from alembic import op
import sqlalchemy as sa
from sqlalchemy.dialects import mysql
revision = '96c23dad405d'
down_revision = '59baf2338f8a'
branch_labels = None
depends_on = None

def upgrade() -> None:
    from sqlalchemy import inspect
    bind = op.get_bind()
    inspector = inspect(bind)
    tables = inspector.get_table_names()
    if 'system_settings' not in tables:
        op.create_table('system_settings', sa.Column('id', sa.Integer(), autoincrement=True, nullable=False), sa.Column('key', sa.String(length=100), nullable=False), sa.Column('value', sa.Text(), nullable=False), sa.Column('description', sa.Text(), nullable=True), sa.Column('updated_at', sa.DateTime(), nullable=False), sa.Column('updated_by_id', sa.Integer(), nullable=True), sa.ForeignKeyConstraint(['updated_by_id'], ['users.id']), sa.PrimaryKeyConstraint('id'))
        op.create_index(op.f('ix_system_settings_id'), 'system_settings', ['id'], unique=False)
        op.create_index(op.f('ix_system_settings_key'), 'system_settings', ['key'], unique=True)
    columns = [col['name'] for col in inspector.get_columns('users')]
    if 'currency' not in columns:
        op.add_column('users', sa.Column('currency', sa.String(length=3), nullable=False, server_default='VND'))

def downgrade() -> None:
    try:
        op.drop_column('users', 'currency')
    except Exception:
        pass
    op.drop_index(op.f('ix_system_settings_key'), table_name='system_settings')
    op.drop_index(op.f('ix_system_settings_id'), table_name='system_settings')
    op.drop_table('system_settings')