/*
 * (C) Copyright 1996- ECMWF.
 *
 * This software is licensed under the terms of the Apache Licence Version 2.0
 * which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
 * In applying this licence, ECMWF does not waive the privileges and immunities
 * granted to it by virtue of its status as an intergovernmental organisation nor
 * does it submit to any jurisdiction.
 */

/// @author Baudouin Raoult
/// @author Tiago Quintino
/// @date Sep 2012

#include "eckit/parser/StreamParser.h"
#include "eckit/os/BackTrace.h"
#include "eckit/utils/Translator.h"

#include "eckit/log/Log.h"


namespace eckit {

//----------------------------------------------------------------------------------------------------------------------

StreamParser::StreamParser(std::istream& in, bool comments, const char* comment) :
    line_(0), pos_(0), comments_(comments), in_(in) {
    while (*comment) {
        comment_.insert(*comment++);
    }
}

char StreamParser::_get() {
    char c = 0;
    in_.get(c);
    pos_++;
    if (c == '\n' || c == '\r') {
        line_++;
        pos_ = 0;
        if (c == '\r' && in_.peek() == '\n') {
            in_.get(c);
        }
    }
    return c;
}


char StreamParser::_peek() {
    char c = in_.peek();
    if (c == '\r') {
        c = '\n';
    }
    return c;
}

bool StreamParser::_eof() {
    return in_.eof();
}

void StreamParser::putback(char c) {
    in_.putback(c);
}

char StreamParser::peek(bool spaces) {
    for (;;) {
        char c = _peek();

        if (_eof())
            return 0;

        if (comments_ && comment_.find(c) != comment_.end()) {
            while (_peek() != '\n' && !_eof()) {
                _get();
            }
            if (_eof()) {
                return 0;
            }
            return peek(spaces);
        }

        if (spaces || !isspace(c)) {
            //            std::cout << "peek(" << c << ")" << std::endl;
            return c;
        }
        else {
            //            std::cout << "skip(" << c << ")" << std::endl;
            _get();
        }
    }
}

char StreamParser::next(bool spaces) {
    for (;;) {
        char c = _get();
        if (_eof())
            throw StreamParser::Error(std::string("StreamParser::next reached eof"));

        if (comments_ && comment_.find(c) != comment_.end()) {
            while (_peek() != '\n' && !_eof()) {
                _get();
            }
            if (_eof()) {
                throw StreamParser::Error(std::string("StreamParser::next reached eof"));
            }
            return next(spaces);
        }

        if (spaces || !isspace(c)) {
            //            std::cout << "next(" << c << ")" << std::endl;
            return c;
        }
    }
}

void StreamParser::consume(char c) {
    char n = next();
    if (c != n)
        throw StreamParser::Error(std::string("StreamParser::consume expecting '") + c + "', got '" + n + "'",
                                  line_ + 1);
}

void StreamParser::consume(const char* p) {
    while (*p)
        consume(*p++);
}


StreamParser::Error::Error(const std::string& what, size_t line) :
    Exception(what) {
    if (line) {
        std::ostringstream oss;
        oss << "Line: " << line << " " << what;
        reason(oss.str());
    }
}

//----------------------------------------------------------------------------------------------------------------------

}  // namespace eckit
