// -*- mode: C++; c-indent-level: 4; c-basic-offset: 4; indent-tabs-mode: nil; -*-
//
// api.cpp: Rcpp R/C++ interface class library -- Rcpp api
//
// Copyright (C) 2012 - 2016  Dirk Eddelbuettel and Romain Francois
//
// This file is part of Rcpp.
//
// Rcpp is free software: you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 2 of the License, or
// (at your option) any later version.
//
// Rcpp is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Rcpp.  If not, see <http://www.gnu.org/licenses/>.

#define COMPILING_RCPP

#include <Rcpp.h>

using namespace Rcpp;

#include "internal.h"
#include <R_ext/PrtUtil.h>

#ifdef RCPP_HAS_DEMANGLING
#include <cxxabi.h>
#endif

#if defined(__GNUC__) || defined(__clang__)
    #if defined(_WIN32) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__CYGWIN__) || defined(__sun) || defined(_AIX) || defined(__MUSL__)
        // do nothing
    #else
        #include <execinfo.h>

        // Extract mangled name e.g. ./test(baz+0x14)[0x400962]
        static std::string demangler_one(const char* input) {
            static std::string buffer;
            buffer = input;
            size_t last_open = buffer.find_last_of('(');
            size_t last_close = buffer.find_last_of(')');
            if (last_open == std::string::npos ||
                last_close == std::string::npos) {
              return input;
            }
            std::string function_name = buffer.substr(last_open + 1, last_close - last_open - 1);
            // Strip the +0x14 (if it exists, which it does not in earlier versions of gcc)
            size_t function_plus = function_name.find_last_of('+');
            if (function_plus != std::string::npos) {
              function_name.resize(function_plus);
            }
            buffer.replace(last_open + 1, function_name.size(), demangle(function_name));
            return buffer;
        }
    #endif
#endif


namespace Rcpp {

    namespace internal {
        namespace {
            unsigned long RNGScopeCounter = 0;
        }

        // [[Rcpp::register]]
        unsigned long enterRNGScope() {
            if (RNGScopeCounter == 0) GetRNGstate();
            RNGScopeCounter++;
            return RNGScopeCounter;
        }

        // [[Rcpp::register]]
        unsigned long exitRNGScope() {
            RNGScopeCounter--;
            if (RNGScopeCounter == 0) PutRNGstate();
            return RNGScopeCounter;
        }

        // [[Rcpp::register]]
        char* get_string_buffer() {
            static char buffer[MAXELTSIZE];
            return buffer;
        }

    }

    // [[Rcpp::register]]
    const char * type2name(SEXP x) {
        switch (TYPEOF(x)) {
        case NILSXP:	return "NILSXP";
        case SYMSXP:	return "SYMSXP";
        case RAWSXP:	return "RAWSXP";
        case LISTSXP:	return "LISTSXP";
        case CLOSXP:	return "CLOSXP";
        case ENVSXP:	return "ENVSXP";
        case PROMSXP:	return "PROMSXP";
        case LANGSXP:	return "LANGSXP";
        case SPECIALSXP:	return "SPECIALSXP";
        case BUILTINSXP:	return "BUILTINSXP";
        case CHARSXP:	return "CHARSXP";
        case LGLSXP:	return "LGLSXP";
        case INTSXP:	return "INTSXP";
        case REALSXP:	return "REALSXP";
        case CPLXSXP:	return "CPLXSXP";
        case STRSXP:	return "STRSXP";
        case DOTSXP:	return "DOTSXP";
        case ANYSXP:	return "ANYSXP";
        case VECSXP:	return "VECSXP";
        case EXPRSXP:	return "EXPRSXP";
        case BCODESXP:	return "BCODESXP";
        case EXTPTRSXP:	return "EXTPTRSXP";
        case WEAKREFSXP:	return "WEAKREFSXP";
        case S4SXP:		return "S4SXP";
        default:
        return "<unknown>";
        }
    }


} // namespace Rcpp

// [[Rcpp::register]]
std::string demangle(const std::string& name) {
    #ifdef RCPP_HAS_DEMANGLING
        std::string real_class;
        int status =-1;
        char *dem = 0;
        dem = abi::__cxa_demangle(name.c_str(), 0, 0, &status);
        if (status == 0) {
            real_class = dem;
            free(dem);
        } else {
            real_class = name;
        }
        return real_class;
    #else
        return name;
    #endif
}

// [[Rcpp::register]]
const char* short_file_name(const char* file) {
    std::string f(file);
    size_t index = f.find("/include/");
    if (index != std::string::npos) {
        f = f.substr(index + 9);
    }
    return f.c_str();
}

// [[Rcpp::internal]]
SEXP as_character_externalptr(SEXP xp) {
    char buffer[20];
    snprintf(buffer, 20, "%p", (void*)EXTPTR_PTR(xp));
    return Rcpp::wrap((const char*)buffer);
}

// [[Rcpp::internal]]
SEXP rcpp_capabilities() {
    Shield<SEXP> cap(Rf_allocVector(LGLSXP, 13));
    Shield<SEXP> names(Rf_allocVector(STRSXP, 13));
    #ifdef HAS_VARIADIC_TEMPLATES
        LOGICAL(cap)[0] = TRUE;
    #else
        LOGICAL(cap)[0] = FALSE;
    #endif
    #ifdef HAS_CXX0X_INITIALIZER_LIST
        LOGICAL(cap)[1] = TRUE;
    #else
        LOGICAL(cap)[1] = FALSE;
    #endif
    /* exceptions are always supported */
    LOGICAL(cap)[2] = TRUE;

    #ifdef HAS_TR1_UNORDERED_MAP
        LOGICAL(cap)[3] = TRUE;
    #else
       LOGICAL(cap)[3] = FALSE;
    #endif

    #ifdef HAS_TR1_UNORDERED_SET
        LOGICAL(cap)[4] = TRUE;
    #else
        LOGICAL(cap)[4] = FALSE;
    #endif

    LOGICAL(cap)[5] = TRUE;

    #ifdef RCPP_HAS_DEMANGLING
        LOGICAL(cap)[6] = TRUE;
    #else
       LOGICAL(cap)[6] = FALSE;
    #endif

       LOGICAL(cap)[7] = FALSE;

    #ifdef RCPP_HAS_LONG_LONG_TYPES
        LOGICAL(cap)[8] = TRUE;
    #else
        LOGICAL(cap)[8] = FALSE;
    #endif

    #ifdef HAS_CXX0X_UNORDERED_MAP
      LOGICAL(cap)[9] = TRUE;
    #else
      LOGICAL(cap)[9] = FALSE;
    #endif

    #ifdef HAS_CXX0X_UNORDERED_SET
      LOGICAL(cap)[10] = TRUE;
    #else
      LOGICAL(cap)[10] = FALSE;
    #endif

    #ifdef RCPP_USING_CXX11
      LOGICAL(cap)[11] = TRUE;
    #else
      LOGICAL(cap)[11] = FALSE;
    #endif

    #ifdef RCPP_NEW_DATE_DATETIME_VECTORS
      LOGICAL(cap)[12] = TRUE;
    #else
      LOGICAL(cap)[12] = FALSE;
    #endif


    SET_STRING_ELT(names, 0, Rf_mkChar("variadic templates"));
    SET_STRING_ELT(names, 1, Rf_mkChar("initializer lists"));
    SET_STRING_ELT(names, 2, Rf_mkChar("exception handling"));
    SET_STRING_ELT(names, 3, Rf_mkChar("tr1 unordered maps"));
    SET_STRING_ELT(names, 4, Rf_mkChar("tr1 unordered sets"));
    SET_STRING_ELT(names, 5, Rf_mkChar("Rcpp modules"));
    SET_STRING_ELT(names, 6, Rf_mkChar("demangling"));
    SET_STRING_ELT(names, 7, Rf_mkChar("classic api"));
    SET_STRING_ELT(names, 8, Rf_mkChar("long long"));
    SET_STRING_ELT(names, 9, Rf_mkChar("C++0x unordered maps"));
    SET_STRING_ELT(names, 10, Rf_mkChar("C++0x unordered sets"));
    SET_STRING_ELT(names, 11, Rf_mkChar("Full C++11 support"));
    SET_STRING_ELT(names, 12, Rf_mkChar("new date(time) vectors"));
    Rf_setAttrib(cap, R_NamesSymbol, names);
    return cap;
}


// [[Rcpp::internal]]
SEXP rcpp_can_use_cxx0x() {
    #if defined(HAS_VARIADIC_TEMPLATES) || defined(RCPP_USING_CXX11)
        return Rf_ScalarLogical(TRUE);
    #else
        return Rf_ScalarLogical(FALSE);
    #endif
}


// [[Rcpp::internal]]
SEXP rcpp_can_use_cxx11() {
    #if defined(RCPP_USING_CXX11)
        return Rf_ScalarLogical(TRUE);
    #else
        return Rf_ScalarLogical(FALSE);
    #endif
}


// [[Rcpp::register]]
SEXP stack_trace(const char* file, int line) {
    #if defined(__GNUC__) || defined(__clang__)
        #if defined(_WIN32) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__CYGWIN__) || defined(__sun) || defined(_AIX) || defined(__MUSL__)
            // Simpler version for Windows and *BSD
            List trace = List::create(_["file"] = file,
                                      _[ "line"  ] = line,
                                      _[ "stack" ] = "C++ stack not available on this system");
            trace.attr("class") = "Rcpp_stack_trace";
            return trace;
        #else // ! (defined(_WIN32) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__CYGWIN__) || defined(__sun) || defined(_AIX)

            /* inspired from http://tombarta.wordpress.com/2008/08/01/c-stack-traces-with-gcc/  */
            const size_t max_depth = 100;
            int stack_depth;
            void *stack_addrs[max_depth];
            char **stack_strings;

            stack_depth = backtrace(stack_addrs, max_depth);
            stack_strings = backtrace_symbols(stack_addrs, stack_depth);

            std::string current_line;

            CharacterVector res(stack_depth - 1);
            std::transform(stack_strings + 1, stack_strings + stack_depth, res.begin(), demangler_one);
            free(stack_strings); // malloc()ed by backtrace_symbols

            List trace = List::create(_["file" ] = file,
                                      _["line" ] = line,
                                      _["stack"] = res);
            trace.attr("class") = "Rcpp_stack_trace";
            return trace;
        #endif
    #else /* !defined( __GNUC__ ) */
        return R_NilValue;
    #endif
}

// // [ [ Rcpp::register ] ]
// void print(SEXP s) {
//     Rf_PrintValue(s);           // defined in Rinternals.h
// }

// }}}