modbison/backend/alembic/versions/0008_add_chat_tables.py

"""add chat tables (conversations, messages, message_reports)

Revision ID: 0008_add_chat_tables
Revises: 0007_add_social_graph_tables
Create Date: 2026-09-15 00:00:00.000000

docs/planning/social.md US-4 / app/models/chat.py. Models + migration only
-- text filtering, rate limiting, and send/report/moderation endpoints live
in sibling tasks that depend on this one.
"""
from typing import Sequence, Union

from alembic import op
import sqlalchemy as sa
from sqlalchemy.dialects import postgresql

# revision identifiers, used by Alembic.
revision: str = "0008_add_chat_tables"
down_revision: Union[str, None] = "0007_add_social_graph_tables"
branch_labels: Union[str, Sequence[str], None] = None
depends_on: Union[str, Sequence[str], None] = None


def upgrade() -> None:
    message_report_status = postgresql.ENUM(
        "open", "resolved", "dismissed", name="message_report_status"
    )
    message_report_status.create(op.get_bind(), checkfirst=True)

    op.create_table(
        "conversations",
        sa.Column("id", sa.Integer(), primary_key=True),
        sa.Column(
            "user_a_id",
            sa.Integer(),
            sa.ForeignKey("users.id", ondelete="CASCADE"),
            nullable=False,
        ),
        sa.Column(
            "user_b_id",
            sa.Integer(),
            sa.ForeignKey("users.id", ondelete="CASCADE"),
            nullable=False,
        ),
        sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
        sa.Column("updated_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
        sa.UniqueConstraint("user_a_id", "user_b_id", name="uq_conversations_pair"),
        sa.CheckConstraint("user_a_id < user_b_id", name="ck_conversations_ordered_pair"),
    )
    op.create_index("ix_conversations_user_a_id", "conversations", ["user_a_id"])
    op.create_index("ix_conversations_user_b_id", "conversations", ["user_b_id"])

    op.create_table(
        "conversation_participants",
        sa.Column("id", sa.Integer(), primary_key=True),
        sa.Column(
            "conversation_id",
            sa.Integer(),
            sa.ForeignKey("conversations.id", ondelete="CASCADE"),
            nullable=False,
        ),
        sa.Column(
            "user_id",
            sa.Integer(),
            sa.ForeignKey("users.id", ondelete="CASCADE"),
            nullable=False,
        ),
        sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
        sa.UniqueConstraint(
            "conversation_id", "user_id", name="uq_conversation_participants_pair"
        ),
    )
    op.create_index(
        "ix_conversation_participants_conversation_id",
        "conversation_participants",
        ["conversation_id"],
    )
    op.create_index(
        "ix_conversation_participants_user_id", "conversation_participants", ["user_id"]
    )

    op.create_table(
        "messages",
        sa.Column("id", sa.Integer(), primary_key=True),
        sa.Column(
            "sender_id",
            sa.Integer(),
            sa.ForeignKey("users.id", ondelete="SET NULL"),
            nullable=True,
        ),
        sa.Column(
            "conversation_id",
            sa.Integer(),
            sa.ForeignKey("conversations.id", ondelete="CASCADE"),
            nullable=True,
        ),
        sa.Column(
            "world_id",
            sa.Integer(),
            sa.ForeignKey("worlds.id", ondelete="CASCADE"),
            nullable=True,
        ),
        sa.Column(
            "room_id",
            sa.Integer(),
            sa.ForeignKey("world_rooms.id", ondelete="CASCADE"),
            nullable=True,
        ),
        sa.Column("body", sa.Text(), nullable=False),
        sa.Column("filtered", sa.Boolean(), nullable=False, server_default="false"),
        sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
    )
    op.create_index("ix_messages_sender_id", "messages", ["sender_id"])
    op.create_index(
        "ix_messages_conversation_created", "messages", ["conversation_id", "created_at"]
    )
    op.create_index("ix_messages_world_created", "messages", ["world_id", "created_at"])

    op.create_table(
        "message_reports",
        sa.Column("id", sa.Integer(), primary_key=True),
        sa.Column(
            "message_id",
            sa.Integer(),
            sa.ForeignKey("messages.id", ondelete="SET NULL"),
            nullable=True,
        ),
        sa.Column(
            "reporter_id",
            sa.Integer(),
            sa.ForeignKey("users.id", ondelete="SET NULL"),
            nullable=True,
        ),
        sa.Column("reason", sa.Text(), nullable=False),
        sa.Column(
            "status",
            postgresql.ENUM(
                "open", "resolved", "dismissed", name="message_report_status", create_type=False
            ),
            nullable=False,
            server_default="open",
        ),
        sa.Column(
            "moderator_id",
            sa.Integer(),
            sa.ForeignKey("users.id", ondelete="SET NULL"),
            nullable=True,
        ),
        sa.Column("resolved_at", sa.DateTime(timezone=True), nullable=True),
        sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
    )
    op.create_index("ix_message_reports_message_id", "message_reports", ["message_id"])
    op.create_index("ix_message_reports_reporter_id", "message_reports", ["reporter_id"])
    op.create_index("ix_message_reports_moderator_id", "message_reports", ["moderator_id"])


def downgrade() -> None:
    op.drop_index("ix_message_reports_moderator_id", table_name="message_reports")
    op.drop_index("ix_message_reports_reporter_id", table_name="message_reports")
    op.drop_index("ix_message_reports_message_id", table_name="message_reports")
    op.drop_table("message_reports")

    op.drop_index("ix_messages_world_created", table_name="messages")
    op.drop_index("ix_messages_conversation_created", table_name="messages")
    op.drop_index("ix_messages_sender_id", table_name="messages")
    op.drop_table("messages")

    op.drop_index("ix_conversation_participants_user_id", table_name="conversation_participants")
    op.drop_index(
        "ix_conversation_participants_conversation_id", table_name="conversation_participants"
    )
    op.drop_table("conversation_participants")

    op.drop_index("ix_conversations_user_b_id", table_name="conversations")
    op.drop_index("ix_conversations_user_a_id", table_name="conversations")
    op.drop_table("conversations")

    postgresql.ENUM(name="message_report_status").drop(op.get_bind(), checkfirst=True)