# place me int filter_plugins dir next to your playbook

from __future__ import (absolute_import, division, print_function)
__metaclass__ = type

from ansible.errors import AnsibleError, AnsibleFilterError
from ansible.utils.display import Display

display = Display()

try:
    import _jsonnet
    HAS_LIB = True
except ImportError:
    HAS_LIB = False

def jsonnet_mixin(data, mixin):
    '''Evaluates Jsonnet '+ mixin' for a given input. 

    
    Example:
    - debug: msg="{{ '{a: 10}' | jsonnet_mixin('{b: self.a}') }}"
    '''
    if not HAS_LIB:
        raise AnsibleError('You need to install "jsonnet" from pypi')

    try:
        return _jsonnet.evaluate_snippet("filter_input", data + '+' + mixin)
    except Exception as e:
        # For older jmespath, we can get ValueError and TypeError without much info.
        raise AnsibleFilterError('Error in jsonnet_mixing filter plugin:\n%s' % e)


class FilterModule(object):
    ''' Query filter '''

    def filters(self):
        return {
            'jsonnet_mixin': jsonnet_mixin
        }