Change: module structure to single file structure as professor requested for some reason...

exercises/python_basics/ej2/main.py

@@ -0,0 +1,300 @@
+from pathlib import Path
+from tkinter import Tk
+import sqlite3
+import csv
+import tkinter as tk
+from tkinter import ttk, messagebox
+from tkinter.scrolledtext import ScrolledText
+
+# --- CONSTANTS ------------------------------------------
+DATA_DIR = Path(__file__).parent / "data"
+CSV_PATH =  DATA_DIR / "books.csv"
+DB_PATH = DATA_DIR / "books.bd"
+
+# --- HELPER CLASSES -------------------------------------
+class FileReader:
+    _instance = None
+
+    def __new__(cls, *args, **kwargs):
+        if cls._instance is None:
+            cls._instance = super().__new__(cls)
+        return cls._instance
+
+    def __init__(self, delimiter=";"):
+        self.delimiter = delimiter
+
+    def read(self, file):
+        results = []
+        try:
+            with open(file, encoding="utf-8-sig") as f:
+                reader = csv.DictReader(f, delimiter=self.delimiter)
+                for row in reader:
+                    results.append(dict(row))
+        except Exception as e:
+            print(f"Error leyendo archivo: {e}")
+        return results
+
+class DBAttr:
+    def __init__(self, name, type_, modifier=""):
+        self.name = name
+        self.type_ = type_
+        self.modifier = modifier
+
+    def sql(self):
+        parts = [self.name, self.type_]
+        if self.modifier:
+            parts.append(self.modifier)
+        return " ".join(parts)
+
+class DBManager:
+    _instance = None
+    
+    def __new__(cls, *args, **kwargs):
+        if cls._instance is None:
+            cls._instance = super().__new__(cls)
+        return cls._instance
+    
+    def __init__(self, path):
+        self.path = Path(path)
+        self.conn = sqlite3.connect(self.path)
+        self.conn.row_factory = sqlite3.Row
+
+    def create_table(self, table_name, attributes: list[DBAttr]):
+        columns_sql = ",\n    ".join(attr.sql() for attr in attributes)
+
+        query = f"""
+        CREATE TABLE IF NOT EXISTS {table_name} (
+            {columns_sql}
+        );
+        """
+
+        try:
+            with self.conn:
+                self.conn.execute(query)
+        except Exception as e:
+            print("Error creating table:", e)
+
+    def get_all(self, table_name):
+        try:
+            cursor = self.conn.execute(f"SELECT * FROM {table_name};")
+            return [dict(row) for row in cursor.fetchall()]
+        except Exception as e:
+            print("Error selecting:", e)
+            return []
+
+    def get_by(self, table_name, column, value):
+        try:
+            query = f"SELECT * FROM {table_name} WHERE {column} = ?;"
+            cursor = self.conn.execute(query, (value,))
+            return [dict(row) for row in cursor.fetchall()]
+        except Exception as e:
+            print("Error selecting:", e)
+            return []
+
+    def insert(self, table_name, data: dict):
+        keys = ", ".join(data.keys())
+        placeholders = ", ".join("?" for _ in data)
+        values = tuple(data.values())
+
+        query = f"""
+        INSERT INTO {table_name} ({keys})
+        VALUES ({placeholders});
+        """
+
+        try:
+            with self.conn:
+                self.conn.execute(query, values)
+        except Exception as e:
+            print("Error inserting:", e)
+
+    def update(self, table_name, data: dict, where_column, where_value):
+        set_clause = ", ".join(f"{key} = ?" for key in data.keys())
+        values = list(data.values())
+        values.append(where_value)
+
+        query = f"""
+        UPDATE {table_name}
+        SET {set_clause}
+        WHERE {where_column} = ?;
+        """
+
+        try:
+            with self.conn:
+                self.conn.execute(query, tuple(values))
+        except Exception as e:
+            print("Error updating:", e)
+
+    def delete(self, table_name, where_column, where_value):
+        query = f"DELETE FROM {table_name} WHERE {where_column} = ?;"
+
+        try:
+            with self.conn:
+                self.conn.execute(query, (where_value,))
+        except Exception as e:
+            print("Error deleting:", e)
+
+    def exists(self, table_name, where_column, where_value):
+        query = f"SELECT 1 FROM {table_name} WHERE {where_column} = ? LIMIT 1;"
+
+        try:
+            cursor = self.conn.execute(query, (where_value,))
+            return cursor.fetchone() is not None
+        except Exception as e:
+            print("Error checking existence:", e)
+            return False
+
+    def count(self, table_name):
+        try:
+            cursor = self.conn.execute(f"SELECT COUNT(*) as total FROM {table_name};")
+            return cursor.fetchone()["total"]
+        except Exception as e:
+            print("Error counting:", e)
+            return 0
+
+    def close(self):
+        self.conn.close()
+
+class BooksUI():
+    def __init__(self, root, title = "AII"):
+        self.root = root
+        self.root.title(title)
+        self.root.geometry("900x600")
+                
+        # Menu Principal
+        self.menu = tk.Menu(self.root)
+        self.root.config(menu=self.menu)
+
+        # Menu Datos
+        datos_menu = tk.Menu(self.menu, tearoff=0)
+        datos_menu.add_command(label="Cargar", command=lambda: self.callback("cargar"))
+        datos_menu.add_separator()
+        datos_menu.add_command(label="Salir", command=self.root.quit)
+        self.menu.add_cascade(label="Datos", menu=datos_menu)
+
+        # Menu Listar
+        listar_menu = tk.Menu(self.menu, tearoff=0)
+        listar_menu.add_command(label="Completo", command=lambda: self.callback("listar_completo"))
+        listar_menu.add_command(label="Ordenado", command=lambda: self.callback("listar_ordenado"))
+        self.menu.add_cascade(label="Listar", menu=listar_menu)
+
+        # Menu Buscar
+        buscar_menu = tk.Menu(self.menu, tearoff=0)
+        buscar_menu.add_command(label="Título", command=lambda: self.callback("buscar_titulo"))
+        buscar_menu.add_command(label="Editorial", command=lambda: self.callback("buscar_editorial"))
+        self.menu.add_cascade(label="Buscar", menu=buscar_menu)
+
+        # Callback externo desde el punto de entrada
+        self.callback = None
+        
+    def show_list(self, books, fields, title="Listado"):
+        mw = tk.Toplevel(self.root)
+        mw.title(title)
+        listbox = tk.Listbox(mw, width=80, height=20)
+        listbox.pack(side="left", fill="both", expand=True)
+        scrollbar = tk.Scrollbar(mw)
+        scrollbar.pack(side="right", fill="y")
+        listbox.config(yscrollcommand=scrollbar.set)
+        scrollbar.config(command=listbox.yview)
+        
+        for book in books:
+            row = " | ".join(str(book[field]) for field in fields)
+            listbox.insert("end", row)
+            
+    def ask_text(self, label, callback):
+        mw = tk.Toplevel(self.root)
+        mw.title(label)
+        tk.Label(mw, text=label).pack(pady=5)
+        entry = ttk.Entry(mw)
+        entry.pack(pady=5)
+        ttk.Button(mw, text="Aceptar", command=
+                    lambda: [callback(entry.get()), mw.destroy()]).pack(pady=10)   
+    
+    def ask_spinbox(self, label, options, callback):
+        mw = tk.Toplevel(self.root)
+        mw.title(label)
+        tk.Label(mw, text=label).pack(pady=5)
+        spinbox = ttk.Spinbox(mw, values=options, state="readonly", width=40)
+        spinbox.pack(pady=5)
+        ttk.Button(mw, text="Aceptar", command=
+                    lambda: [callback(spinbox.get()), mw.destroy()]).pack(pady=10)
+        
+    def ask_radiobutton(self, label, options, callback):
+        mw = tk.Toplevel(self.root)
+        mw.title(label)
+        tk.Label(mw, text=label).pack(pady=5)
+        sv = tk.StringVar(value=options[0])
+        for option in options:
+            tk.Radiobutton(mw, text=option, variable=sv, value=option).pack(anchor="w")
+        ttk.Button(mw, text="Aceptar", command=
+                    lambda: [callback(sv.get()), mw.destroy()]).pack(pady=10)
+        
+    def info(slef, message):
+        messagebox.showinfo("Información", message) 
+
+# --- MAIN PROGRAM FUNCTIONS -----------------------------
+dbm = DBManager(DB_PATH)
+fr = FileReader()
+
+def create_tables():
+    book_attrs = [
+        DBAttr("isbn", "INTEGER", "PRIMARY KEY"),
+        DBAttr("title", "TEXT", "NOT NULL"),
+        DBAttr("author", "TEXT"),
+        DBAttr("year", "DATE"),
+        DBAttr("publisher", "TEXT")
+    ]
+    
+    dbm.create_table("books", book_attrs)
+
+def main():
+    create_tables()
+    root = Tk()
+    ui = BooksUI(root)
+    
+    def handle_action(action):
+        match(action):
+            case "cargar":
+                books = fr.read(CSV_PATH)
+                count = 0
+                for book in books:
+                    book["isbn"] = int(book["isbn"])
+                    if not dbm.exists("books", "isbn", book["isbn"]):
+                        dbm.insert("books", book)
+                        count += 1
+                ui.info(f"{count} libros almacenados.")  
+            case "listar_todo":
+                books = dbm.get_all("books")
+                ui.show_list(books, ["isbn", "title", "author", "year"])
+            case "listar_ordenado":
+                def sort(attr):
+                    books = dbm.get_all("books")
+                    def key_fn(x):
+                        v = x[attr]
+                        if isinstance(v, int):
+                            return v
+                        elif isinstance(v, str) and v.isdigit():
+                            return int(v)
+                        else:
+                            return float('inf')
+                    books.sort(key=key_fn)
+                    ui.show_list(books, ["isbn", "title", "author", "year"])
+                ui.ask_radiobutton("Ordenar por: ", ["isbn", "year"], sort)
+            case "buscar_titulo":
+                def search_title(title):
+                    books = [book for book in dbm.get_all("books") if title.lower() in book["title"].lower()]
+                    ui.show_list(books, ["isbn", "title", "author", "year"])
+                ui.ask_text("Buscar por título: ", search_title)
+            case "buscar_editorial":
+                publishers = list({book["publisher"] for book in dbm.get_all("books")})
+                publishers.sort()
+                def search_publisher(publisher):
+                    books = [book for book in dbm.get_all("books") if book["publisher"] == publisher]
+                    ui.show_list(books, ["title", "author", "publisher"])
+                ui.ask_spinbox("Selecciona editorial: ", publishers, search_publisher)
+    
+    ui.callback = handle_action
+    root.mainloop()
+    dbm.close()
+    
+if __name__ == "__main__":
+    main()