENT_LIGHT_SOURCE0_ENABLED], GL_TRUE);    
    glUniform4fv(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_FRAGMENT_LIGHT_SOURCE0_AMBIENT], 1, s_Light0Ambient);
    glUniform4fv(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_FRAGMENT_LIGHT_SOURCE0_DIFFUSE], 1, s_Light0Diffuse);
    glUniform4fv(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_FRAGMENT_LIGHT_SOURCE0_POSITION], 1, s_Light0Position);
        
    // Fragment uniform : Material
    glUniform4fv(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_FRAGMENT_MATERIAL_AMBIENT], 1, s_MaterialAmbient);
    glUniform4fv(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_FRAGMENT_MATERIAL_DIFFUSE], 1, s_MaterialDiffuse);
        
    // Fragment uniform : Texture combiner
    //   Modulate fragment primary color and vertex color.
    glUniform3i(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_TEXENV2_SRC_RGB],
        GL_FRAGMENT_PRIMARY_COLOR_DMP, GL_PRIMARY_COLOR, GL_PREVIOUS);        
    glUniform3i(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_TEXENV2_SRC_ALPHA],
        GL_PRIMARY_COLOR, GL_PRIMARY_COLOR, GL_PREVIOUS);        
    glUniform3i(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_TEXENV2_OPERAND_RGB],
        GL_SRC_COLOR, GL_SRC_COLOR, GL_SRC_COLOR);        
    glUniform3i(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_TEXENV2_OPERAND_ALPHA],
        GL_SRC_ALPHA, GL_SRC_ALPHA, GL_SRC_ALPHA);
    glUniform1i(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_TEXENV2_COMBINE_RGB], 
        GL_MODULATE);
    glUniform1i(demo::s_UniformLocations[demo::FRAGMENT_UNIFORM_TEXENV2_COMBINE_ALPHA], 
        GL_MODULATE);
}

void UpdateCamera(void)
{    
    nn::math::MTX34LookAt(&s_ViewMatrix, &s_CameraPosition, &s_CameraUp, &s_CameraTarget);        
}

void DrawBody(demo::Body& body)
{      
    nn::math::MTX44 modelViewMatrix(s_ViewMatrix);
    nn::math::Matrix44 worldMatrix = body.GetWorldMatrix();
    nn::math::MTX44Mult(&modelViewMatrix, &modelViewMatrix, &worldMatrix);    
    glUniformMatrix4fv(demo::s_UniformLocations[demo::VERTEX_UNIFORM_MODELVIEW],
        1, GL_TRUE, static_cast<f32*>(modelViewMatrix));
    
    body.Draw();
}

bool DrawFrameCommandCache(void)
{
    static bool s_InitializeCommandCache = false;    
    if (! s_InitializeCommandCache )
    {                
        UpdateCamera();
        MakeDisplay0CommandCache();
        
        DrawDisplay1();        
        s_InitializeCommandCache = true;
    }
    else
    {        
        UpdateCamera();
        DrawDisplay0CommandCache();
        DrawDisplay1();

        static bool firstFlag = true;
        if ( firstFlag )
        {
            s_CommandCache.Print();
            firstFlag = false;
        }
    }

    s_RenderSystem.WaitVsync(NN_GX_DISPLAY_BOTH);
    
    return true;
}

void MakeDisplay0CommandCache(void)
{       
    s_RenderSystem.SetRenderTarget(NN_GX_DISPLAY0);
    s_RenderSystem.Clear();

    // Starts saving the command list.
    s_CommandCache.BeginSave();
         
    UpdateCamera();
    UseShader();
    SetDisplay0ProjectionMatrix();

    for (u32 modelIndex = 0; modelIndex < MAX_MODEL_NUM; modelIndex++)
    {                
        s_ParticleArray[modelIndex].Update(s_DeltaTime);
        
        // Saves the offset to the start of the 3D command buffer when rendering one model
        //
        // This demo performs register write operations that update the vertex shader's model view matrices in the 3D command buffer of the command list. The number of writes is equal to MAX_MODEL_NUM.
        // 
        // 
        // To determine which model (specified by modelIndex) in the 3D command buffer should have its model view matrix overwritten, the demo saves the offset of the 3D command buffer before rendering the model.
        // 
        // When the demo overwrites the 3D command buffer, it uses the saved offset as a starting point to search for the first register write operation that overwrites the modelview matrix, and then overwrites it.
        // 
        s_CommandCache.SaveCommandBufferStartOffset(modelIndex);

        DrawBody(s_ParticleArray[modelIndex]);
    }
        
    // Ends saving the command list.
    s_CommandCache.EndSave();

    s_RenderSystem.SwapBuffers();        
}

// Reuses the saved command list.
void DrawDisplay0CommandCache(void)
{   
    s_RenderSystem.SetRenderTarget(NN_GX_DISPLAY0);
    s_RenderSystem.Clear();

    // Modifies the values of the model view matrix in the saved command list.
    UpdateDisplay0CommandCache();
    
    // Adds the saved command list to the current command list.
    s_CommandCache.Append();

    s_RenderSystem.SwapBuffers();    
}

void UpdateDisplay0CommandCache(void)
{
    for (u32 modelIndex = 0; modelIndex < MAX_MODEL_NUM; modelIndex++)
    {
        demo::Particle& particle = s_ParticleArray[modelIndex];
        
        // Updates particle positions.
        particle.Update(s_DeltaTime);
    
        // Calculates model view matrices of the particles.
        nn::math::MTX44 modelViewMatrix(s_ViewMatrix);
        nn::math::Matrix44 worldMatrix = particle.GetWorldMatrix();
        nn::math::MTX44Mult(&modelViewMatrix, &modelViewMatrix, &worldMatrix);

        // Updates the model view matrix specified by modelIndex in the command cache.
        s_CommandCache.UpdateVSUniformMatrix(modelIndex, s_ModelViewArrayIndex, modelViewMatrix);
    }
}

void nnMain(void)
{
    // Call only nn::applet::Enable to also allow execution from the HOME Menu
    // HOME Menu transitions, POWER Button presses, and sleep are all unsupported
    nn::applet::Enable();

    Initialize();
    
    bool flag = true;
    while ( flag )
    {
#ifdef USE_COMMAND_CACHE
        flag = DrawFrameCommandCache();
#else
        flag = DrawFrame();
#endif
    }

    Finalize();
}