/*
 * Copyright 2018 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifndef GrMtlGpuCommandBuffer_DEFINED
#define GrMtlGpuCommandBuffer_DEFINED

#include "src/gpu/GrGpuCommandBuffer.h"
#include "src/gpu/GrMesh.h"
#include "src/gpu/GrOpFlushState.h"
#include "src/gpu/mtl/GrMtlGpu.h"

#import <Metal/Metal.h>

typedef uint32_t GrColor;
class GrMtlBuffer;
class GrMtlPipelineState;
class GrMtlRenderTarget;

class GrMtlGpuTextureCommandBuffer : public GrGpuTextureCommandBuffer {
public:
    GrMtlGpuTextureCommandBuffer(GrMtlGpu* gpu, GrTexture* texture, GrSurfaceOrigin origin)
            : INHERITED(texture, origin)
            , fGpu(gpu) {
    }

    ~GrMtlGpuTextureCommandBuffer() override {}

    void copy(GrSurface* src, const SkIRect& srcRect, const SkIPoint& dstPoint) override {
        fGpu->copySurface(fTexture, src, srcRect, dstPoint);
    }
    void transferFrom(const SkIRect& srcRect, GrColorType bufferColorType,
                      GrGpuBuffer* transferBuffer, size_t offset) override {
        fGpu->transferPixelsFrom(fTexture, srcRect.fLeft, srcRect.fTop, srcRect.width(),
                                 srcRect.height(), bufferColorType, transferBuffer, offset);
    }
    void insertEventMarker(const char* msg) override {}

private:
    GrMtlGpu* fGpu;

    typedef GrGpuTextureCommandBuffer INHERITED;
};

class GrMtlGpuRTCommandBuffer : public GrGpuRTCommandBuffer, private GrMesh::SendToGpuImpl {
public:
    GrMtlGpuRTCommandBuffer(GrMtlGpu* gpu, GrRenderTarget* rt, GrSurfaceOrigin origin,
                            const SkRect& bounds,
                            const GrGpuRTCommandBuffer::LoadAndStoreInfo& colorInfo,
                            const GrGpuRTCommandBuffer::StencilLoadAndStoreInfo& stencilInfo);

    ~GrMtlGpuRTCommandBuffer() override;

    void begin() override {}
    void end() override {}

    void insertEventMarker(const char* msg) override {}

    void initRenderState(id<MTLRenderCommandEncoder>);

    void inlineUpload(GrOpFlushState* state, GrDeferredTextureUploadFn& upload) override {
        // TODO: this could be more efficient
        state->doUpload(upload);
    }
    void transferFrom(const SkIRect& srcRect, GrColorType bufferColorType,
                      GrGpuBuffer* transferBuffer, size_t offset) override;
    void copy(GrSurface* src, const SkIRect& srcRect, const SkIPoint& dstPoint) override;

    void submit();

private:
    GrGpu* gpu() override { return fGpu; }

    GrMtlPipelineState* prepareDrawState(
            const GrPrimitiveProcessor& primProc,
            const GrPipeline& pipeline,
            const GrPipeline::FixedDynamicState* fixedDynamicState,
            GrPrimitiveType primType);

    void onDraw(const GrPrimitiveProcessor& primProc,
                const GrPipeline& pipeline,
                const GrPipeline::FixedDynamicState* fixedDynamicState,
                const GrPipeline::DynamicStateArrays* dynamicStateArrays,
                const GrMesh mesh[],
                int meshCount,
                const SkRect& bounds) override;

    void onClear(const GrFixedClip& clip, const SkPMColor4f& color) override;

    void onClearStencilClip(const GrFixedClip& clip, bool insideStencilMask) override;

    void setupRenderPass(const GrGpuRTCommandBuffer::LoadAndStoreInfo& colorInfo,
                         const GrGpuRTCommandBuffer::StencilLoadAndStoreInfo& stencilInfo);

    void bindGeometry(const GrBuffer* vertexBuffer, size_t vertexOffset,
                      const GrBuffer* instanceBuffer);

    // GrMesh::SendToGpuImpl methods. These issue the actual Metal draw commands.
    // Marked final as a hint to the compiler to not use virtual dispatch.
    void sendMeshToGpu(GrPrimitiveType primType, const GrBuffer* vertexBuffer, int vertexCount,
                       int baseVertex) final;

    void sendIndexedMeshToGpu(GrPrimitiveType primType, const GrBuffer* indexBuffer, int indexCount,
                              int baseIndex, uint16_t /*minIndexValue*/, uint16_t /*maxIndexValue*/,
                              const GrBuffer* vertexBuffer, int baseVertex,
                              GrPrimitiveRestart restart) final;

    void sendInstancedMeshToGpu(GrPrimitiveType, const GrBuffer* vertexBuffer, int vertexCount,
                                int baseVertex, const GrBuffer* instanceBuffer, int instanceCount,
                                int baseInstance) final;

    void sendIndexedInstancedMeshToGpu(GrPrimitiveType, const GrBuffer* indexBuffer, int indexCount,
                                       int baseIndex, const GrBuffer* vertexBuffer, int baseVertex,
                                       const GrBuffer* instanceBuffer, int instanceCount,
                                       int baseInstance, GrPrimitiveRestart) final;

    void setVertexBuffer(id<MTLRenderCommandEncoder>, const GrMtlBuffer*, size_t offset,
                         size_t index);
    void resetBufferBindings();
    void precreateCmdEncoder();

    GrMtlGpu*                   fGpu;
    // GrRenderTargetProxy bounds
#ifdef SK_DEBUG
    SkRect                      fRTBounds;
#endif

    id<MTLRenderCommandEncoder> fActiveRenderCmdEncoder;
    MTLRenderPassDescriptor*    fRenderPassDesc;
    SkRect                      fBounds;
    size_t                      fCurrentVertexStride;

    static constexpr size_t kNumBindings = GrMtlUniformHandler::kLastUniformBinding + 3;
    struct {
        id<MTLBuffer> fBuffer;
        size_t fOffset;
    } fBufferBindings[kNumBindings];

    typedef GrGpuRTCommandBuffer INHERITED;
};

#endif