"""Add history management fields to summaries

Revision ID: add_history_fields_001
Revises: 
Create Date: 2025-08-26 21:50:00.000000

"""
from alembic import op
import sqlalchemy as sa
from sqlalchemy.dialects import sqlite

# revision identifiers, used by Alembic.
revision = 'add_history_fields_001'
down_revision = None
branch_labels = None
depends_on = None


def upgrade() -> None:
    # Add new columns to summaries table
    with op.batch_alter_table('summaries', schema=None) as batch_op:
        batch_op.add_column(sa.Column('is_starred', sa.Boolean(), nullable=True))
        batch_op.add_column(sa.Column('notes', sa.Text(), nullable=True))
        batch_op.add_column(sa.Column('tags', sa.JSON(), nullable=True))
        batch_op.add_column(sa.Column('shared_token', sa.String(64), nullable=True))
        batch_op.add_column(sa.Column('is_public', sa.Boolean(), nullable=True))
        batch_op.add_column(sa.Column('view_count', sa.Integer(), nullable=True))
        
        # Add indexes
        batch_op.create_index('idx_is_starred', ['is_starred'])
        batch_op.create_index('idx_shared_token', ['shared_token'], unique=True)
    
    # Create composite indexes
    op.create_index('idx_user_starred', 'summaries', ['user_id', 'is_starred'])
    op.create_index('idx_user_created', 'summaries', ['user_id', 'created_at'])
    
    # Set default values for existing rows
    op.execute("""
        UPDATE summaries 
        SET is_starred = 0, 
            is_public = 0, 
            view_count = 0
        WHERE is_starred IS NULL
    """)


def downgrade() -> None:
    # Remove composite indexes first
    op.drop_index('idx_user_created', table_name='summaries')
    op.drop_index('idx_user_starred', table_name='summaries')
    
    # Remove columns and indexes
    with op.batch_alter_table('summaries', schema=None) as batch_op:
        batch_op.drop_index('idx_shared_token')
        batch_op.drop_index('idx_is_starred')
        batch_op.drop_column('view_count')
        batch_op.drop_column('is_public')
        batch_op.drop_column('shared_token')
        batch_op.drop_column('tags')
        batch_op.drop_column('notes')
        batch_op.drop_column('is_starred')