looqs/shared/looqsquery.cpp
Albert S a6ddcef0c0 shared: LooqsQuery: Fix logic of implicit AND booleans. Add 'limit:' support
Add implicit AND booleans at the end.

This fixes a number of issues in LooqsQuery:

(1) A query like a b c p:(something) would fail, because
a b c get merged into one word. This happens at the end.

lonewords are special and do not become a token immediatly. So previous
logic to add implicit ANDs does not apply.

(2) Negations were also broken with lonewords.

(3) The TokenType enum fields were too narrow to be useful for the bitmask

Independent of that, add support for 'limit:'
2022-06-05 14:39:57 +02:00

349 rivejä
7.6 KiB
C++

#include <QStack>
#include <QRegularExpression>
#include <QSqlQuery>
#include <QSqlError>
#include <QStringList>
#include <QDebug>
#include <optional>
#include <algorithm>
#include "looqsquery.h"
const QVector<Token> &LooqsQuery::getTokens() const
{
return tokens;
}
const QVector<SortCondition> &LooqsQuery::getSortConditions() const
{
return sortConditions;
}
QueryType LooqsQuery::getQueryType()
{
return static_cast<QueryType>(tokensMask & COMBINED);
}
bool LooqsQuery::hasContentSearch()
{
return (this->getTokensMask() & FILTER_CONTENT) == FILTER_CONTENT;
}
bool LooqsQuery::hasPathSearch()
{
return (this->getTokensMask() & FILTER_PATH) == FILTER_PATH;
}
void LooqsQuery::addSortCondition(SortCondition sc)
{
this->sortConditions.append(sc);
}
bool LooqsQuery::checkParanthesis(QString expression)
{
QStack<QChar> open;
QStack<QChar> close;
bool inQuotes = false;
for(QChar &c : expression)
{
if(!inQuotes)
{
if(c == '(')
{
open.push(c);
}
if(c == ')')
{
close.push(c);
}
}
if(c == '"')
{
inQuotes = !inQuotes;
}
}
if(open.size() != close.size())
{
return false;
}
while(!open.empty() && !close.empty())
{
QChar o = open.pop();
QChar c = close.pop();
if(o != '(' && c != ')')
{
return false;
}
}
return true;
}
std::optional<QueryField> fromString(QString fieldString)
{
if(fieldString == "path" || fieldString == "file.path")
{
return FILE_PATH;
}
else if(fieldString == "mtime" || fieldString == "file.mtime")
{
return FILE_MTIME;
}
else if(fieldString == "size" || fieldString == "file.size")
{
return FILE_SIZE;
}
else if(fieldString == "content.text")
{
return CONTENT_TEXT;
}
else if(fieldString == "content.page" || fieldString == "page")
{
return CONTENT_TEXT_PAGE;
}
return {};
}
// sort:(mtime desc, page asc)
QVector<SortCondition> createSortConditions(QString sortExpression)
{
QVector<SortCondition> result;
QStringList splitted_inner = sortExpression.split(",");
for(int i = 0; i < splitted_inner.length(); i++)
{
QStringList splitted = splitted_inner[i].split(" ");
if(splitted.length() < 1 || splitted.length() > 2)
{
throw LooqsGeneralException("sort specifier must have format [field] (asc|desc)");
}
QString field = splitted[0];
auto queryField = fromString(field);
if(!queryField)
{
throw LooqsGeneralException("Unknown sort field supplied");
}
SortOrder order;
if(splitted.length() == 2)
{
QString orderstr = splitted[1];
if(orderstr.compare("asc", Qt::CaseInsensitive) == 0)
{
order = ASC;
}
else if(orderstr.compare("desc", Qt::CaseInsensitive) == 0)
{
order = DESC;
}
else
{
throw LooqsGeneralException("Unknown order specifier: " + orderstr);
}
}
else
{
order = ASC;
}
SortCondition condition;
condition.field = queryField.value();
condition.order = order;
result.append(condition);
}
return result;
}
void LooqsQuery::addToken(Token t)
{
tokens.append(t);
tokensMask |= t.type;
}
/* Builds the query from the supplied expression
*
* AND is the default boolean operator, when the user does not provide any
* thus, "Downloads zip" becomes essentailly "path.contains:(Downloads) AND path.contains:(zip)"
*
* TODO: It's a bit ugly still*/
LooqsQuery LooqsQuery::build(QString expression, TokenType loneWordsTokenType, bool mergeLoneWords)
{
if(expression.isEmpty())
{
return LooqsQuery{};
}
if(!checkParanthesis(expression))
{
throw LooqsGeneralException("Invalid paranthesis");
}
QStringList loneWords;
LooqsQuery result;
QRegularExpression rx("((?<filtername>(\\.|\\w)+):(?<args>\\((?<innerargs>[^\\)]+)\\)|([\\w,])+)|(?<boolean>AND|OR)"
"|(?<negation>!)|(?<bracket>\\(|\\))|(?<loneword>[\"\\w]+))");
QRegularExpressionMatchIterator i = rx.globalMatch(expression);
auto previousWasBool = [&result] { return !result.tokens.empty() && ((result.tokens.last().type & BOOL) == BOOL); };
auto previousWas = [&result](TokenType t) { return !result.tokens.empty() && (result.tokens.last().type == t); };
while(i.hasNext())
{
QRegularExpressionMatch m = i.next();
QString boolean = m.captured("boolean");
QString negation = m.captured("negation");
QString filtername = m.captured("filtername");
QString bracket = m.captured("bracket");
QString loneword = m.captured("loneword");
if(boolean != "")
{
if(previousWasBool())
{
throw LooqsGeneralException("Can't have two booleans following each other");
}
if(previousWas(NEGATION))
{
throw LooqsGeneralException("Can't have a negation preceeding a boolean");
}
if(boolean == "AND")
{
result.addToken(Token(BOOL_AND));
}
else if(boolean == "OR")
{
result.addToken(Token(BOOL_OR));
}
}
if(negation != "")
{
if(previousWas(NEGATION))
{
throw LooqsGeneralException("Can't have two negations following each other");
}
result.addToken(Token(NEGATION));
}
if(bracket != "")
{
if(bracket == "(")
{
result.addToken(Token(BRACKET_OPEN));
}
else
{
result.addToken(Token(BRACKET_CLOSE));
}
}
if(loneword != "")
{
if(mergeLoneWords)
{
loneWords.append(loneword);
}
else
{
result.addToken(Token(loneWordsTokenType, loneword));
}
}
if(filtername != "")
{
TokenType tokenType = WORD;
QString value = m.captured("innerargs");
if(value == "")
{
value = m.captured("args");
}
if(value == "")
{
throw LooqsGeneralException("value cannot be empty for filters");
}
if(filtername == "p" || filtername == "path.contains")
{
tokenType = FILTER_PATH_CONTAINS;
}
else if(filtername == "pb" || filtername == "path.starts")
{
tokenType = FILTER_PATH_STARTS;
}
else if(filtername == "pe" || filtername == "path.ends")
{
tokenType = FILTER_PATH_ENDS;
}
else if(filtername == "file.size" || filtername == "size")
{
tokenType = FILTER_PATH_SIZE;
}
else if(filtername == "c" || filtername == "contains")
{
tokenType = FILTER_CONTENT_CONTAINS;
}
else if(filtername == "page" || filtername == "content.page")
{
tokenType = FILTER_CONTENT_PAGE;
}
// TODO: given this is not really a "filter", this feels slightly misplaced here
else if(filtername == "sort")
{
if(!result.sortConditions.empty())
{
throw LooqsGeneralException("Two sort statements are illegal");
}
result.sortConditions = createSortConditions(value);
continue;
}
else if(filtername == "limit")
{
result.limit = value.toInt();
continue;
}
else
{
throw LooqsGeneralException("Unknown filter provided!");
}
result.addToken(Token(tokenType, value));
}
}
if(mergeLoneWords)
{
QString mergedLoneWords = loneWords.join(' ');
if(!mergedLoneWords.isEmpty())
{
result.addToken(Token(loneWordsTokenType, mergedLoneWords));
}
}
/* Add our default implicit AND boolean condition where appropriate */
QVector<Token> newTokens;
TokenType prevType = BOOL_AND;
int needsBoolean = FILTER_CONTENT | FILTER_PATH | NEGATION;
for(Token &t : result.tokens)
{
if(t.type == BRACKET_OPEN || t.type & needsBoolean)
{
if(!((prevType & BOOL) == BOOL) && !((prevType & NEGATION) == NEGATION) &&
!((prevType & BRACKET_OPEN) == BRACKET_OPEN))
{
newTokens.append(Token(BOOL_AND));
}
}
prevType = t.type;
newTokens.append(t);
}
result.tokens = newTokens;
bool contentsearch = result.hasContentSearch();
bool sortsForContent = std::any_of(result.sortConditions.begin(), result.sortConditions.end(),
[](SortCondition c) { return c.field == CONTENT_TEXT; });
if(!contentsearch && sortsForContent)
{
throw LooqsGeneralException("We cannot sort by text if we don't search for it");
}
return result;
}