match_num now loaded from database

and --keep-db deprecated in favour of --new-db (harder for me to fu*k up)

src/database.py

@@ -5,7 +5,7 @@ class Database:
     def __init__(self, args):
         filename = ":memory:" if args.db is None else args.db
 
-        if not args.keep_db and os.path.exists(filename):
+        if args.new_db and os.path.exists(filename):
             os.remove(filename)
 
         self.new = not os.path.exists(filename)

src/match_store.py

@@ -9,7 +9,6 @@ class MatchStore:
     def __init__(self, args, db):
         self.db = db
         self.dispersions = {}
-        self.match_num = 0
 
 
         self.db.init("""CREATE TABLE Colocations (
@@ -51,6 +50,8 @@ class MatchStore:
         self.db.init("CREATE INDEX col_r ON Representations (colocation_id)")
         self.db.init("CREATE INDEX disp_key ON Dispersions (structure_id, component_id, lemma)")
 
+        match_num = self.db.execute("SELECT MAX(match_id) FROM Matches").fetchone()[0]
+        self.match_num = 0 if match_num is None else match_num + 1
     def _add_match(self, key, structure, match):
         structure_id, key_str = key[0], str(key[1:])
         cid = self.db.execute("SELECT colocation_id FROM Colocations WHERE key=? AND structure_id=?",

src/wani.py

@@ -125,8 +125,8 @@ if __name__ == '__main__':
 
     parser.add_argument('--db',
                         help="Database file to use (instead of memory)", default=None)
-    parser.add_argument('--keep-db',
-                        help="Does not recreate new database file", action='store_true')
+    parser.add_argument('--new-db',
+                        help="Writes over database file, if there exists one", action='store_true')
 
     parser.add_argument('--pc-tag',
                         help='Tag for separators, usually pc or c', default="pc")