/*
 * Copyright 2017 WebAssembly Community Group participants
 *
 * 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.
 */

#ifndef wasm_ir_module_h
#define wasm_ir_module_h

#include "wasm.h"
#include "ir/manipulation.h"

namespace wasm {

namespace ModuleUtils {

// Computes the indexes in a wasm binary, i.e., with function imports
// and function implementations sharing a single index space, etc.
struct BinaryIndexes {
  std::unordered_map<Name, Index> functionIndexes;
  std::unordered_map<Name, Index> globalIndexes;

  BinaryIndexes(Module& wasm) {
    for (Index i = 0; i < wasm.imports.size(); i++) {
      auto& import = wasm.imports[i];
      if (import->kind == ExternalKind::Function) {
        auto index = functionIndexes.size();
        functionIndexes[import->name] = index;
      } else if (import->kind == ExternalKind::Global) {
        auto index = globalIndexes.size();
        globalIndexes[import->name] = index;
      }
    }
    for (Index i = 0; i < wasm.functions.size(); i++) {
      auto index = functionIndexes.size();
      functionIndexes[wasm.functions[i]->name] = index;
    }
    for (Index i = 0; i < wasm.globals.size(); i++) {
      auto index = globalIndexes.size();
      globalIndexes[wasm.globals[i]->name] = index;
    }
  }
};

inline Function* copyFunction(Function* func, Module& out) {
  auto* ret = new Function();
  ret->name = func->name;
  ret->result = func->result;
  ret->params = func->params;
  ret->vars = func->vars;
  ret->type = Name(); // start with no named type; the names in the other module may differ
  ret->localNames = func->localNames;
  ret->localIndices = func->localIndices;
  ret->debugLocations = func->debugLocations;
  ret->body = ExpressionManipulator::copy(func->body, out);
  // TODO: copy Stack IR
  assert(!func->stackIR);
  out.addFunction(ret);
  return ret;
}

inline void copyModule(Module& in, Module& out) {
  // we use names throughout, not raw points, so simple copying is fine
  // for everything *but* expressions
  for (auto& curr : in.functionTypes) {
    out.addFunctionType(new FunctionType(*curr));
  }
  for (auto& curr : in.imports) {
    out.addImport(new Import(*curr));
  }
  for (auto& curr : in.exports) {
    out.addExport(new Export(*curr));
  }
  for (auto& curr : in.functions) {
    copyFunction(curr.get(), out);
  }
  for (auto& curr : in.globals) {
    out.addGlobal(new Global(*curr));
  }
  out.table = in.table;
  for (auto& segment : out.table.segments) {
    segment.offset = ExpressionManipulator::copy(segment.offset, out);
  }
  out.memory = in.memory;
  for (auto& segment : out.memory.segments) {
    segment.offset = ExpressionManipulator::copy(segment.offset, out);
  }
  out.start = in.start;
  out.userSections = in.userSections;
  out.debugInfoFileNames = in.debugInfoFileNames;
}

} // namespace ModuleUtils

} // namespace wasm

#endif // wasm_ir_module_h