"""清理多余产品分类脚本。

将数据库中多余的分类迁移到工业品(1)或日用品(2)，然后软删除多余分类。

运行方式: python -m backend.scripts.cleanup_categories
"""

from pathlib import Path
import sys

ROOT = Path(__file__).resolve().parents[2]
if str(ROOT) not in sys.path:
    sys.path.insert(0, str(ROOT))

from sqlalchemy import select, func

from backend.app.db import SessionLocal
from backend.app.models.business import Product, ProductCategory

# 保留的分类 ID
KEEP_IDS = {1, 2}

# 工业关键词：产品名包含这些词的归入工业品
INDUSTRY_KEYWORDS = ["布", "带", "胶", "板", "管", "钢", "铁", "铝", "铜", "塑", "膜", "网", "绳", "线", "丝", "棉", "纱"]


def classify_product(product_name: str) -> int:
    """根据产品名判断归入工业品(1)还是日用品(2)"""
    for kw in INDUSTRY_KEYWORDS:
        if kw in product_name:
            return 1
    return 2


def main():
    session = SessionLocal()
    try:
        # ========== Step 1: 查询当前状态 ==========
        print("=" * 60)
        print("产品分类清理脚本")
        print("=" * 60)

        categories = session.execute(
            select(ProductCategory).where(ProductCategory.deleted == 0).order_by(ProductCategory.id)
        ).scalars().all()

        print(f"\n当前分类列表（共 {len(categories)} 个）：")
        print("-" * 50)

        extra_categories = []
        for cat in categories:
            product_count = session.execute(
                select(func.count(Product.id)).where(
                    Product.category_id == cat.id,
                    Product.deleted == 0,
                )
            ).scalar() or 0

            tag = "✓ 保留" if cat.id in KEEP_IDS else "✗ 待删除"
            print(f"  ID={cat.id}  {cat.category_name:<12}  ({cat.category_code})  产品数: {product_count}  [{tag}]")

            if cat.id not in KEEP_IDS:
                extra_categories.append((cat, product_count))

        if not extra_categories:
            print("\n没有需要清理的多余分类。")
            return

        # 统计需要迁移的产品
        total_products_to_migrate = sum(count for _, count in extra_categories)
        print(f"\n需要迁移的产品总数: {total_products_to_migrate}")
        print(f"需要删除的分类数: {len(extra_categories)}")

        # 显示迁移计划
        print("\n迁移计划：")
        print("-" * 50)
        for cat, count in extra_categories:
            products = session.execute(
                select(Product).where(
                    Product.category_id == cat.id,
                    Product.deleted == 0,
                )
            ).scalars().all()

            industry_count = sum(1 for p in products if classify_product(p.product_name) == 1)
            daily_count = count - industry_count

            print(f"  分类「{cat.category_name}」({count}个产品):")
            print(f"    → 工业品: {industry_count} 个")
            print(f"    → 日用品: {daily_count} 个")

            for p in products:
                target = "工业品" if classify_product(p.product_name) == 1 else "日用品"
                print(f"      - {p.product_name} ({p.specification}) → {target}")

        # ========== Step 2: 确认 ==========
        print("\n" + "=" * 60)
        confirm = input("确认执行清理？(输入 yes 继续): ").strip()
        if confirm.lower() != "yes":
            print("已取消。")
            return

        # ========== Step 3: 执行迁移 ==========
        print("\n执行迁移...")
        migrated = 0
        for cat, count in extra_categories:
            products = session.execute(
                select(Product).where(
                    Product.category_id == cat.id,
                    Product.deleted == 0,
                )
            ).scalars().all()

            for p in products:
                target_id = classify_product(p.product_name)
                target_name = "工业品" if target_id == 1 else "日用品"
                p.category_id = target_id
                p.category = target_name
                migrated += 1
                print(f"  迁移: {p.product_name} → {target_name}")

        # ========== Step 4: 软删除多余分类 ==========
        print("\n删除多余分类...")
        deleted = 0
        for cat, _ in extra_categories:
            cat.deleted = 1
            deleted += 1
            print(f"  删除: {cat.category_name}")

        session.commit()

        # ========== Step 5: 验证 ==========
        print("\n" + "=" * 60)
        print("清理完成！验证结果：")

        remaining = session.execute(
            select(ProductCategory).where(ProductCategory.deleted == 0).order_by(ProductCategory.id)
        ).scalars().all()

        print(f"剩余分类数: {len(remaining)}")
        for cat in remaining:
            product_count = session.execute(
                select(func.count(Product.id)).where(
                    Product.category_id == cat.id,
                    Product.deleted == 0,
                )
            ).scalar() or 0
            print(f"  ID={cat.id}  {cat.category_name}  产品数: {product_count}")

        print(f"\n共迁移 {migrated} 个产品，删除 {deleted} 个分类。")

    finally:
        session.close()


if __name__ == "__main__":
    main()