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Friday, July 10, 2015
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It seems that :mod:`lino.modlib.excerpts` needs another subtle
feature.  Currently the system adminstrator can define several excerpt
types per model. In that case one of these is marked as *primary* and
possibly also *certifying*.  Now in Chatelet they want that the *main
template* of an immersion contract
(:class:`lino_welfare.modlib.immersion.models.Contract`) can *vary*
depending on some value of some field of the excerpt's owner (the
database object being printed).  Currently there is *one* primary
excerpt type per database model (which defines *one* main template).

Possible solutions:

- create a new database model, i.e. we would have two types of
  immersion contracts.

- Add a kind of locally configurable rule, e.g. a callable property of
  the :mod:`lino_welfare.modlib.integ` plugin::

    def get_contract_template(self, obj, ar):
        """Called when `template` field of excerpt type is empty."""
        return "Default.odt"
    
  which in Chatelet would become::

    def get_contract_template(self, obj, ar):
        assert isinstance(obj, rt.models.immersion.Contract)
        if obj.company is None:
            return "StageInterne.odt"
        return "StageForem.odt"