"""add tenant-bound one-time OnlyOffice sessions

Revision ID: 20260717_0027
Revises: 20260717_0026
Create Date: 2026-07-17 10:00:00
"""

from __future__ import annotations

from collections.abc import Sequence

import sqlalchemy as sa

from alembic import op

revision: str = "20260717_0027"
down_revision: str | None = "20260717_0026"
branch_labels: str | Sequence[str] | None = None
depends_on: str | Sequence[str] | None = None


def _require_postgresql() -> None:
    dialect_name = op.get_bind().dialect.name
    if dialect_name != "postgresql":
        raise RuntimeError(
            "20260717_0027 only supports PostgreSQL; "
            f"refusing to mutate {dialect_name} without transactional constraint DDL"
        )


def _require_empty_for_downgrade() -> None:
    count = int(
        op.get_bind().scalar(
            sa.text("SELECT COUNT(*) FROM knowledge_onlyoffice_sessions")
        )
        or 0
    )
    if count:
        raise RuntimeError(
            "cannot downgrade knowledge tenant security: OnlyOffice session evidence exists "
            f"(knowledge_onlyoffice_sessions={count})"
        )


def upgrade() -> None:
    _require_postgresql()
    op.create_table(
        "knowledge_onlyoffice_sessions",
        sa.Column("jti", sa.String(length=36), nullable=False),
        sa.Column("tenant_id", sa.String(length=64), nullable=False),
        sa.Column("resource_scope", sa.String(length=16), nullable=False),
        sa.Column("document_id", sa.String(length=64), nullable=False),
        sa.Column("document_key", sa.String(length=160), nullable=False),
        sa.Column("document_version", sa.Integer(), nullable=False),
        sa.Column("audience", sa.String(length=80), nullable=False),
        sa.Column("editable", sa.Boolean(), nullable=False),
        sa.Column("status", sa.String(length=16), nullable=False),
        sa.Column("created_by", sa.String(length=100), nullable=False),
        sa.Column("expires_at", sa.DateTime(timezone=True), nullable=False),
        sa.Column("claimed_at", sa.DateTime(timezone=True), nullable=True),
        sa.Column("consumed_at", sa.DateTime(timezone=True), nullable=True),
        sa.Column("failure_reason", sa.Text(), nullable=False),
        sa.Column(
            "created_at",
            sa.DateTime(timezone=True),
            nullable=False,
            server_default=sa.func.now(),
        ),
        sa.CheckConstraint(
            "resource_scope IN ('tenant', 'platform')",
            name="ck_knowledge_onlyoffice_sessions_scope",
        ),
        sa.CheckConstraint(
            "status IN ('active', 'processing', 'consumed', 'failed', 'revoked')",
            name="ck_knowledge_onlyoffice_sessions_status",
        ),
        sa.CheckConstraint(
            "tenant_id IS NOT NULL AND "
            "(resource_scope = 'tenant' OR "
            "(resource_scope = 'platform' AND editable = false))",
            name="ck_knowledge_onlyoffice_sessions_scope_tenant",
        ),
        sa.CheckConstraint(
            "(status = 'active' AND claimed_at IS NULL AND consumed_at IS NULL) OR "
            "(status IN ('processing', 'failed') AND claimed_at IS NOT NULL "
            "AND consumed_at IS NULL) OR "
            "(status = 'consumed' AND claimed_at IS NOT NULL AND consumed_at IS NOT NULL) OR "
            "(status = 'revoked' AND consumed_at IS NULL)",
            name="ck_knowledge_onlyoffice_sessions_lifecycle",
        ),
        sa.ForeignKeyConstraint(
            ["tenant_id"],
            ["tenants.tenant_id"],
            name="fk_knowledge_onlyoffice_sessions_tenant",
            ondelete="CASCADE",
        ),
        sa.PrimaryKeyConstraint("jti"),
    )
    op.create_index(
        "ix_knowledge_onlyoffice_sessions_tenant_document",
        "knowledge_onlyoffice_sessions",
        ["tenant_id", "document_id", "created_at"],
    )
    op.create_index(
        "ix_knowledge_onlyoffice_sessions_status_expiry",
        "knowledge_onlyoffice_sessions",
        ["status", "expires_at"],
    )


def downgrade() -> None:
    _require_postgresql()
    _require_empty_for_downgrade()
    op.drop_index(
        "ix_knowledge_onlyoffice_sessions_status_expiry",
        table_name="knowledge_onlyoffice_sessions",
    )
    op.drop_index(
        "ix_knowledge_onlyoffice_sessions_tenant_document",
        table_name="knowledge_onlyoffice_sessions",
    )
    op.drop_table("knowledge_onlyoffice_sessions")