int main(int argc, char *argv[0]) {
// Declare a string variable to store a filename
std::string aFile;
string buf;
// Declare a variable to read in a JSON file
ifstream inFile;
// Check for a command line argument
if (argc != 2) {
cout << "usage: " << argv[0] << " <filename>\n";
} else {
// store the command argument as the filename
aFile = argv[1];
}
// Read in a .json file
inFile.open(aFile);
// Check that the file name was opened successfully
if (inFile.fail( )) {
// Print an error message
cout << "Error opening file.\n\n";
exit(1);
} else {
// The file was successfully opened
cout << "File opened successfully.\n\n";
}
// regular expressions for matches
regex openBraceRE(R"(\s*[\{\[])");
regex closeBraceRE(R"(\s*[\}\]])");
regex arrayRE(R"(\[(.+)\])") ;
regex emptyRE(R"(^\s*$)");
regex jLineRE(R"(\x22(\w+)\x22\s*: (.*),?)");
regex jIntRE(R"(\s*(\d+),?)");
regex jStrRE(R"(\s*\x22(\w+)\x22\s*,?)");
regex jBoolorNullRE(R"(\s*(\w+),?)");
// some matches and strings for thos matches
smatch fileTypeMatch;
smatch jLineMatch;
smatch jValMatch;
string jsonID;
string jsonVal;
bool openBraceNotFound = true;
// temp variables for valid types found
int jInt;
string jStr;
bool jBool;
string jNull = "null";
// json objects
JsonObject* jObject = new JsonObject();
JsonArray * jArray = new JsonArray();
do {
getline(inFile, buf);
// check for empty line
if(regex_search(buf, jLineMatch, emptyRE)) {
cout << "empty line...\n";
continue;
}
// check for open brace
if(regex_search(buf, jLineMatch, openBraceRE)) {
openBraceNotFound = false;
continue;
}
// if the first character is not a brace display error and exit
if (openBraceNotFound) {
cout <<"ERROR expected {...\n";
exit(1);
}
// check for close brace
if(regex_search(buf, jLineMatch, closeBraceRE)) {
break;
}
// if valid line found, save id and value
if(regex_search(buf, jLineMatch, jLineRE))
{
jsonID = jLineMatch.str(1);
jsonVal = jLineMatch.str(2);
}
// if valid line not found, put an error and exit
else {
cout << "\nERROR: Not a valid line! \n";
exit(1);
}
// if valid array found add too the object
if (regex_search(jsonVal, jValMatch, arrayRE)) {
cout << "Array matched!\n";
jArray->Add(new JsonString(jLineMatch.str(1)));
jObject->Add(jsonID, jArray);
}
// if valid integer found add it too the object
else if (regex_search(jsonVal, jValMatch, jIntRE)) {
jInt = stoi(jsonVal);
cout << "Valid Int " << jInt << " matched! \n";
jObject->Add(jsonID, new JsonNumber(jInt));
}
// if valid string found, add it to the object
else if (regex_search(jsonVal, jValMatch, jStrRE)) {
jStr = jValMatch.str(1);
cout << "Valid String " << jStr << " matched! \n";
jObject->Add(jsonID, new JsonString(jStr));
}
// finally look for bool or null
else if(regex_search(jsonVal, jValMatch, jBoolorNullRE)) {
if ("true" == jValMatch.str(1)) {
jBool = true ;
cout << "Valid bool " << jBool << " matched! \n";
jObject->Add(jsonID, new JsonBoolean(jBool));
}
else if ("false" == jValMatch.str(1)){
jBool = false ;
cout << "Valid bool " << jBool << " matched! \n";
jObject->Add(jsonID, new JsonBoolean(jBool));
}
else if ("null" == jValMatch.str(1)){
cout << "Valid null matched! \n";
jObject->Add(jsonID, new JsonNull());
}
}
// if the line from file contains anything else then exit
else {
cout << "Error invalid value...\n";
exit(1);
}
} while (!inFile.eof());
cout << endl;
jObject->Print();
cout << endl;
return 0;
}
