import sqlite3
from loguru import logger as log
from utils.slugify import slugify


def init_database(db_name='pipe_store.db'):
    conn = sqlite3.connect(db_name)
    cursor = conn.cursor()

    cursor.execute('''
        CREATE TABLE IF NOT EXISTS categories (
            id INTEGER PRIMARY KEY AUTOINCREMENT,
            name TEXT NOT NULL UNIQUE,
            description TEXT,
            parent_id INTEGER,
            image_path TEXT,
            created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
            FOREIGN KEY (parent_id) REFERENCES categories (id)
        )
    ''')

    cursor.execute('''
        CREATE TABLE IF NOT EXISTS products (
            id INTEGER PRIMARY KEY AUTOINCREMENT,
            name TEXT NOT NULL,
            description TEXT,
            category_id INTEGER NOT NULL,
            diameter INTEGER,
            wall_thickness REAL,
            length INTEGER,
            color TEXT,
            application_type TEXT, -- внутренняя/наружная
            stiffness_class TEXT, -- SN4, SN2 и т.д.
            image_path TEXT,
            slug TEXT,
            created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
            FOREIGN KEY (category_id) REFERENCES categories (id)
        )
    ''')

    cursor.execute('''
        CREATE TABLE IF NOT EXISTS filters (
            id INTEGER PRIMARY KEY AUTOINCREMENT,
            name TEXT NOT NULL,
            filter_key TEXT NOT NULL UNIQUE, -- ключ для фильтрации
            filter_type TEXT DEFAULT 'single' -- 'single' или 'multiple'
        )
    ''')

    cursor.execute('''
        CREATE TABLE IF NOT EXISTS product_filters (
            id INTEGER PRIMARY KEY AUTOINCREMENT,
            product_id INTEGER NOT NULL,
            filter_key TEXT NOT NULL,
            value TEXT NOT NULL,
            FOREIGN KEY (product_id) REFERENCES products (id),
            FOREIGN KEY (filter_key) REFERENCES filters (filter_key),
            UNIQUE(product_id, filter_key)
        )
    ''')
    
    cursor.execute('CREATE INDEX IF NOT EXISTS idx_products_category ON products(category_id)')
    cursor.execute('CREATE INDEX IF NOT EXISTS idx_products_diameter ON products(diameter)')
    cursor.execute('CREATE INDEX IF NOT EXISTS idx_products_length ON products(length)')
    cursor.execute('CREATE INDEX IF NOT EXISTS idx_product_filters_key_value ON product_filters(filter_key, value)')
    
    # Миграция: добавляем колонку slug, если её нет
    cursor.execute("PRAGMA table_info(products)")
    columns = {row[1] for row in cursor.fetchall()}
    if 'slug' not in columns:
        cursor.execute("ALTER TABLE products ADD COLUMN slug TEXT")
        log.info("Migration: added 'slug' column to products")

    # Миграция: переименовываем full_name → name
    cursor.execute("PRAGMA table_info(products)")
    columns = {row[1] for row in cursor.fetchall()}
    if 'full_name' in columns and 'name' not in columns:
        cursor.executescript('''
            PRAGMA foreign_keys=OFF;
            CREATE TABLE products_new (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                name TEXT NOT NULL,
                description TEXT,
                category_id INTEGER NOT NULL,
                diameter INTEGER,
                wall_thickness REAL,
                length INTEGER,
                color TEXT,
                application_type TEXT,
                stiffness_class TEXT,
                image_path TEXT,
                slug TEXT,
                created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
                FOREIGN KEY (category_id) REFERENCES categories (id)
            );
            INSERT INTO products_new (id, name, description, category_id, diameter, wall_thickness, length, color, application_type, stiffness_class, image_path, slug, created_at)
                SELECT id, full_name, description, category_id, diameter, wall_thickness, length, color, application_type, stiffness_class, image_path, slug, created_at FROM products;
            DROP TABLE products;
            ALTER TABLE products_new RENAME TO products;
            CREATE INDEX IF NOT EXISTS idx_products_category ON products(category_id);
            CREATE INDEX IF NOT EXISTS idx_products_diameter ON products(diameter);
            CREATE INDEX IF NOT EXISTS idx_products_length ON products(length);
        ''')
        log.info("Migrated products table: renamed 'full_name' → 'name'")
    
    # Миграция: заполняем slug для старых товаров
    cursor.execute("""
        SELECT p.id, p.name, p.diameter, p.wall_thickness, p.length,
               p.stiffness_class, p.application_type,
               pf.value as fitting_type
        FROM products p
        LEFT JOIN product_filters pf ON pf.product_id = p.id AND pf.filter_key = 'fitting_type'
        WHERE p.slug IS NULL OR p.slug = ''
    """)
    rows = cursor.fetchall()
    for row in rows:
        id_, name, diameter, wall_thickness, length, stiffness_class, application_type, fitting_type = row
        if fitting_type:
            slug_source = name
        else:
            slug_parts = [name]
            if stiffness_class:
                slug_parts.append(stiffness_class)
            if diameter:
                slug_parts.append(f"d{diameter}")
            if wall_thickness:
                slug_parts.append(f"stenka{int(wall_thickness)}")
            if length and length > 0:
                slug_parts.append(f"l{length}")
            slug_source = " ".join(slug_parts)
        slug = slugify(slug_source)
        cursor.execute("UPDATE products SET slug = ? WHERE id = ?", (slug, id_))
        log.info(f"Backfill slug for product {id_}: {slug}")
    
    conn.commit()
    conn.close()
    log.success("База данных успешно инициализирована!")