"""add help articles table

Revision ID: add_help_articles_table
Revises: c94c2b2b9f2e
Create Date: 2024-12-19 10:00:00.000000

"""
from alembic import op
import sqlalchemy as sa
from sqlalchemy import text


# revision identifiers, used by Alembic.
revision = 'add_help_articles_table'
down_revision = 'c94c2b2b9f2e'
branch_labels = None
depends_on = None


def upgrade():
    conn = op.get_bind()
    result = conn.execute(text("""
        SELECT EXISTS (
            SELECT FROM information_schema.tables 
            WHERE table_name = 'help_articles'
        );
    """))
    exists = result.scalar()
    if not exists:
        op.create_table('help_articles',
            sa.Column('id', sa.Integer(), nullable=False),
            sa.Column('title', sa.String(length=200), nullable=False),
            sa.Column('category', sa.String(length=50), nullable=False),
            sa.Column('body', sa.Text(), nullable=False),
            sa.Column('created_at', sa.DateTime(), nullable=True),
            sa.Column('updated_at', sa.DateTime(), nullable=True),
            sa.Column('created_by', sa.Integer(), nullable=False),
            sa.Column('is_published', sa.Boolean(), nullable=True, server_default='true'),
            sa.Column('order_index', sa.Integer(), nullable=True, server_default='0'),
            sa.ForeignKeyConstraint(['created_by'], ['user.id'], ondelete='CASCADE'),
            sa.PrimaryKeyConstraint('id')
        )
        
        # Create indexes for better performance
        op.create_index('idx_help_articles_category', 'help_articles', ['category'])
        op.create_index('idx_help_articles_published', 'help_articles', ['is_published'])
        op.create_index('idx_help_articles_order', 'help_articles', ['order_index'])
        op.create_index('idx_help_articles_created_at', 'help_articles', ['created_at'])


def downgrade():
    op.drop_index('idx_help_articles_category', table_name='help_articles')
    op.drop_index('idx_help_articles_published', table_name='help_articles')
    op.drop_index('idx_help_articles_order', table_name='help_articles')
    op.drop_index('idx_help_articles_created_at', table_name='help_articles')
    op.drop_table('help_articles')