"""Workspace tenant integrity constraints.

Plan 4.3: Add tenant-bound foreign keys to workspace child tables.

- workspaces: UNIQUE (tenant_id, id)
- workspace_modules: FK (tenant_id, workspace_id) → workspaces (tenant_id, id)
- workspace_widgets: FK (tenant_id, workspace_id) → workspaces (tenant_id, id)
- workspace_users: FK (tenant_id, workspace_id) → workspaces (tenant_id, id)
- workspace_users: FK (tenant_id, user_id) → user_tenants (tenant_id, user_id)

Revision ID: 0096
Revises: 0095
"""

from __future__ import annotations

from alembic import op

revision = "0096"
down_revision = "0095"
branch_labels = None
depends_on = None


def upgrade() -> None:
    # 1. Add UNIQUE (tenant_id, id) on workspaces
    op.execute(
        "CREATE UNIQUE INDEX IF NOT EXISTS uq_workspaces_tenant_id "
        "ON workspaces (tenant_id, id)"
    )

    # 2. Drop existing FKs on workspace_modules (workspace_id → workspaces.id)
    #    and replace with tenant-bound FK
    op.execute("ALTER TABLE workspace_modules DROP CONSTRAINT IF EXISTS workspace_modules_workspace_id_fkey")
    op.execute(
        "ALTER TABLE workspace_modules "
        "ADD CONSTRAINT fk_wm_tenant_workspace "
        "FOREIGN KEY (tenant_id, workspace_id) "
        "REFERENCES workspaces (tenant_id, id) ON DELETE CASCADE"
    )

    # 3. Drop existing FK on workspace_widgets and replace with tenant-bound FK
    op.execute("ALTER TABLE workspace_widgets DROP CONSTRAINT IF EXISTS workspace_widgets_workspace_id_fkey")
    op.execute(
        "ALTER TABLE workspace_widgets "
        "ADD CONSTRAINT fk_ww_tenant_workspace "
        "FOREIGN KEY (tenant_id, workspace_id) "
        "REFERENCES workspaces (tenant_id, id) ON DELETE CASCADE"
    )

    # 4. Drop existing FK on workspace_users and replace with tenant-bound FK
    op.execute("ALTER TABLE workspace_users DROP CONSTRAINT IF EXISTS workspace_users_workspace_id_fkey")
    op.execute(
        "ALTER TABLE workspace_users "
        "ADD CONSTRAINT fk_wu_tenant_workspace "
        "FOREIGN KEY (tenant_id, workspace_id) "
        "REFERENCES workspaces (tenant_id, id) ON DELETE CASCADE"
    )

    # 5. Add FK on workspace_users (tenant_id, user_id) → user_tenants (tenant_id, user_id)
    op.execute(
        "ALTER TABLE workspace_users "
        "ADD CONSTRAINT fk_wu_tenant_user "
        "FOREIGN KEY (tenant_id, user_id) "
        "REFERENCES user_tenants (tenant_id, user_id) ON DELETE CASCADE"
    )


def downgrade() -> None:
    # Remove tenant-bound FKs, restore simple FKs
    op.execute("ALTER TABLE workspace_users DROP CONSTRAINT IF EXISTS fk_wu_tenant_user")
    op.execute("ALTER TABLE workspace_users DROP CONSTRAINT IF EXISTS fk_wu_tenant_workspace")
    op.execute(
        "ALTER TABLE workspace_users "
        "ADD CONSTRAINT workspace_users_workspace_id_fkey "
        "FOREIGN KEY (workspace_id) REFERENCES workspaces (id) ON DELETE CASCADE"
    )

    op.execute("ALTER TABLE workspace_widgets DROP CONSTRAINT IF EXISTS fk_ww_tenant_workspace")
    op.execute(
        "ALTER TABLE workspace_widgets "
        "ADD CONSTRAINT workspace_widgets_workspace_id_fkey "
        "FOREIGN KEY (workspace_id) REFERENCES workspaces (id) ON DELETE CASCADE"
    )

    op.execute("ALTER TABLE workspace_modules DROP CONSTRAINT IF EXISTS fk_wm_tenant_workspace")
    op.execute(
        "ALTER TABLE workspace_modules "
        "ADD CONSTRAINT workspace_modules_workspace_id_fkey "
        "FOREIGN KEY (workspace_id) REFERENCES workspaces (id) ON DELETE CASCADE"
    )

    op.execute("DROP INDEX IF EXISTS uq_workspaces_tenant_id")