Library addition and loading

database.py

@@ -3,21 +3,22 @@
 import sqlite3
 import os
 
-
-class DatabaseFunctions:
+class DatabaseInit:
     def __init__(self, location_prefix):
         os.makedirs(location_prefix, exist_ok=True)
-        self.database_path = os.path.join(
-            location_prefix, 'Lector.db')
+        database_path = os.path.join(location_prefix, 'Lector.db')
 
-        self.database = sqlite3.connect(self.database_path)
-        if not os.path.exists(self.database_path):
+        if not os.path.exists(database_path):
+            self.database = sqlite3.connect(database_path)
             self.create_database()
+        else:
+            self.database = sqlite3.connect(database_path)
 
     def create_database(self):
         self.database.execute(
             "CREATE TABLE books \
-            (id INTEGER PRIMARY KEY, Name TEXT, Path TEXT, ISBN TEXT, Tags TEXT, CoverImage BLOB)")
+            (id INTEGER PRIMARY KEY, Title TEXT, Path TEXT, \
+            ISBN TEXT, Tags TEXT, Hash TEXT, CoverImage BLOB)")
         self.database.execute(
             "CREATE TABLE cache \
             (id INTEGER PRIMARY KEY, Name TEXT, Path TEXT, CachedDict BLOB)")
@@ -26,5 +27,91 @@ class DatabaseFunctions:
 
         self.database.commit()
 
-    def add_to_database(self, book_data, image_data):
-        pass
+
+class DatabaseFunctions:
+    def __init__(self, location_prefix):
+        database_path = os.path.join(location_prefix, 'Lector.db')
+        self.database = sqlite3.connect(database_path)
+
+    def add_to_database(self, book_data):
+        # book_data is expected to be a dictionary
+        # with keys corresponding to the book hash
+        # and corresponding items containing
+        # whatever else needs insertion
+        # Haha I said insertion
+
+        for i in book_data.items():
+            book_hash = i[0]
+            book_title = i[1]['title'].replace("'", "")
+            book_path = i[1]['path']
+            book_cover = i[1]['cover_image']
+            book_isbn = i[1]['isbn']
+
+            # Check if the file might not already be in the database
+            hash_from_database = self.fetch_data(
+                ('Title',),
+                'books',
+                {'Hash': book_hash},
+                'EQUALS',
+                True)
+
+            sql_command_add = (
+                "INSERT INTO books (Title,Path,ISBN,Hash,CoverImage) VALUES(?, ?, ?, ?, ?)")
+
+            # TODO
+            # This is a placeholder. You will need to generate book covers
+            # in case none are found
+            if not hash_from_database and book_cover:
+                self.database.execute(
+                    sql_command_add,
+                    [book_title, book_path, book_isbn, book_hash, sqlite3.Binary(book_cover)])
+
+        self.database.commit()
+
+    def fetch_data(self, columns, table, selection_criteria, equivalence, fetch_one=False):
+        # columns is a tuple that will be passed as a comma separated list
+        # table is a string that will be used as is
+        # selection_criteria is a dictionary which contains the name of a column linked
+        # to a corresponding value for selection
+
+        # Example:
+        # Name and AltName are expected to be the same
+        # sel_dict = {
+        #     'Name': 'sav',
+        #     'AltName': 'sav'
+        # }
+        # data = DatabaseFunctions().fetch_data(('Name',), 'books', sel_dict)
+        try:
+            column_list = ','.join(columns)
+            sql_command_fetch = f"SELECT {column_list} FROM {table}"
+            if selection_criteria:
+                sql_command_fetch += " WHERE"
+
+                if equivalence == 'EQUALS':
+                    for i in selection_criteria.keys():
+                        search_parameter = selection_criteria[i]
+                        sql_command_fetch += f" {i} = '{search_parameter}' OR"
+
+                elif equivalence == 'LIKE':
+                    for i in selection_criteria.keys():
+                        search_parameter = "'%" + selection_criteria[i] + "%'"
+                        sql_command_fetch += f" {i} LIKE {search_parameter} OR"
+
+                sql_command_fetch = sql_command_fetch[:-3]  # Truncate the last OR
+
+            # book data is returned as a list of tuples
+            book_data = self.database.execute(sql_command_fetch).fetchall()
+
+            if book_data:
+                # Because this is the result of a fetchall(), we need an
+                # ugly hack (tm) to get correct results
+                if fetch_one:
+                    return book_data[0][0]
+
+                return book_data
+            else:
+                return None
+
+        # except sqlite3.OperationalError:
+        except KeyError:
+            print('SQLite is in rebellion, Commander')