Begin implementing meters

allzweckmesser/meters.py

 #!/usr/bin/env python3
 # -*- coding: utf-8 -*-
 
-ALL_METERS = []
+import re
+
+from .model import Reading
+
+
+def caesurae_together(positions, reward):
+    def get_reward(meter: Meter, reading: Reading):
+        # TODO: Check if caesurae occur.
+        return reward
+    return get_reward
+
+
+def bridge(position, reward):
+    def get_reward(meter: Meter, reading: Reading):
+        # TODO: Check if bridge occurs.
+        return reward
+    return get_reward
+
+
+class Meter:
+
+    def __init__(self, name: str, schema: str, conditions: list = None,
+                 short_name: str = None):
+        self.name = name
+        self.schema = schema
+        self.conditions = ([cond.__get__(self) for cond in conditions]
+                           if conditions else [])
+        self.short_name = short_name
+
+    def match_reading(self, reading: Reading):
+        return re.match(self.schema, reading.get_syllable_schema())
+
+    def get_rewards(self, reading: Reading):
+        return sum(cond(reading) for cond in self.conditions)
+
+
+ALL_METERS = [
+    Meter(
+        'Catalectic Dactylic Hexameter',
+        r'(–)(⏑⏑|–)(–)(⏑⏑|–)(–)(⏑⏑|–)(–)(⏑⏑|–)(–)(⏑⏑|–)(⏑|–)',
+        phenomena={
+            caesurae_together([('mora', 6, 'Trithemimeral'),
+                               ('mora', 14, 'Hephthemimeral')], 2),
+            caesurae_together([('mora', 10, 'Penthemimeral')], 1),
+            caesurae_together([('mora', 16, 'Bucolic Diaeresis')], 1),
+            bridge(('mora', 15, 'Hermann’s Bridge'), 1)
+        },
+        short_name='6da‸'
+    ),
+    Meter(
+        'Iambic Trimeter',
+        r'(⏑|⏑⏑|–)(⏑⏑|–)(⏑)(⏑⏑|–)(⏑|⏑⏑|–)(⏑⏑|–)(⏑)(⏑⏑|–)(⏑|⏑⏑|–)(⏑⏑|–)(⏑)(⏑|–)',
+        phenomena={
+            caesurae_together([('element', 4, 'After fourth element')], 1),
+            caesurae_together([('element', 8, 'After eighth element')], 1),
+        },
+        short_name='3ia'
+    ),
+]