//
// Copyright (c) 2011 The ANGLE Project Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//

#include "compiler/preprocessor/Preprocessor.h"

#include "common/debug.h"
#include "compiler/preprocessor/DiagnosticsBase.h"
#include "compiler/preprocessor/DirectiveParser.h"
#include "compiler/preprocessor/Macro.h"
#include "compiler/preprocessor/MacroExpander.h"
#include "compiler/preprocessor/Token.h"
#include "compiler/preprocessor/Tokenizer.h"

namespace pp
{

struct PreprocessorImpl
{
    Diagnostics *diagnostics;
    MacroSet macroSet;
    Tokenizer tokenizer;
    DirectiveParser directiveParser;
    MacroExpander macroExpander;

    PreprocessorImpl(Diagnostics *diag,
                     DirectiveHandler *directiveHandler,
                     const PreprocessorSettings &settings)
        : diagnostics(diag),
          tokenizer(diag),
          directiveParser(&tokenizer,
                          &macroSet,
                          diag,
                          directiveHandler,
                          settings.maxMacroExpansionDepth),
          macroExpander(&directiveParser, &macroSet, diag, settings.maxMacroExpansionDepth)
    {
    }
};

Preprocessor::Preprocessor(Diagnostics *diagnostics,
                           DirectiveHandler *directiveHandler,
                           const PreprocessorSettings &settings)
{
    mImpl = new PreprocessorImpl(diagnostics, directiveHandler, settings);
}

Preprocessor::~Preprocessor()
{
    delete mImpl;
}

bool Preprocessor::init(size_t count,
                        const char * const string[],
                        const int length[])
{
    static const int kDefaultGLSLVersion = 100;

    // Add standard pre-defined macros.
    predefineMacro("__LINE__", 0);
    predefineMacro("__FILE__", 0);
    predefineMacro("__VERSION__", kDefaultGLSLVersion);
    predefineMacro("GL_ES", 1);

    return mImpl->tokenizer.init(count, string, length);
}

void Preprocessor::predefineMacro(const char *name, int value)
{
    PredefineMacro(&mImpl->macroSet, name, value);
}

void Preprocessor::lex(Token *token)
{
    bool validToken = false;
    while (!validToken)
    {
        mImpl->macroExpander.lex(token);
        switch (token->type)
        {
          // We should not be returning internal preprocessing tokens.
          // Convert preprocessing tokens to compiler tokens or report
          // diagnostics.
          case Token::PP_HASH:
              UNREACHABLE();
              break;
          case Token::PP_NUMBER:
            mImpl->diagnostics->report(Diagnostics::PP_INVALID_NUMBER,
                                       token->location, token->text);
            break;
          case Token::PP_OTHER:
            mImpl->diagnostics->report(Diagnostics::PP_INVALID_CHARACTER,
                                       token->location, token->text);
            break;
          default:
            validToken = true;
            break;
        }
    }
}

void Preprocessor::setMaxTokenSize(size_t maxTokenSize)
{
    mImpl->tokenizer.setMaxTokenSize(maxTokenSize);
}

}  // namespace pp
