QString FileHelper::extractGenericFeature(const QString &featureToExtract) const
{
QString feature;
TagLib::PropertyMap p = _file->properties();
if (p.contains(featureToExtract.toStdString().data())) {
TagLib::StringList list = p[featureToExtract.toStdString().data()];
if (!list.isEmpty()) {
feature = list.front().toCString(true);
}
}
return feature;
}
BlockResult Block::eval(const TagLib::PropertyMap& metadata)
{
BlockResult result;
std::sort(this->variables.begin(), this->variables.end() ,
[](Block::Variable a, Block::Variable b) {
return a.pos < b.pos;
});
std::sort(this->functions.begin(), this->functions.end() ,
[](Block::Function a, Block::Function b) {
return a.pos < b.pos;
});
result.success = false;
result.result = this->parsed_statement;
int offset = 0;
auto var_itr = this->variables.begin();
auto func_itr = this->functions.begin();
// Iterate over the Function and Variables lists in order of appearance in the raw statement
while (var_itr != this->variables.end() || func_itr != this->functions.end()) {
bool eval_var = true;
// Decide if the next item to be evaluated should be a variable or a function call
if (var_itr == this->variables.end()) {
eval_var = false;
} else if (func_itr != this->functions.end()) {
// Check the positions of the statements in the raw string
if ((*var_itr).raw_pos > (*func_itr).raw_pos) {
eval_var = false;
}
}
if (eval_var) {
if (metadata.contains((*var_itr).name)) {
// insert at the index of the variable
// TODO : alias some names, e.g. tacknumber -> track
std::string meta = metadata[(*var_itr).name].toString().toCString(false);
result.result.insert((*var_itr).pos + offset, meta);
offset += meta.length();
result.success = true;
}
} else {
if (FunctionMap.find((*func_itr).name) != FunctionMap.end()) {
// Call function
BlockResult func_result = FunctionMap[(*func_itr).name].eval(metadata, (*func_itr).args);
// OR'd to keep existing successes
result.success |= func_result.success;
result.result.insert((*func_itr).pos + offset, func_result.result);
offset += func_result.result.length();
} else {
// Throw unknown function exception
}
}
if (eval_var) {
var_itr++;
} else {
func_itr++;
}
}
/**
* Using this conversion from String to integer it will allow for the
* convention of:
* "c3po" → 0
* "4.8" → 4
* "-12" → -12
* "- 12" → 0
*/
std::stringstream ss(result.result);
ss >> result.value;
return result;
}