Models
======

The ``shares`` app has two models: the concrete asset type ``Share``
and its dividend records.

Share
-----

Concrete subclass of :class:`~richy.core.models.Item` -- ``Share``
joins the ``core_item`` table via Django multi-table inheritance, so
the ``symbol`` / ``type`` / ``is_discontinued`` fields come from
:class:`~richy.core.models.BaseItem` and the four boolean
``is_share`` / ``is_index`` / ``is_etf`` / ``is_coin`` methods
implement the polymorphic dispatch used across the app.

The ``update_cache`` override invalidates the share-specific
transaction-performance / profit-performance cache keys and
**re-warms them** by re-running ``Performance`` so the next request
doesn't have to pay the cache-miss cost.

.. autoclass:: richy.shares.models.Share
   :show-inheritance:

.. automethod:: richy.shares.models.Share.update_cache

Dividend
--------

A dividend record for a :class:`Share`. Inherits all fields from
:class:`~richy.core.models.BaseDividend` and adds only the ``share``
foreign key. Records are downloaded by
:meth:`~richy.core.scraper.Manager.get_dividends` (which wraps the
``rug`` library); shares with no dividends produce an empty list.

Field semantics:

- ``ex_date`` -- the first date on which a stock is traded without
  the right to receive the next dividend payment (equals the
  ``record_date`` since 2024).
- ``record_date`` -- the day a company finalizes which shareholders
  receive the dividend.
- ``payment_date`` -- the date the dividend is paid out.
- ``yield_value`` -- dividend in %.
- ``amount_value`` -- dividend as a value in currency.

.. autoclass:: richy.shares.models.Dividend
   :show-inheritance: