UI: ConfRuleManager: Simplify free Rule Id handling

src/ui/3rdparty/sqlite/dbquery.cpp

@@ -88,7 +88,7 @@ bool DbQuery::executeOk()
     return ok;
 }
 
-int DbQuery::getFreeId(int minId, int maxId)
+int DbQuery::getFreeId(int maxId, int minId)
 {
     int resId = minId;
 

src/ui/3rdparty/sqlite/dbquery.h

@@ -27,7 +27,7 @@ public:
     QVariant execute(int resultCount = 1);
     bool executeOk();
 
-    int getFreeId(int minId, int maxId);
+    int getFreeId(int maxId, int minId = 1);
 
 protected:
     void setResult(bool v);

src/ui/conf/confmanager.cpp

@@ -34,7 +34,7 @@ namespace {
 
 const QLoggingCategory LC("conf");
 
-constexpr int DATABASE_USER_VERSION = 40;
+constexpr int DATABASE_USER_VERSION = 41;
 
 const char *const sqlSelectAddressGroups = "SELECT addr_group_id, include_all, exclude_all,"
                                            "    include_zones, exclude_zones,"

src/ui/conf/confrulemanager.cpp

@@ -30,16 +30,8 @@ const char *const sqlUpdateRule = "UPDATE rule"
                                   "    accept_zones = ?9, reject_zones = ?10, mod_time = ?11"
                                   "  WHERE rule_id = ?1;";
 
-const char *const sqlSelectMaxRuleId = "SELECT MAX(rule_id) FROM rule;";
+const char *const sqlSelectRuleIds = "SELECT rule_id FROM rule"
-
+                                     "  WHERE rule_id < ?1 ORDER BY rule_id;";
-const char *const sqlInsertFreeRuleId = "INSERT INTO rule_free(rule_id) VALUES(?1);";
-
-const char *const sqlDeleteFreeRuleId = "DELETE FROM rule_free"
-                                        "  WHERE rule_id = ("
-                                        "    SELECT MAX(rule_id) FROM rule_free"
-                                        "  ) RETURNING rule_id;";
-
-const char *const sqlDeleteFreeRuleIds = "DELETE FROM rule_free WHERE rule_id >= ?1;";
 
 const char *const sqlDeleteRule = "DELETE FROM rule WHERE rule_id = ?1;";
 
@@ -188,8 +180,10 @@ bool ConfRuleManager::addOrUpdateRule(Rule &rule)
 
     const bool isNew = (rule.ruleId == 0);
     if (isNew) {
-        // Get Rule Id from the free list
+        rule.ruleId = DbQuery(sqliteDb(), &ok)
-        rule.ruleId = getFreeRuleId(ok);
+                              .sql(sqlSelectRuleIds)
+                              .vars({ ConfUtil::ruleMaxCount() })
+                              .getFreeId(/*maxId=*/ConfUtil::ruleMaxCount() - 1);
     } else {
         updateDriverRuleFlag(rule.ruleId, rule.enabled);
     }
@@ -244,9 +238,6 @@ bool ConfRuleManager::deleteRule(int ruleId)
         // Delete the Preset Rule from Rules
         DbQuery(sqliteDb()).sql(sqlDeleteRuleSet).vars(vars).executeOk();
         DbQuery(sqliteDb()).sql(sqlDeleteRuleSetSub).vars(vars).executeOk();
-
-        // Put the Rule Id back to the free list
-        putFreeRuleId(ruleId);
     }
 
     commitTransaction(ok);
@@ -324,35 +315,6 @@ bool ConfRuleManager::updateDriverRuleFlag(int ruleId, bool enabled)
     return true;
 }
 
-int ConfRuleManager::getFreeRuleId(bool &ok)
-{
-    const int ruleId = DbQuery(sqliteDb()).sql(sqlDeleteFreeRuleId).execute().toInt();
-    if (ruleId > 0) {
-        return ruleId;
-    }
-
-    const int maxRuleId = DbQuery(sqliteDb()).sql(sqlSelectMaxRuleId).execute().toInt();
-
-    ok = (maxRuleId < ConfUtil::ruleMaxCount());
-
-    return 0;
-}
-
-void ConfRuleManager::putFreeRuleId(int ruleId)
-{
-    const QVariantList vars = { ruleId };
-
-    const int maxRuleId = DbQuery(sqliteDb()).sql(sqlSelectMaxRuleId).execute().toInt();
-
-    if (ruleId < maxRuleId) {
-        // Add the Rule Id to free list
-        DbQuery(sqliteDb()).sql(sqlInsertFreeRuleId).vars(vars).executeOk();
-    } else {
-        // Delete outdated free Rule Ids
-        DbQuery(sqliteDb()).sql(sqlDeleteFreeRuleIds).vars(vars).executeOk();
-    }
-}
-
 bool ConfRuleManager::beginTransaction()
 {
     return sqliteDb()->beginWriteTransaction();

src/ui/conf/confrulemanager.h

@@ -45,9 +45,6 @@ signals:
 private:
     bool updateDriverRuleFlag(int ruleId, bool enabled);
 
-    int getFreeRuleId(bool &ok);
-    void putFreeRuleId(int ruleId);
-
     bool beginTransaction();
     void commitTransaction(bool &ok);
 

src/ui/conf/confzonemanager.cpp

@@ -106,7 +106,7 @@ bool ConfZoneManager::addOrUpdateZone(Zone &zone)
         zone.zoneId = DbQuery(sqliteDb(), &ok)
                               .sql(sqlSelectZoneIds)
                               .vars({ ConfUtil::zoneMaxCount() })
-                              .getFreeId(/*minId=*/1, /*maxId=*/ConfUtil::zoneMaxCount() - 1);
+                              .getFreeId(/*maxId=*/ConfUtil::zoneMaxCount() - 1);
     } else {
         updateDriverZoneFlag(zone.zoneId, zone.enabled);
     }

src/ui/conf/migrations/1.sql

@@ -102,10 +102,6 @@ CREATE TABLE rule(
 
 CREATE INDEX rule_rule_type_name_idx ON rule(rule_type, lower(name));
 
-CREATE TABLE rule_free(
-  rule_id INTEGER PRIMARY KEY
-);
-
 CREATE TABLE rule_set(
   rule_set_id INTEGER PRIMARY KEY,
   rule_id INTEGER NOT NULL,