// Copyright 2023 The IREE Authors
//
// Licensed under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

#include "experimental/metal/pipeline_layout.h"

#include <stddef.h>

#include "iree/base/api.h"
#include "iree/base/tracing.h"

//===------------------------------------------------------------------------------------------===//
// iree_hal_metal_descriptor_set_layout_t
//===------------------------------------------------------------------------------------------===//

typedef struct iree_hal_metal_descriptor_set_layout_t {
  // Abstract resource used for injecting reference counting and vtable; must be at offset 0.
  iree_hal_resource_t resource;

  iree_allocator_t host_allocator;

  iree_host_size_t binding_count;
  iree_hal_descriptor_set_layout_binding_t bindings[];
} iree_hal_metal_descriptor_set_layout_t;

static const iree_hal_descriptor_set_layout_vtable_t iree_hal_metal_descriptor_set_layout_vtable;

static iree_hal_metal_descriptor_set_layout_t* iree_hal_metal_descriptor_set_layout_cast(
    iree_hal_descriptor_set_layout_t* base_value) {
  IREE_HAL_ASSERT_TYPE(base_value, &iree_hal_metal_descriptor_set_layout_vtable);
  return (iree_hal_metal_descriptor_set_layout_t*)base_value;
}

static const iree_hal_metal_descriptor_set_layout_t*
iree_hal_metal_descriptor_set_layout_const_cast(
    const iree_hal_descriptor_set_layout_t* base_value) {
  IREE_HAL_ASSERT_TYPE(base_value, &iree_hal_metal_descriptor_set_layout_vtable);
  return (const iree_hal_metal_descriptor_set_layout_t*)base_value;
}

iree_status_t iree_hal_metal_descriptor_set_layout_create(
    iree_hal_descriptor_set_layout_flags_t flags, iree_host_size_t binding_count,
    const iree_hal_descriptor_set_layout_binding_t* bindings, iree_allocator_t host_allocator,
    iree_hal_descriptor_set_layout_t** out_descriptor_set_layout) {
  IREE_ASSERT_ARGUMENT(!binding_count || bindings);
  IREE_ASSERT_ARGUMENT(out_descriptor_set_layout);
  *out_descriptor_set_layout = NULL;
  IREE_TRACE_ZONE_BEGIN(z0);

  iree_hal_metal_descriptor_set_layout_t* descriptor_set_layout = NULL;
  iree_host_size_t bindings_size = binding_count * sizeof(descriptor_set_layout->bindings[0]);
  iree_status_t status =
      iree_allocator_malloc(host_allocator, sizeof(*descriptor_set_layout) + bindings_size,
                            (void**)&descriptor_set_layout);
  if (iree_status_is_ok(status)) {
    iree_hal_resource_initialize(&iree_hal_metal_descriptor_set_layout_vtable,
                                 &descriptor_set_layout->resource);
    descriptor_set_layout->host_allocator = host_allocator;
    descriptor_set_layout->binding_count = binding_count;
    memcpy(descriptor_set_layout->bindings, bindings, bindings_size);
    *out_descriptor_set_layout = (iree_hal_descriptor_set_layout_t*)descriptor_set_layout;
  }
  IREE_TRACE_ZONE_END(z0);
  return status;
}

static void iree_hal_metal_descriptor_set_layout_destroy(
    iree_hal_descriptor_set_layout_t* base_descriptor_set_layout) {
  iree_hal_metal_descriptor_set_layout_t* descriptor_set_layout =
      iree_hal_metal_descriptor_set_layout_cast(base_descriptor_set_layout);
  IREE_TRACE_ZONE_BEGIN(z0);

  iree_allocator_free(descriptor_set_layout->host_allocator, descriptor_set_layout);

  IREE_TRACE_ZONE_END(z0);
}

const iree_hal_descriptor_set_layout_binding_t* iree_hal_metal_descriptor_set_layout_binding(
    const iree_hal_descriptor_set_layout_t* base_descriptor_set_layout, uint32_t binding) {
  const iree_hal_metal_descriptor_set_layout_t* descriptor_set_layout =
      iree_hal_metal_descriptor_set_layout_const_cast(base_descriptor_set_layout);
  for (iree_host_size_t i = 0; i < descriptor_set_layout->binding_count; ++i) {
    if (descriptor_set_layout->bindings[i].binding == binding) {
      return &descriptor_set_layout->bindings[i];
    }
  }
  return NULL;
}

iree_host_size_t iree_hal_metal_descriptor_set_layout_binding_count(
    const iree_hal_descriptor_set_layout_t* base_descriptor_set_layout) {
  const iree_hal_metal_descriptor_set_layout_t* descriptor_set_layout =
      iree_hal_metal_descriptor_set_layout_const_cast(base_descriptor_set_layout);
  return descriptor_set_layout->binding_count;
}

static const iree_hal_descriptor_set_layout_vtable_t iree_hal_metal_descriptor_set_layout_vtable = {
    .destroy = iree_hal_metal_descriptor_set_layout_destroy,
};

//===------------------------------------------------------------------------------------------===//
// iree_hal_metal_pipeline_layout_t
//===------------------------------------------------------------------------------------------===//

typedef struct iree_hal_metal_pipeline_layout_t {
  // Abstract resource used for injecting reference counting and vtable; must be at offset 0.
  iree_hal_resource_t resource;

  iree_allocator_t host_allocator;

  iree_host_size_t push_constant_count;

  iree_host_size_t set_layout_count;
  iree_hal_descriptor_set_layout_t* set_layouts[];
} iree_hal_metal_pipeline_layout_t;

static const iree_hal_pipeline_layout_vtable_t iree_hal_metal_pipeline_layout_vtable;

static iree_hal_metal_pipeline_layout_t* iree_hal_metal_pipeline_layout_cast(
    iree_hal_pipeline_layout_t* base_value) {
  IREE_HAL_ASSERT_TYPE(base_value, &iree_hal_metal_pipeline_layout_vtable);
  return (iree_hal_metal_pipeline_layout_t*)base_value;
}

static const iree_hal_metal_pipeline_layout_t* iree_hal_metal_pipeline_layout_const_cast(
    const iree_hal_pipeline_layout_t* base_value) {
  IREE_HAL_ASSERT_TYPE(base_value, &iree_hal_metal_pipeline_layout_vtable);
  return (const iree_hal_metal_pipeline_layout_t*)base_value;
}

iree_status_t iree_hal_metal_pipeline_layout_create(
    iree_host_size_t set_layout_count, iree_hal_descriptor_set_layout_t* const* set_layouts,
    iree_host_size_t push_constant_count, iree_allocator_t host_allocator,
    iree_hal_pipeline_layout_t** out_pipeline_layout) {
  IREE_ASSERT_ARGUMENT(!set_layout_count || set_layouts);
  IREE_ASSERT_ARGUMENT(out_pipeline_layout);
  *out_pipeline_layout = NULL;
  IREE_TRACE_ZONE_BEGIN(z0);

  iree_hal_metal_pipeline_layout_t* pipeline_layout = NULL;
  iree_host_size_t total_size =
      sizeof(*pipeline_layout) + set_layout_count * sizeof(pipeline_layout->set_layouts[0]);
  iree_status_t status =
      iree_allocator_malloc(host_allocator, total_size, (void**)&pipeline_layout);
  if (iree_status_is_ok(status)) {
    iree_hal_resource_initialize(&iree_hal_metal_pipeline_layout_vtable,
                                 &pipeline_layout->resource);
    pipeline_layout->host_allocator = host_allocator;
    pipeline_layout->push_constant_count = push_constant_count;
    pipeline_layout->set_layout_count = set_layout_count;
    for (iree_host_size_t i = 0; i < set_layout_count; ++i) {
      pipeline_layout->set_layouts[i] = set_layouts[i];
      iree_hal_descriptor_set_layout_retain(set_layouts[i]);
    }
    *out_pipeline_layout = (iree_hal_pipeline_layout_t*)pipeline_layout;
  }
  IREE_TRACE_ZONE_END(z0);
  return status;
}

static void iree_hal_metal_pipeline_layout_destroy(
    iree_hal_pipeline_layout_t* base_pipeline_layout) {
  iree_hal_metal_pipeline_layout_t* pipeline_layout =
      iree_hal_metal_pipeline_layout_cast(base_pipeline_layout);
  IREE_TRACE_ZONE_BEGIN(z0);

  for (iree_host_size_t i = 0; i < pipeline_layout->set_layout_count; ++i) {
    iree_hal_descriptor_set_layout_release(pipeline_layout->set_layouts[i]);
  }
  iree_allocator_free(pipeline_layout->host_allocator, pipeline_layout);

  IREE_TRACE_ZONE_END(z0);
}

const iree_hal_descriptor_set_layout_t* iree_hal_metal_pipeline_layout_descriptor_set_layout(
    const iree_hal_pipeline_layout_t* base_pipeline_layout, uint32_t set) {
  const iree_hal_metal_pipeline_layout_t* pipeline_layout =
      iree_hal_metal_pipeline_layout_const_cast(base_pipeline_layout);
  if (set < pipeline_layout->set_layout_count) return pipeline_layout->set_layouts[set];
  return NULL;
}

iree_host_size_t iree_hal_metal_pipeline_layout_descriptor_set_count(
    const iree_hal_pipeline_layout_t* base_pipeline_layout) {
  const iree_hal_metal_pipeline_layout_t* pipeline_layout =
      iree_hal_metal_pipeline_layout_const_cast(base_pipeline_layout);
  return pipeline_layout->set_layout_count;
}

iree_host_size_t iree_hal_metal_pipeline_layout_push_constant_count(
    const iree_hal_pipeline_layout_t* base_pipeline_layout) {
  const iree_hal_metal_pipeline_layout_t* pipeline_layout =
      iree_hal_metal_pipeline_layout_const_cast(base_pipeline_layout);
  return pipeline_layout->push_constant_count;
}

static const iree_hal_pipeline_layout_vtable_t iree_hal_metal_pipeline_layout_vtable = {
    .destroy = iree_hal_metal_pipeline_layout_destroy,
};