"""Add Configuration and Business Policy tables (RMM-style policies).

Creates configurationpolicies, configurationpolicyactions, businesspolicies,
and businesspolicyitems. These back the DT-authored policy feature that is gated
by the computers_configpolicies_enabled setting; the tables land regardless so
the switch can be flipped without a schema change, and the downgrade drops all
four for a clean rollback of the whole scope.

Idempotent: each create_table is skipped when the table already exists (e.g. a
test DB built by db.create_all()).

Revision ID: computers0004policies
Revises: computers0003azurefields
"""
from alembic import op
import sqlalchemy as sa


revision = 'computers0004policies'
down_revision = 'computers0003azurefields'
branch_labels = None
depends_on = None


# TEXT rather than sa.JSON on purpose. MySQL 5.6 has no JSON type - it arrived
# in 5.7 - and this migration failed there with a bare syntax error near the
# word JSON. Every other JSON-bearing column in the product is TEXT for the same
# reason (guides.blocksjson, geenforce.manifestjson); the model reads and writes
# dicts through the JSONText type decorator, so nothing above the database
# changes.


def upgrade():
    bind = op.get_bind()
    insp = sa.inspect(bind)
    existing = set(insp.get_table_names())

    if 'configurationpolicies' not in existing:
        op.create_table(
            'configurationpolicies',
            sa.Column('configurationpolicyid', sa.Integer(), nullable=False),
            sa.Column('name', sa.String(length=150), nullable=False),
            sa.Column('description', sa.Text(), nullable=True),
            sa.Column('scopejson', sa.Text(), nullable=True),
            sa.Column('source', sa.String(length=50), nullable=False,
                      server_default='local'),
            sa.Column('createddate', sa.DateTime(), nullable=False),
            sa.Column('modifieddate', sa.DateTime(), nullable=False),
            sa.Column('isactive', sa.Boolean(), nullable=False,
                      server_default=sa.true()),
            sa.PrimaryKeyConstraint('configurationpolicyid'),
            sa.UniqueConstraint('name', name='uq_configurationpolicy_name'),
        )
        op.create_index('idx_configpolicy_source', 'configurationpolicies',
                        ['source'])
        op.create_index('idx_configpolicy_active', 'configurationpolicies',
                        ['isactive'])

    if 'configurationpolicyactions' not in existing:
        op.create_table(
            'configurationpolicyactions',
            sa.Column('configurationpolicyactionid', sa.Integer(),
                      nullable=False),
            sa.Column('configurationpolicyid', sa.Integer(), nullable=False),
            sa.Column('action', sa.String(length=100), nullable=False),
            sa.Column('mode', sa.String(length=20), nullable=False,
                      server_default='gate'),
            sa.Column('desiredstate', sa.Text(), nullable=True),
            sa.Column('params', sa.Text(), nullable=True),
            sa.Column('intervalminutes', sa.Integer(), nullable=True),
            sa.Column('sortorder', sa.Integer(), nullable=False,
                      server_default='0'),
            sa.Column('createddate', sa.DateTime(), nullable=False),
            sa.Column('modifieddate', sa.DateTime(), nullable=False),
            sa.Column('isactive', sa.Boolean(), nullable=False,
                      server_default=sa.true()),
            sa.ForeignKeyConstraint(
                ['configurationpolicyid'],
                ['configurationpolicies.configurationpolicyid'],
                ondelete='CASCADE'),
            sa.PrimaryKeyConstraint('configurationpolicyactionid'),
            sa.UniqueConstraint('configurationpolicyid', 'action',
                                name='uq_configpolicyaction'),
        )
        op.create_index('idx_configpolicyaction_policy',
                        'configurationpolicyactions',
                        ['configurationpolicyid'])

    if 'businesspolicies' not in existing:
        op.create_table(
            'businesspolicies',
            sa.Column('businesspolicyid', sa.Integer(), nullable=False),
            sa.Column('name', sa.String(length=150), nullable=False),
            sa.Column('description', sa.Text(), nullable=True),
            sa.Column('priority', sa.Integer(), nullable=False,
                      server_default='100'),
            sa.Column('source', sa.String(length=50), nullable=False,
                      server_default='local'),
            sa.Column('createddate', sa.DateTime(), nullable=False),
            sa.Column('modifieddate', sa.DateTime(), nullable=False),
            sa.Column('isactive', sa.Boolean(), nullable=False,
                      server_default=sa.true()),
            sa.PrimaryKeyConstraint('businesspolicyid'),
            sa.UniqueConstraint('name', name='uq_businesspolicy_name'),
        )
        op.create_index('idx_businesspolicy_priority', 'businesspolicies',
                        ['priority'])
        op.create_index('idx_businesspolicy_active', 'businesspolicies',
                        ['isactive'])

    if 'businesspolicyitems' not in existing:
        op.create_table(
            'businesspolicyitems',
            sa.Column('businesspolicyitemid', sa.Integer(), nullable=False),
            sa.Column('businesspolicyid', sa.Integer(), nullable=False),
            sa.Column('configurationpolicyid', sa.Integer(), nullable=False),
            sa.Column('sortorder', sa.Integer(), nullable=False,
                      server_default='0'),
            sa.Column('createddate', sa.DateTime(), nullable=False),
            sa.Column('modifieddate', sa.DateTime(), nullable=False),
            sa.Column('isactive', sa.Boolean(), nullable=False,
                      server_default=sa.true()),
            sa.ForeignKeyConstraint(
                ['businesspolicyid'], ['businesspolicies.businesspolicyid'],
                ondelete='CASCADE'),
            sa.ForeignKeyConstraint(
                ['configurationpolicyid'],
                ['configurationpolicies.configurationpolicyid'],
                ondelete='CASCADE'),
            sa.PrimaryKeyConstraint('businesspolicyitemid'),
            sa.UniqueConstraint('businesspolicyid', 'configurationpolicyid',
                                name='uq_businesspolicyitem'),
        )
        op.create_index('idx_bpitem_business', 'businesspolicyitems',
                        ['businesspolicyid'])
        op.create_index('idx_bpitem_config', 'businesspolicyitems',
                        ['configurationpolicyid'])


def downgrade():
    bind = op.get_bind()
    insp = sa.inspect(bind)
    existing = set(insp.get_table_names())

    if 'businesspolicyitems' in existing:
        op.drop_index('idx_bpitem_config', table_name='businesspolicyitems')
        op.drop_index('idx_bpitem_business', table_name='businesspolicyitems')
        op.drop_table('businesspolicyitems')
    if 'businesspolicies' in existing:
        op.drop_index('idx_businesspolicy_active', table_name='businesspolicies')
        op.drop_index('idx_businesspolicy_priority', table_name='businesspolicies')
        op.drop_table('businesspolicies')
    if 'configurationpolicyactions' in existing:
        op.drop_index('idx_configpolicyaction_policy',
                      table_name='configurationpolicyactions')
        op.drop_table('configurationpolicyactions')
    if 'configurationpolicies' in existing:
        op.drop_index('idx_configpolicy_active',
                      table_name='configurationpolicies')
        op.drop_index('idx_configpolicy_source',
                      table_name='configurationpolicies')
        op.drop_table('configurationpolicies')