Anki Add-on: Set the number of new cards due in a specified deck based on how much time total you want to spend in review

anki_new_card_setter.py

import math
from aqt import mw
from aqt.qt import *

DECK_EXACT_NAME = "z"
TOTAL_MINUTES = 50

# TODO: I can get this stuff from existing information in DB
CARDS_PER_MINUTE = 11.5
REPS_PER_NEW_CARD = 2.5
RETENTION = 0.85

def get_new_card_setting():
	due_card_ids = mw.col.findCards('deck:{} -deck:{}::* is:due -is:suspended'.format(DECK_EXACT_NAME, DECK_EXACT_NAME))
	total_reps_you_can_do = TOTAL_MINUTES * CARDS_PER_MINUTE
	estimated_reps_for_review = int(len(due_card_ids) / RETENTION)
	reps_still_available = total_reps_you_can_do - estimated_reps_for_review

	new_card_setting = 0
	if reps_still_available > 0:
		new_card_setting = int(reps_still_available / REPS_PER_NEW_CARD)

	return new_card_setting

def set_new_cards_in_deck(deck, new_card_setting):
	deck_configuration = mw.col.decks.confForDid(deck['id'])
	deck_configuration['new']['perDay'] = new_card_setting
	# if we don't save both the deck and deck config,
	# there will be a mismatch between the two and anki will force a full sync
	mw.col.decks.save(deck)
	mw.col.decks.save(deck_configuration)

def set_autoadd_deck_totals(total_new_setting):
	autoadd_decks = [deck for deck in mw.col.decks.all() if '[autoadd]' in deck['name']]
	autoadd_per_deck = 0
	new_actually_available = len(mw.col.findNotes('deck:{} -deck:{}::* is:new -is:suspended'
		.format(DECK_EXACT_NAME, DECK_EXACT_NAME)))
	if total_new_setting > new_actually_available:
		autoadd_total = total_new_setting - new_actually_available
		non_empty_autoadd_deck_count = sum('EMPTY' not in s['name'] for s in autoadd_decks)
		autoadd_per_deck = math.ceil(autoadd_total / non_empty_autoadd_deck_count)

	# since all autoadd decks share the same options group, we only have to update one of them.
	set_new_cards_in_deck(autoadd_decks[0], autoadd_per_deck)

def recalculate():
	total_new_setting = get_new_card_setting()
	set_new_cards_in_deck(mw.col.decks.byName(DECK_EXACT_NAME), total_new_setting)
	set_autoadd_deck_totals(total_new_setting)
	# if we don't reset the view, the configuration change will not be immediately visible in the UI
	mw.reset()

recalculate_action = QAction("Recalculate new card setting", mw)
recalculate_action.triggered.connect(recalculate)
mw.form.menuTools.addAction(recalculate_action)