import lxml.etree as et
from opimodel import rules, colors
[docs]class OpiRule(object):
def __init__(self, color_renderer):
self._color = color_renderer
[docs] def render(self, widget_node, tag_name, rule_list):
if rule_list:
rules_node = et.SubElement(widget_node, tag_name)
for rule_model in rule_list:
self._render_one(rules_node, rule_model)
def _render_one(self, rules_node, rule_model):
self.rule_node = et.SubElement(rules_node, 'rule')
self.rule_node.set('prop_id', rule_model.get_prop_id())
self.rule_node.set('name', rule_model.get_name())
if isinstance(rule_model, rules.BetweenRule):
self._render_between(rule_model)
elif isinstance(rule_model, rules.GreaterThanRule):
self._render_greater_than(rule_model)
elif isinstance(rule_model, rules.SelectionRule):
self._render_selection(rule_model)
def _render_between(self, rule_model):
""" Write the between rule:
true iff a < p < b
as
true if p > a && p < b
false otherwise
The inequalities are replaced by p >= a and p <= b respectively if
min_equals or max_equals are True
"""
min_rule = 'pv0 {} {}'.format(
">=" if rule_model._min_equals else ">", rule_model._min)
max_rule = 'pv0 {} {}'.format(
"<=" if rule_model._max_equals else "<", rule_model._max)
pv_node = et.SubElement(self.rule_node, 'pv')
pv_node.set('trig', 'true')
pv_node.text = rule_model._pv
exp_node1 = et.SubElement(self.rule_node, 'exp')
exp_node1.set('bool_exp', '{} && {}'.format(min_rule, max_rule))
val_node1 = et.SubElement(exp_node1, 'value')
val_node1.text = 'true'
exp_node2 = et.SubElement(self.rule_node, 'exp')
exp_node2.set('bool_exp', 'true')
val_node2 = et.SubElement(exp_node2, 'value')
val_node2.text = 'false'
def _render_greater_than(self, rule_model):
pv_node = et.SubElement(self.rule_node, 'pv')
pv_node.set('trig', 'true')
pv_node.text = rule_model._pv
exp_node1 = et.SubElement(self.rule_node, 'exp')
exp_node1.set('bool_exp', 'pv0 > {}'.format(rule_model._threshold))
val_node1 = et.SubElement(exp_node1, 'value')
val_node1.text = 'true'
exp_node2 = et.SubElement(self.rule_node, 'exp')
exp_node2.set('bool_exp', 'true')
val_node2 = et.SubElement(exp_node2, 'value')
val_node2.text = 'false'
def _render_selection(self, rule_model):
pv_node = et.SubElement(self.rule_node, 'pv')
pv_node.set('trig', 'true')
pv_node.text = rule_model._pv
for (pv_val, prop_val) in rule_model._options:
exp_node = et.SubElement(self.rule_node, 'exp')
exp_node.set('bool_exp', '{} == {}'.format(rule_model._var, pv_val))
if isinstance(prop_val, colors.Color):
self._color.render(exp_node, 'value', prop_val)
else:
val_node = et.SubElement(exp_node, 'value')
val_node.text = str(prop_val)