#include <stdio.h>
#include <libgen.h>
#include <stdlib.h>
#include <sstream>
#include <cstring>

#include "Utilities.hh"

std::string sanitize(const std::string& text) {
    std::string result = text;
    for (char c : {'<', '>', ' ', ',', ':', '*', '[', ']'}) {
        std::replace(result.begin(), result.end(), c, '_');
    }
    // Catches templates with negative default values (iss #660)
    for (char c : {'-'}) {
        std::replace(result.begin(), result.end(), c, 'n');
    }
    return result ;
}

// Replace special chars for xml output
std::string & replace_special_chars( std::string & str) {

    // escape &
    size_t index = 0;
    while (index != std::string::npos) {
        index = str.find("&" , index) ;
        if ( index != std::string::npos ) {
            str.replace(index, 1, "&amp;") ;
            index += 5;
        }
    }

    // escape "
    index = 0;
    while (index != std::string::npos) {
        index = str.find("\\\"" , index) ;
        if ( index != std::string::npos ) {
            str.replace(index, 2, "&quot;") ;
        }
    }

    // escape <
    index = 0;
    while (index != std::string::npos) {
        index = str.find("<" , index) ;
        if ( index != std::string::npos ) {
            str.replace(index, 1, "&lt;") ;
        }
    }

    return str;
}

// removes leading and trailing whitespace from a string
std::string trim(const std::string& str, const std::string& whitespace ) {
    size_t strBegin = str.find_first_not_of(whitespace);
    if (strBegin == std::string::npos) {
        return "";
    }
    size_t strEnd = str.find_last_not_of(whitespace);
    size_t strRange = strEnd - strBegin + 1;

    return str.substr(strBegin, strRange);
}

bool isInUserCode( clang::CompilerInstance & ci , clang::SourceLocation sl , HeaderSearchDirs & hsd ) {
    bool ret = false ;
    char* resolved_path = getResolvedPath(ci, sl);

    if ( resolved_path != NULL ) {
        if ( hsd.isPathInUserDir(resolved_path)) {
            ret = true ;
        }
        free(resolved_path) ;
    }

    return ret ;
}

bool isInUserOrTrickCode( clang::CompilerInstance & ci , clang::SourceLocation sl , HeaderSearchDirs & hsd ) {
    bool ret = false ;
    char* resolved_path = getResolvedPath(ci, sl);
    
    if ( resolved_path != NULL ) {
        if ( hsd.isPathInUserOrTrickDir(resolved_path)) {
            ret = true ;
        }
        free(resolved_path) ;
    }
    
    return ret ;
}

std::string getFileName( clang::CompilerInstance & ci , clang::SourceLocation sl , HeaderSearchDirs & hsd ) {
    std::string file_name;
    char* resolved_path = getResolvedPath(ci, sl);

    if (resolved_path != NULL ) {
        if (hsd.isPathInUserDir(resolved_path)) {
            file_name.append(resolved_path);
        }
        free(resolved_path);
    }
    
    return file_name;
}

char * getResolvedPath(clang::CompilerInstance & ci , clang::SourceLocation sl) {
    clang::FileID fid = ci.getSourceManager().getFileID(sl) ;
    char* resolved_path = NULL;

    if ( ! fid.isInvalid() ) {
        const clang::FileEntry * fe = ci.getSourceManager().getFileEntryForID(fid) ;
        if ( fe != NULL ) {
#if (LIBCLANG_MAJOR < 4) // TODO delete when RHEL 7 no longer supported
        resolved_path = almostRealPath( fe->getName() ) ;
#elif (LIBCLANG_MAJOR >= 4 && LIBCLANG_MAJOR < 18) 
        resolved_path = almostRealPath( fe->getName().str() ) ;
#else
        const clang::CustomizableOptional<clang::FileEntryRef> cfer = ci.getSourceManager().getFileEntryRefForID(fid) ;
        if (cfer.has_value()) {
            resolved_path = almostRealPath( cfer->getName().str() ) ;
        }
        
#endif
        }
    }

    return resolved_path;
}

#include <iostream>
char * almostRealPath( const std::string& in_path ) {
    return almostRealPath(in_path.c_str());
}

/*
   This function returns almost absolute path of the directory of the incoming path.
   It does not follow the last symbolic link.

   dirname and basename may modify their argument, so make a copy of the path.
*/
char * almostRealPath( const char * in_path ) {
    char * file_copy_path = strdup(in_path) ;
    char * dir_copy_path = strdup(in_path) ;
    char * file = basename(file_copy_path) ;
    char * dir = dirname(dir_copy_path) ;
    char * resolved_path = NULL ;
    char * final_path = NULL ;
    resolved_path = realpath( dir , resolved_path) ;
    if ( resolved_path != NULL ) {
        size_t final_path_len = strlen(resolved_path) + strlen(file) + 2; 
        final_path = (char *)malloc(final_path_len) ;
        snprintf(final_path, final_path_len, "%s/%s", resolved_path , file ) ;
        free(resolved_path) ;
    }
    free(file_copy_path) ;
    free(dir_copy_path) ;

    if (!final_path) {
        std::cout << bold(color(WARNING, "Warning")) << "    ICG could not resolve realpath of " << quote(bold(in_path)) << std::endl;
    }

    return final_path ;
}

static const std::string escapeSequence = "[";
static const std::string defaultForegroundColorSequence = escapeSequence + "39m";
static const std::string boldSequence = escapeSequence + "1m";
static const std::string noBoldSequence = escapeSequence + "22m";
static const std::string underlineSequence = escapeSequence + "4m";
static const std::string noUnderlineSequence = escapeSequence + "24m";

std::string color(const Color& color, const std::string& text) {
    std::ostringstream oss;
    oss << escapeSequence << color << "m" << text << defaultForegroundColorSequence;
    return oss.str();
}

std::string bold(const std::string& text) {
    return boldSequence + text + noBoldSequence;
}

std::string underline(const std::string& text) {
    return underlineSequence + text + noUnderlineSequence;
}

std::string underline(const std::string& text, unsigned length) {
    return underline(text.substr(0, length)) + text.substr(length);
}

std::string quote(const std::string& text) {
    return "\"" + text + "\"";
}


// This function will accept version numbers with Major, Major.Minor, or Major.Minor.Patch. 
// It removes non-numerical prefixes or postfixes to the version number. The return value
// is an int with the format MMmmpp, which is what llvm LangOpts.gnucversion expects.
// If there is a problem or no verno is provided, it returns the default value. 
int gccVersionToIntOrDefault(const char* verno, int def) {
    const int buffersize = 32;
    // need mutable characters for strtok
    char verbuf[buffersize];
    if(verno == nullptr || verno[0] == '\0' || strlen(verno) >= buffersize) {
        // Invalid GCC version string, returning default GCC version
        return def;
    }
    strcpy(verbuf, verno);
    const int len = strlen(verbuf);
    const char* majMinPatch[3] = {"0", "0", "0"};
    // Setting non-numerals to the delimeter (might catch vernos with prefix or postfix)
    for(int i = 0; i < len; i++) {
        if(verbuf[i] < '0' || verbuf[i] > '9') {
            verbuf[i] = '.';
        }
    }
    char* next = strtok(verbuf, ".");
    for(int i = 0; next != nullptr && i < 3; i++) {
        majMinPatch[i] = next;
        next = strtok(nullptr, ".");
    }
    // This is the format that LLVM expects for the version number
    int result = 10000*atoi(majMinPatch[0]) + 100*atoi(majMinPatch[1]) + atoi(majMinPatch[2]);
    if(result > 999999) {
        std::cerr << "Warning: GCC_VERSION is invalid version number: " << result << ". Setting ICG to use default GCC version: " << def << std::endl;
        return def;
    }
    return result;
}