"""V30 业务接入与核算准备解耦；无默认回填。"""

from pathlib import Path

from alembic import op
from sqlalchemy import text

revision = "30c1d2e3f4a5"
down_revision = "29b0c1d2e3f4"
branch_labels = None
depends_on = None


def upgrade():
    script = Path(__file__).resolve().parents[3] / "db/migration/V30__tplus_business_sync.sql"
    for statement in script.read_text(encoding="utf-8").split(";\n"):
        sql = "\n".join(line for line in statement.splitlines() if not line.lstrip().startswith("--")).strip()
        if sql:
            op.get_bind().execute(text(sql))


def downgrade():
    connection = op.get_bind()
    for table, condition in (("tplus_business_documents", "1=1"), ("products", "product_category IS NULL"),
                             ("customers", "customer_type IS NULL"), ("business_items", "product_category IS NULL"),
                             ("shipments", "freight_amount IS NULL")):
        if connection.scalar(text(f"SELECT COUNT(*) FROM {table} WHERE {condition}")):
            raise RuntimeError("已有接入或待补资料，请关闭接入并回退兼容版本；不删除业务数据以降级结构")
    op.drop_table("tplus_business_documents")
    op.drop_table("tplus_business_sync_configs")
    for index in ("idx_tplus_source_heads_parent", "idx_tplus_source_heads_customer_date", "idx_tplus_source_heads_date"):
        op.drop_index(index, "tplus_source_heads")
    for column in ("source_parent_id", "source_customer_id", "source_date"):
        op.drop_column("tplus_source_heads", column)
    op.drop_column("businesses", "integration_json")
    for table, column, sql_type, default in (("products", "product_category", "VARCHAR(32)", ""),
          ("customers", "customer_type", "VARCHAR(32)", " DEFAULT 'personal'"),
          ("business_items", "product_category", "VARCHAR(32)", ""),
          ("shipments", "freight_amount", "DECIMAL(14,2)", " DEFAULT 0")):
        connection.execute(text(f"ALTER TABLE {table} MODIFY {column} {sql_type} NOT NULL{default}"))