"""Add conversations and messages tables

Revision ID: add_conversations_tables
Revises: 2c5f57dddb78
Create Date: 2024-03-19 10:00:00.000000

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


# revision identifiers, used by Alembic.
revision = 'add_conversations_tables'
down_revision = '2c5f57dddb78'
branch_labels = None
depends_on = None


def upgrade():
    # Create conversation table first
    conn = op.get_bind()
    inspector = inspect(conn)
    tables = inspector.get_table_names()
    
    if 'conversation' not in tables:
        op.create_table('conversation',
            sa.Column('id', sa.Integer(), nullable=False),
            sa.Column('name', sa.String(length=100), nullable=False),
            sa.Column('description', sa.Text(), nullable=True),
            sa.Column('created_at', sa.DateTime(), nullable=True),
            sa.Column('created_by', sa.Integer(), nullable=False),
            sa.ForeignKeyConstraint(['created_by'], ['user.id'], ),
            sa.PrimaryKeyConstraint('id')
        )

    # Create conversation_members table
    conn = op.get_bind()
    inspector = inspect(conn)
    tables = inspector.get_table_names()
    
    if 'conversation_members' not in tables:
        op.create_table('conversation_members',
            sa.Column('conversation_id', sa.Integer(), nullable=False),
            sa.Column('user_id', sa.Integer(), nullable=False),
            sa.ForeignKeyConstraint(['conversation_id'], ['conversation.id'], ),
            sa.ForeignKeyConstraint(['user_id'], ['user.id'], ),
            sa.PrimaryKeyConstraint('conversation_id', 'user_id')
        )

    # Create message table
    conn = op.get_bind()
    inspector = inspect(conn)
    tables = inspector.get_table_names()
    
    if 'message' not in tables:
        op.create_table('message',
            sa.Column('id', sa.Integer(), nullable=False),
            sa.Column('content', sa.Text(), nullable=False),
            sa.Column('created_at', sa.DateTime(), nullable=True),
            sa.Column('conversation_id', sa.Integer(), nullable=False),
            sa.Column('user_id', sa.Integer(), nullable=False),
            sa.ForeignKeyConstraint(['conversation_id'], ['conversation.id'], ),
            sa.ForeignKeyConstraint(['user_id'], ['user.id'], ),
            sa.PrimaryKeyConstraint('id')
        )


def downgrade():
    # Drop tables in reverse order
    op.drop_table('message')
    op.drop_table('conversation_members')
    op.drop_table('conversation')