From a6ddcef0c06dc2ddb4ccc64b5204d9aece7699ab Mon Sep 17 00:00:00 2001
From: Albert S <mail@quitesimple.org>
Date: Sat, 4 Jun 2022 23:12:58 +0200
Subject: [PATCH] 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:'
---
 shared/looqsquery.cpp | 47 ++++++++++++++++++++++++++-----------------
 shared/looqsquery.h   |  9 +++++++++
 shared/token.h        | 15 +++++++-------
 3 files changed, 45 insertions(+), 26 deletions(-)

diff --git a/shared/looqsquery.cpp b/shared/looqsquery.cpp
index c702014..5da291c 100644
--- a/shared/looqsquery.cpp
+++ b/shared/looqsquery.cpp
@@ -220,19 +220,8 @@ LooqsQuery LooqsQuery::build(QString expression, TokenType loneWordsTokenType, b
 			{
 				throw LooqsGeneralException("Can't have two negations following each other");
 			}
-			if(!previousWasBool())
-			{
-				result.addToken(Token(BOOL_AND)); // Implicit and, our default operation
-			}
 			result.addToken(Token(NEGATION));
 		}
-		if(!result.tokens.isEmpty() && !previousWasBool() && !previousWas(NEGATION) && !previousWas(BRACKET_OPEN) &&
-		   bracket != ")")
-		{
-			// the current token isn't a negation, isn't a boolean. Thus, implicit AND is required
-			result.addToken(Token(BOOL_AND));
-		}
-
 		if(bracket != "")
 		{
 			if(bracket == "(")
@@ -259,7 +248,7 @@ LooqsQuery LooqsQuery::build(QString expression, TokenType loneWordsTokenType, b
 
 		if(filtername != "")
 		{
-			TokenType tokenType;
+			TokenType tokenType = WORD;
 			QString value = m.captured("innerargs");
 			if(value == "")
 			{
@@ -294,21 +283,21 @@ LooqsQuery LooqsQuery::build(QString expression, TokenType loneWordsTokenType, b
 			{
 				tokenType = FILTER_CONTENT_PAGE;
 			}
-			else if(filtername ==
-					"sort") // TODO: given this is not really a "filter", this feels slightly misplaced here
+			// 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");
 				}
-				// TODO: hack, since we are not a "filter", we must remove a preceeding (implicit) boolean
-				if((result.tokens.last().type & BOOL) == BOOL)
-				{
-					result.tokens.pop_back();
-				}
 				result.sortConditions = createSortConditions(value);
 				continue;
 			}
+			else if(filtername == "limit")
+			{
+				result.limit = value.toInt();
+				continue;
+			}
 			else
 			{
 				throw LooqsGeneralException("Unknown filter provided!");
@@ -326,6 +315,26 @@ LooqsQuery LooqsQuery::build(QString expression, TokenType loneWordsTokenType, b
 		}
 	}
 
+	/* 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; });
diff --git a/shared/looqsquery.h b/shared/looqsquery.h
index 115377e..2ec19a8 100644
--- a/shared/looqsquery.h
+++ b/shared/looqsquery.h
@@ -40,6 +40,7 @@ class LooqsQuery
 	/* Helper field to determine quertype as well as to quickly check what kind of filters etc.
 	 * are being used in this query*/
 	int tokensMask = 0;
+	int limit = -1;
 	QVector<Token> tokens;
 	QVector<SortCondition> sortConditions;
 	void addToken(Token t);
@@ -52,6 +53,14 @@ class LooqsQuery
 	{
 		return tokensMask;
 	}
+	int getLimit() const
+	{
+		return limit;
+	}
+	void setLimit(int limit)
+	{
+		this->limit = limit;
+	}
 	bool hasContentSearch();
 	bool hasPathSearch();
 
diff --git a/shared/token.h b/shared/token.h
index c8d2c21..84521d7 100644
--- a/shared/token.h
+++ b/shared/token.h
@@ -4,24 +4,25 @@
 
 enum TokenType
 {
-	WORD,
-	NEGATION = 2,
-	BOOL = 4,
+	WORD = 8,
+	NEGATION = 16,
+	BOOL = 32,
 	BOOL_AND,
 	BOOL_OR,
-	GROUP = 8,
+	GROUP = 64,
 	BRACKET_OPEN,
 	BRACKET_CLOSE,
-	SORT = 16,
-	FILTER_PATH = 32,
+	SORT = 128,
+	FILTER_PATH = 256,
 	FILTER_PATH_MTIME,
 	FILTER_PATH_CONTAINS,
 	FILTER_PATH_SIZE,
 	FILTER_PATH_ENDS,
 	FILTER_PATH_STARTS,
-	FILTER_CONTENT = 64,
+	FILTER_CONTENT = 512,
 	FILTER_CONTENT_CONTAINS,
 	FILTER_CONTENT_PAGE,
+	LIMIT = 1024
 };
 
 class Token