"""add ticket_number to ticket

Revision ID: 20251208_add_ticket_number_to_ticket
Revises: 20251208_add_contact_person_and_phone_to_ticket
Create Date: 2025-12-08 11:35:00.000000

"""
from alembic import op
import sqlalchemy as sa
from sqlalchemy import text
from sqlalchemy.engine import reflection


# revision identifiers, used by Alembic.
revision = '20251208_add_ticket_number_to_ticket'
down_revision = '20251208_add_contact_person_and_phone_to_ticket'
branch_labels = None
depends_on = None


def upgrade():
    # ### commands auto generated by Alembic - please adjust! ###
    # 检查列是否已存在
    bind = op.get_bind()
    inspector = reflection.Inspector.from_engine(bind)
    columns = inspector.get_columns('ticket')
    column_names = [column['name'] for column in columns]
    
    # 只有当列不存在时才添加
    if 'ticket_number' not in column_names:
        with op.batch_alter_table('ticket', schema=None) as batch_op:
            batch_op.add_column(sa.Column('ticket_number', sa.String(length=32), nullable=True))
            batch_op.create_unique_constraint('uq_ticket_ticket_number', ['ticket_number'])

        # 为现有记录生成工单编号
        connection = op.get_bind()
        result = connection.execute(text("SELECT ticket_id FROM ticket WHERE ticket_number IS NULL"))
        ticket_ids = [row[0] for row in result]
        
        for ticket_id in ticket_ids:
            # 生成工单编号
            import datetime
            import random
            date_str = datetime.datetime.now().strftime('%Y%m%d')
            random_str = str(random.randint(1000, 9999))
            ticket_number = f"TKT{date_str}{random_str}"
            
            # 更新记录
            connection.execute(
                text("UPDATE ticket SET ticket_number = :ticket_number WHERE ticket_id = :ticket_id"),
                {"ticket_number": ticket_number, "ticket_id": ticket_id}
            )
        
        # 设置字段为非空
        with op.batch_alter_table('ticket', schema=None) as batch_op:
            batch_op.alter_column('ticket_number', nullable=False)
    # ### end Alembic commands ###


def downgrade():
    # ### commands auto generated by Alembic - please adjust! ###
    # 检查列是否已存在
    bind = op.get_bind()
    inspector = reflection.Inspector.from_engine(bind)
    columns = inspector.get_columns('ticket')
    column_names = [column['name'] for column in columns]
    
    # 只有当列存在时才删除
    if 'ticket_number' in column_names:
        with op.batch_alter_table('ticket', schema=None) as batch_op:
            batch_op.drop_constraint('uq_ticket_ticket_number', type_='unique')
            batch_op.drop_column('ticket_number')
    # ### end Alembic commands ###