// Copyright 2021 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.

#ifndef SRC_PROGRAM_H_
#define SRC_PROGRAM_H_

#include <string>

#include "src/ast/function.h"
#include "src/diagnostic/diagnostic.h"
#include "src/symbol_table.h"
#include "src/type/type_manager.h"

namespace tint {

// Forward declarations
class CloneContext;

namespace ast {

class Module;

}  // namespace ast

/// Program holds the AST, Type information and SymbolTable for a tint program.
class Program {
 public:
  /// ASTNodes is an alias to BlockAllocator<ast::Node>
  using ASTNodes = BlockAllocator<ast::Node>;

  /// Constructor
  Program();

  /// Move constructor
  /// @param rhs the Program to move
  Program(Program&& rhs);

  /// Move constructor from builder
  /// @param builder the builder used to construct the program
  explicit Program(ProgramBuilder&& builder);

  /// Destructor
  ~Program();

  /// Move assignment operator
  /// @param rhs the Program to move
  /// @return this Program
  Program& operator=(Program&& rhs);

  /// @returns a reference to the program's types
  const type::Manager& Types() const {
    AssertNotMoved();
    return types_;
  }

  /// @returns a reference to the program's AST nodes storage
  const ASTNodes& Nodes() const {
    AssertNotMoved();
    return nodes_;
  }

  /// @returns a reference to the program's AST root Module
  const ast::Module& AST() const {
    AssertNotMoved();
    return *ast_;
  }

  /// @returns a reference to the program's SymbolTable
  const SymbolTable& Symbols() const {
    AssertNotMoved();
    return symbols_;
  }

  /// @returns a reference to the program's diagnostics
  const diag::List& Diagnostics() const {
    AssertNotMoved();
    return diagnostics_;
  }

  /// @return a deep copy of this program
  Program Clone() const;

  /// @return a deep copy of this Program, as a ProgramBuilder
  ProgramBuilder CloneAsBuilder() const;

  /// @returns true if the program has no error diagnostics and is not missing
  /// information
  bool IsValid() const;

  /// @returns a string describing this program.
  std::string to_str() const;

 private:
  Program(const Program&) = delete;

  /// Asserts that the program has not been moved.
  void AssertNotMoved() const;

  type::Manager types_;
  ASTNodes nodes_;
  ast::Module* ast_;
  SymbolTable symbols_;
  diag::List diagnostics_;
  bool is_valid_ = true;
  bool moved_ = false;
};

}  // namespace tint

#endif  // SRC_PROGRAM_H_