// Copyright 2022 The Tint Authors.
//
// 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 "src/tint/writer/spirv/generator_impl.h"

#include <utility>
#include <vector>

#include "src/tint/transform/add_empty_entry_point.h"
#include "src/tint/transform/add_spirv_block_attribute.h"
#include "src/tint/transform/builtin_polyfill.h"
#include "src/tint/transform/canonicalize_entry_point_io.h"
#include "src/tint/transform/expand_compound_assignment.h"
#include "src/tint/transform/fold_constants.h"
#include "src/tint/transform/for_loop_to_loop.h"
#include "src/tint/transform/manager.h"
#include "src/tint/transform/promote_side_effects_to_decl.h"
#include "src/tint/transform/remove_unreachable_statements.h"
#include "src/tint/transform/simplify_pointers.h"
#include "src/tint/transform/unshadow.h"
#include "src/tint/transform/unwind_discard_functions.h"
#include "src/tint/transform/var_for_dynamic_index.h"
#include "src/tint/transform/vectorize_scalar_matrix_constructors.h"
#include "src/tint/transform/zero_init_workgroup_memory.h"
#include "src/tint/writer/generate_external_texture_bindings.h"

namespace tint::writer::spirv {

SanitizedResult Sanitize(const Program* in, const Options& options) {
  transform::Manager manager;
  transform::DataMap data;

  {  // Builtin polyfills
    transform::BuiltinPolyfill::Builtins polyfills;
    polyfills.count_leading_zeros = true;
    polyfills.count_trailing_zeros = true;
    polyfills.extract_bits =
        transform::BuiltinPolyfill::Level::kClampParameters;
    polyfills.first_leading_bit = true;
    polyfills.first_trailing_bit = true;
    polyfills.insert_bits = transform::BuiltinPolyfill::Level::kClampParameters;
    data.Add<transform::BuiltinPolyfill::Config>(polyfills);
    manager.Add<transform::BuiltinPolyfill>();
  }

  if (options.generate_external_texture_bindings) {
    auto new_bindings_map = GenerateExternalTextureBindings(in);
    data.Add<transform::MultiplanarExternalTexture::NewBindingPoints>(
        new_bindings_map);
  }
  manager.Add<transform::MultiplanarExternalTexture>();

  manager.Add<transform::Unshadow>();
  bool disable_workgroup_init_in_sanitizer =
      options.disable_workgroup_init ||
      options.use_zero_initialize_workgroup_memory_extension;
  if (!disable_workgroup_init_in_sanitizer) {
    manager.Add<transform::ZeroInitWorkgroupMemory>();
  }
  manager.Add<transform::RemoveUnreachableStatements>();
  manager.Add<transform::ExpandCompoundAssignment>();
  manager.Add<transform::PromoteSideEffectsToDecl>();
  manager.Add<transform::UnwindDiscardFunctions>();
  manager.Add<transform::SimplifyPointers>();  // Required for arrayLength()
  manager.Add<transform::FoldConstants>();
  manager.Add<transform::VectorizeScalarMatrixConstructors>();
  manager.Add<transform::ForLoopToLoop>();  // Must come after
                                            // ZeroInitWorkgroupMemory
  manager.Add<transform::CanonicalizeEntryPointIO>();
  manager.Add<transform::AddEmptyEntryPoint>();
  manager.Add<transform::AddSpirvBlockAttribute>();
  manager.Add<transform::VarForDynamicIndex>();

  data.Add<transform::CanonicalizeEntryPointIO::Config>(
      transform::CanonicalizeEntryPointIO::Config(
          transform::CanonicalizeEntryPointIO::ShaderStyle::kSpirv, 0xFFFFFFFF,
          options.emit_vertex_point_size));

  SanitizedResult result;
  result.program = std::move(manager.Run(in, data).program);
  return result;
}

GeneratorImpl::GeneratorImpl(const Program* program,
                             bool zero_initialize_workgroup_memory)
    : builder_(program, zero_initialize_workgroup_memory) {}

bool GeneratorImpl::Generate() {
  if (builder_.Build()) {
    writer_.WriteHeader(builder_.id_bound());
    writer_.WriteBuilder(&builder_);
    return true;
  }
  return false;
}

const std::vector<uint32_t>& GeneratorImpl::result() const {
  return writer_.result();
}

std::vector<uint32_t>& GeneratorImpl::result() {
  return writer_.result();
}

std::string GeneratorImpl::error() const {
  return builder_.error();
}

}  // namespace tint::writer::spirv