Properly document the damn thing.

README.md

@@ -2,15 +2,15 @@
 
 ib-clearance is a program which helps schools manage the entrance and exiting of their IB Diploma Program students. Due to the unique nature of IB students' timetables, the program helps to automatically check individual timetables and give clearance to students who have finished for the day.
 
-## Building
+## Building & running
 
-The code is currently designed to run on Python 3.6.*.
+The code is currently designed to run on Python 3.6.* and requires the [`getch`](https://pypi.org/project/getch/) module on platforms other than Windows.
 
-Binaries can be built using the `pyinstaller` package (`pyinstaller --onefile ib-clearance.py`).
+Binaries can be built using [`pyinstaller`](https://pypi.org/project/PyInstaller/): `pyinstaller --onefile ib-clearance.py`
 
 ## Database specification
 
-The program requires a SQLite database `database.db` in the working directory, containing data for all classes.
+The program requires a SQLite database `database.db` in the working directory, containing data for all school classes.
 
 `database.db` must contain:
 

TODO.md

@@ -6,6 +6,7 @@ To-Do List
 - [x] Make database contain data for all classes
 - [x] Flexible mandatory subjects
 - [x] Make script functional (sorta)
+- [x] Document the damn thing
 
 ## v0.3
 - [ ] Usability and GUI

ib-clearance.py

@@ -14,12 +14,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-
 import sqlite3
 import time
 from os import name
 
-# Import getch from msvcrt if running on Windows.
+# Windows has standard library getch, use that.
 if name == "nt":
     from msvcrt import getch
 else:
@@ -27,18 +26,23 @@ else:
 
 
 def connect_database(file):
-    """
-    Creates and returns Connection object.
-    :param file: database file
+    """Get database connection object.
+
+    Connect to SQLite database and return a connection object.
+
+    :param file: SQLite database
     """
     conn = sqlite3.connect(file)
     return conn
 
 
 def get_data(conn):
-    """
-    Requests student ID and returns integer tuple (id, class) with valid
-    student id, corresponding class no. (1 or 2) and extra subject IDs.
+    """Get student data.
+
+    Request student ID.  Return integer tuple (id, class, other) with
+    valid student ID, corresponding class number and "other" subject
+    IDs.
+
     :param conn: Connection object
     """
     try:
@@ -46,12 +50,10 @@ def get_data(conn):
 
         cur = conn.cursor()
         cur.execute("SELECT id, student_class, other FROM students")
-        ids = cur.fetchall()
+        ids = cur.fetchall()  # ids is list of tuples.
 
         for tup in ids:
-            # ids is list of tuples
             if id == tup[0]:
-                # return tuple x with valid id, class and extra class IDs
                 lis = list(tup)
                 lis[2] = lis[2].split()
                 return lis
@@ -63,13 +65,17 @@ def get_data(conn):
 
 
 def select_final_time(conn, day, stuple):
-    """
-    Returns ending time of final lesson student must attend, or None.
+    """Select student finishing time.
+
+    Returns ending time (type struct_time) of final lesson student must
+    attend on given day, or None if no lessons.
+
     :param conn: Connection object
     :param day: current weekday, lowercase str
-    :param stuple: tuple with student ID no. and class no., int
+    :param stuple: student data tuple returned by get_data
     """
     cur = conn.cursor()
+    # Select finishing time of IB lessons.
     cur.execute("""
         SELECT end_time
         FROM timetable
@@ -84,13 +90,14 @@ def select_final_time(conn, day, stuple):
             AND lesson_class = ?
         ORDER BY end_time DESC
         LIMIT 1
-        """, (stuple[0], day, stuple[1]))
+        """, (stuple[0], day, stuple[1]))  # Queries return None if no matches.
     ib_finish = cur.fetchone()
     if ib_finish is not None:
         ib_finish = parse_time_string(ib_finish[0])
 
+    # Select finishing time of other lessons.
     others = []
-    for sub in stuple[2]:
+    for subject in stuple[2]:
         cur.execute("""
             SELECT end_time
             FROM timetable
@@ -100,10 +107,10 @@ def select_final_time(conn, day, stuple):
                 AND lesson_class = ?
             ORDER BY end_time DESC
             LIMIT 1
-            """, (sub, stuple[0], day, stuple[1]))
-        other_finish = cur.fetchone()
-        if other_finish is not None:
-            others.append(parse_time_string(other_finish[0]))
+            """, (subject, stuple[0], day, stuple[1]))
+        subject_finish = cur.fetchone()
+        if subject_finish is not None:
+            others.append(parse_time_string(subject_finish[0]))
     if not others:
         others_finish = None
     else:
@@ -125,8 +132,11 @@ def select_final_time(conn, day, stuple):
 
 
 def parse_time_string(timestring):
-    """
-    Parses given 24h time string of format "HH:MM" into struct_time.
+    """Convert time string to tuple.
+
+    Parses given 24h time string of format "HH:MM" into the struct_time
+    object provided by library time.
+
     :param timestring: time string "HH:MM"
     """
     structtime = time.strptime(timestring, "%H:%M")
@@ -141,7 +151,7 @@ def main():
 
     while True:
         student_data = get_data(conn)
-        day = time.strftime("%A").lower()
+        day = time.strftime("%A").lower()  # db days are also lowercase.
         finish_time = select_final_time(conn, day, student_data)
         current_time = parse_time_string(time.strftime("%H:%M"))
 
@@ -154,13 +164,12 @@ def main():
 
         print("\nPress X key to exit, other key to run again.")
         key = getch()
-        # msvcrt.getch returns type bytes, decode into str.
         if isinstance(key, bytes):
+            # msvcrt.getch returns type bytes, decode into str.
             key = key.decode()
         if key.upper() == "X":
             break
 
 
-# Run main() if script is run standalone.
 if __name__ == "__main__":
     main()