commit 1692a5b23b99dae06f27aa50bebadeaf5268105a
Author: Juhani Haverinen <juhani.haverinen@gmail.com>
Date:   Wed Aug 24 15:12:52 2016 +0300

    First commit

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..516a4ad
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,4 @@
+*.zip
+lukkari.py
+__pycache__
+*.pyc
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..4d886ea
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,16 @@
+all: lukkari.py
+
+lukkari.py: lukkari/*.py
+	zip --quiet lukkari lukkari/*.py
+	zip --quiet --junk-paths lukkari lukkari/__main__.py
+	echo '#!/usr/bin/env python3' > lukkari.py
+	cat lukkari.zip >> lukkari.py
+	rm lukkari.zip
+	chmod +x lukkari.py
+
+.PHONY: all clean
+
+clean:
+	find . -name "*.pyc" -delete
+	find . -name "__pycache__" -delete
+	rm lukkari.zip lukkari.py || true
diff --git a/lukkari/__init__.py b/lukkari/__init__.py
new file mode 100644
index 0000000..87d5e51
--- /dev/null
+++ b/lukkari/__init__.py
@@ -0,0 +1,69 @@
+import datetime
+import sys
+import os.path
+from . import check_date
+from . import daterange
+from . import generate_timetable
+from . import parse_coursefile
+
+def parse_date(text):
+	split = text.split('-')
+	assert(len(split) == 3)
+	return tuple(map(int, split))
+
+def main():
+	if len(sys.argv) == 2:
+		year, week, day = datetime.date.today().isocalendar()
+		if day >= 6: # on weekend, show next week
+			year, week, day = (datetime.date.today() + datetime.timedelta(2)).isocalendar()
+		dates = daterange.week(year, week)
+		filename = sys.argv[1]
+	elif len(sys.argv) == 3:
+		date = parse_date(sys.argv[1])
+		dates = daterange.between(date, date)
+		filename = sys.argv[2]
+	elif len(sys.argv) == 4:
+		start = parse_date(sys.argv[1])
+		end = parse_date(sys.argv[2])
+		dates = daterange.between(start, end)
+		filename = sys.argv[3]
+	else:
+		print('%s [start [end]] file' % (os.path.basename(sys.argv[0])))
+		print('start and end are in yyyy-mm-dd format')
+		sys.exit(1)
+
+	with open(filename, 'r') as f:
+		courses_parsed = parse_coursefile.parse(f.read())
+
+	courses = []
+	for name, info, parsed_filter in courses_parsed:
+		date_filter = check_date.compile(parsed_filter)
+		courses.append((name, info, date_filter))
+	
+	timetable = generate_timetable.generate_timetable(dates, courses)
+
+	timetable_by_date = []
+	current_date = None
+	current_date_entries = []
+	for date, name, info in timetable:
+		if current_date is None:
+			current_date = date
+
+		if date == current_date:
+			current_date_entries.append((name, info))
+		else:
+			timetable_by_date.append((current_date, current_date_entries))
+			current_date = date
+			current_date_entries = []
+			current_date_entries.append((name, info))
+	
+	if current_date is not None and current_date_entries != []:
+		timetable_by_date.append((current_date, current_date_entries))
+	
+	print(dates)
+	print()
+
+	for date, entries in timetable_by_date:
+		print(date)
+		for name, info in entries:
+			print('\t%s: %s' % (name, info))
diff --git a/lukkari/__main__.py b/lukkari/__main__.py
new file mode 100644
index 0000000..30305f6
--- /dev/null
+++ b/lukkari/__main__.py
@@ -0,0 +1,3 @@
+import lukkari
+if __name__ == '__main__':
+	lukkari.main()
diff --git a/lukkari/check_date.py b/lukkari/check_date.py
new file mode 100644
index 0000000..e18cdf0
--- /dev/null
+++ b/lukkari/check_date.py
@@ -0,0 +1,94 @@
+import enum
+from . import daterange
+
+class Filters(enum.Enum):
+	in_date_range, is_weekday = range(2)
+
+class Conjunctions(enum.Enum):
+	all, any, none, implies = range(4)
+
+def compile(parsed):
+	assert(len(parsed) >= 1)
+	function, *parameters = parsed
+
+	assert(function in ['date', 'week', 'weekday', 'and', 'or', 'not', 'if'])
+
+	if function == 'date':
+		if len(parameters) == 1:
+			start, = parameters
+			end = start
+		else:
+			assert(len(parameters) == 2)
+			start, end = parameters
+
+		date_range = daterange.between(start, end)
+		return (Filters.in_date_range, date_range)
+
+	elif function == 'week':
+		if len(parameters) > 1:
+			return (Conjunctions.any, *[compile(('week', week)) for week in parameters])
+		else:
+			assert(len(parameters) == 1)
+			week_data, = parameters
+			year, week = week_data
+
+		date_range = daterange.week(year, week)
+		return (Filters.in_date_range, date_range)
+
+	elif function == 'weekday':
+		if len(parameters) > 1:
+			return (Conjunctions.any, *[compile(('weekday', weekday)) for weekday in parameters])
+		else:
+			assert(len(parameters) == 1)
+			weekday, = parameters
+
+		return (Filters.is_weekday, weekday)
+
+	elif function == 'and':
+		return (Conjunctions.all, *[compile(parameter) for parameter in parameters])
+
+	elif function == 'or':
+		return (Conjunctions.any, *[compile(parameter) for parameter in parameters])
+
+	elif function == 'not':
+		return (Conjunctions.none, *[compile(parameter) for parameter in parameters])
+
+	elif function == 'if':
+		assert(len(parameters) == 2)
+		condition, then = parameters
+		return (Conjunctions.implies, compile(condition), compile(then))
+
+def check_day_match(day, date_filter):
+	assert(len(date_filter) >= 1)
+	function, *parameters = date_filter
+
+	assert(function in Filters or function in Conjunctions)
+	if function == Conjunctions.implies:
+		assert(len(parameters) == 2)
+	elif function in [Filters.in_date_range, Filters.is_weekday]:
+		assert(len(parameters) == 1)
+	else:
+		assert(function in [Conjunctions.all, Conjunctions.any, Conjunctions.none])
+
+	if function == Conjunctions.all:
+		return all(map(lambda parameter: check_day_match(day, parameter), parameters))
+
+	elif function == Conjunctions.any:
+		return any(map(lambda parameter: check_day_match(day, parameter), parameters))
+
+	elif function == Conjunctions.implies:
+		left, right = parameters
+		left_truth = check_day_match(day, left)
+		right_truth = check_day_match(day, right)
+		return left_truth and right_truth or not left_truth
+
+	elif function == Conjunctions.none:
+		return not any(map(lambda parameter: check_day_match(day, parameter), parameters))
+
+	elif function == Filters.in_date_range:
+		date_range, = parameters
+		return day in date_range
+
+	elif function == Filters.is_weekday:
+		weekday, = parameters
+		return day.isoweekday() == weekday
diff --git a/lukkari/daterange.py b/lukkari/daterange.py
new file mode 100644
index 0000000..8500bc2
--- /dev/null
+++ b/lukkari/daterange.py
@@ -0,0 +1,67 @@
+import datetime
+
+class Daterange:
+	def __init__(self, start, length):
+		self.start = start
+		self.length = length
+
+	def range(self):
+		end = self.start + self.length - datetime.timedelta(1)
+		return (self.start, end)
+
+	def __contains__(self, day):
+		delta = day - self.start
+		return datetime.timedelta(0) <= delta and delta < self.length
+
+	def overlaps(self, other):
+		if other.start < self.start:
+			return other.overlaps(self)
+
+		assert(self.start <= other.start)
+		return other.start < self.start + self.length
+
+	def __repr__(self):
+		return 'Daterange(%s, %s)' % (repr(self.start), repr(self.length))
+
+	def __str__(self):
+		start, end = map(str, self.range())
+		return '%s - %s' % (start, end)
+
+	def __eq__(self, other):
+		return self.start == other.start and self.length == other.length
+
+	def __ne__(self, other):
+		return not self == other
+
+def week(year, week):
+	# Ensure that week is correct for the given year
+	assert(1 <= week and week <= 53)
+	if week == 53:
+		assert(datetime.date(year, 12, 31).isocalendar()[1] == 53)
+
+	# First attempt, this will most likely be wrong
+	# Use 28 instead of probably better 30 so we don't have to special-case february
+	days_into_year = 1 + week * 7
+	guess = datetime.date(year + days_into_year // 365, days_into_year // 28 % 12 + 1, week * 7 % 28 + 1)
+	guess_year, guess_week, guess_weekday = guess.isocalendar()
+
+	while guess_year != year or guess_week != week or guess_weekday != 1:
+		year_delta = year - guess_year
+		week_delta = week - guess_week
+		weekday_delta = 1 - guess_weekday
+
+		# Year is not quite right, but by repeated application year_delta should become 0, after which it's correct
+		delta = datetime.timedelta(year_delta * 365 + week_delta * 7 + weekday_delta)
+
+		guess += delta
+		guess_year, guess_week, guess_weekday = guess.isocalendar()
+
+	return Daterange(guess, datetime.timedelta(7))
+
+def between(start, end):
+	assert(len(start) == 3 and len(end) == 3)
+	start_year, start_month, start_day = start
+	end_year, end_month, end_day = end
+	start_obj = datetime.date(start_year, start_month, start_day)
+	end_obj = datetime.date(end_year, end_month, end_day)
+	return Daterange(start_obj, end_obj - start_obj + datetime.timedelta(1))
diff --git a/lukkari/generate_timetable.py b/lukkari/generate_timetable.py
new file mode 100644
index 0000000..b9bcc04
--- /dev/null
+++ b/lukkari/generate_timetable.py
@@ -0,0 +1,18 @@
+import datetime
+from . import check_date
+
+def generate_timetable(day_range, courses):
+	start_date, end_date = day_range.range()
+	date = start_date
+	appointments = []
+	while True:
+		for name, info, date_filter in courses:
+			if check_date.check_day_match(date, date_filter):
+				appointments.append((date, name, info))
+
+		if date == end_date:
+			break
+
+		date += datetime.timedelta(1)
+
+	return appointments
diff --git a/lukkari/parse_coursefile.py b/lukkari/parse_coursefile.py
new file mode 100644
index 0000000..baf12ea
--- /dev/null
+++ b/lukkari/parse_coursefile.py
@@ -0,0 +1,131 @@
+def strip_comments(text):
+	lines = []
+	for line in text.split('\n'):
+		comment_start = line.find('#')
+		if comment_start != -1:
+			lines.append(line[:comment_start])
+		else:
+			lines.append(line)
+	return '\n'.join(lines)
+
+def parse_filter(text):
+	weekdays = {'mon': 1, 'tue': 2, 'wed': 3, 'thu': 4, 'fri': 5, 'sat': 6, 'sun': 7}
+	functions = ['date', 'week', 'weekday', 'and', 'or', 'not', 'if']
+	def eof():
+		nonlocal index, length
+		return index >= length
+
+	def skip_whitespace():
+		nonlocal index, length
+		while not eof() and text[index].isspace():
+			index += 1
+
+	def match(matches):
+		nonlocal index, length
+		assert(not eof())
+		assert(text[index] in matches)
+		index += 1
+
+	def read_atom():
+		nonlocal index, length
+		start = index
+
+		while not eof() and not text[index].isspace() and text[index] != ')':
+			index += 1
+
+		return text[start:index]
+
+	def subexpression():
+		nonlocal index, length
+		if not eof() and text[index] == '(':
+			match('(')
+			skip_whitespace()
+
+			elements = []
+
+			function = read_atom()
+			skip_whitespace()
+			assert(not eof())
+
+			assert(function in functions)
+			elements.append(function)
+
+			while not eof() and text[index] != ')':
+				elements.append(subexpression())
+				skip_whitespace()
+
+			match(')')
+
+			return elements
+
+		else:
+			atom = read_atom()
+			assert(len(atom) >= 1)
+
+			if atom in weekdays:
+				return weekdays[atom]
+			else:
+				split = atom.split('-')
+				assert(all(map(lambda x: x.isnumeric(), split)))
+				assert(len(split) == 2 or len(split) == 3)
+				return tuple(map(int, split))
+
+	index = 0
+	length = len(text)
+
+	skip_whitespace()
+	expression = subexpression()
+	skip_whitespace()
+	assert(eof())
+
+	return expression
+
+def parse(text):
+	def eof():
+		nonlocal index, length
+		return index >= length
+
+	def skip_whitespace():
+		nonlocal index, length
+		while not eof() and text[index].isspace():
+			index += 1
+
+	def match(matches):
+		nonlocal index, length
+		assert(not eof())
+		assert(text[index] in matches)
+		index += 1
+
+	def read_field():
+		nonlocal index, length
+		skip_whitespace()
+
+		start = index
+		while not eof() and text[index] not in [';', '\n']:
+			if text[index] == '\\':
+				index += 1
+			index += 1
+
+		return text[start:index].strip()
+
+	text = strip_comments(text)
+	index = 0
+	length = len(text)
+
+	courses = []
+	while not eof():
+		name = read_field()
+		match(';')
+
+		info = read_field()
+		match(';')
+
+		date_filter = parse_filter(read_field())
+		if not eof():
+			match('\n')
+
+		courses.append((name, info, date_filter))
+
+	assert(eof())
+
+	return courses