import json
from datetime import datetime

# PDF courses: (SP, Name, Dozent, SWS, CP, Turnus, shortname in WebUntis)
# Only courses with SoSe or WiSe/SoSe turnus are relevant
PDF_COURSES = [
    # Aufbau
    ("Aufbau", "Praktikum Messtechnik", "Großmann", 2, 2, "SoSe", "E-MT.PR"),
    # Automat./Robotik
    ("Autom./Robotik", "Antriebstechnik", "Meyer", 4, 5, "SoSe", "E-ANT"),
    ("Autom./Robotik", "Automatisierungstechnik 1", "Zeller / Danzer", 4, 5, "WiSe/SoSe", "E-AUT.1"),
    ("Autom./Robotik", "Praktikum Automatisierungstechnik", "Zeller / Danzer", 2, 2, "WiSe/SoSe", "E-AUT.PR"),
    ("Autom./Robotik", "Robot Systems Engineering", "Dietrich", 4, 5, "SoSe", "E-RSE"),
    # Elektronik
    ("Elektronik", "Automobilelektronik", "Schurk", 2, 2, "WiSe/SoSe", "E-%AUTOM"),
    ("Elektronik", "Formula Student Electric", "Markgraf", 4, 5, "WiSe/SoSe", None),
    ("Elektronik", "Fortgeschrittene Messtechnik", "Großmann", 4, 5, "SoSe", "E-FMT"),
    ("Elektronik", "Schaltungstechnik", "Zedler", 4, 5, "WiSe/SoSe", "E-SCHT"),
    ("Elektronik", "Elektrische Maschinen", "Meyer", 4, 5, "SoSe", "E-ELMA"),
    # Energietechnik
    ("Energietechnik", "Erneuerbare Energien", "Schwägerl", 4, 5, "SoSe", "E-EREN"),
    ("Energietechnik", "Praktikum Erneuerbare Energien", "Schwägerl", 2, 2, "WiSe/SoSe", "E-EREN.PR"),
    ("Energietechnik", "Hochspannungstechnik", "Finkel", 4, 5, "SoSe", "E-HST"),
    ("Energietechnik", "Leistungselektronik", "Ritter", 4, 5, "SoSe", "E-LE"),
    # Information
    ("Information", "Eingebettete Echtzeitsysteme mit Praktikum", "Werthschulte", 4, 5, "SoSe", "E-EES"),
    ("Information", "Künstliche Intelligenz: Grundlagen und Anwendungen", "Legat", 4, 5, "SoSe", None),
    ("Information", "Digitale Zwillinge: Grundkonzepte und Anwendungen", "Legat", 4, 5, "SoSe", "E-DIGTWIN"),
    ("Information", "Industrial Security Basics", "Hollmann", 4, 5, "SoSe", "E-IS1C5"),
    ("Information", "Matlab/Simulink", "Werthschulte", 2, 2, "WiSe/SoSe", "E-MATLAB"),
    # Kommunikation
    ("Kommunikation", "Digitale Kommunikation mit Praktikum", "Kamuf", 4, 5, "SoSe", "E-DIGK"),
    ("Kommunikation", "Hochfrequenz-Schaltungstechnik mit Praktikum", "Stolle", 4, 5, "SoSe", "E-HFSCH"),
    ("Kommunikation", "Hochfrequenzsysteme mit Praktikum", "Stolle", 4, 5, "SoSe", "E-HFSYS"),
    ("Kommunikation", "Funktechnik in der Praxis", "Bögl", 2, 2, "SoSe", None),
    # Übergreifend
    ("Übergreifend", "Fertigungstechnik", "Dietrich", 4, 5, "SoSe", "E-FT"),
    ("Übergreifend", "Systems Engineering", "Frommelt", 4, 5, "WiSe/SoSe", None),
    ("Übergreifend", "Elektrokonstruktion mit E-Plan", "Danzer / Voicau-Ottlik", 2, 2, "SoSe", "E-%EPLAN"),
    ("Übergreifend", "Elektronikproduktion", "Dietrich / Baur", 2, 2, "SoSe", "E-EP"),
    ("Übergreifend", "Systemdenken im Produktentstehungsprozess", "Königbauer", 4, 5, "SoSe", "E-THINK"),
    ("Übergreifend", "Advanced Topics in Electrical Engineering", "Gastdozierende", 2, 2, "WiSe/SoSe", None),
    ("Übergreifend", "Amateurfunk", "Stolle", 2, 2, "WiSe/SoSe", None),
]

DAY_NAMES = {
    0: "Montag",
    1: "Dienstag",
    2: "Mittwoch",
    3: "Donnerstag",
    4: "Freitag",
    5: "Samstag",
}

with open("timetables.json", 'r') as f:
    timetables = json.load(f)

# Build lookup by shortname
by_shortname = {}
for course in timetables:
    by_shortname[course["shortname"]] = course

def get_slots(course_data):
    """Extract (day_name, start_time, end_time, room) tuples from timetable data."""
    slots = []
    for day in course_data["timetable"].get("days", []):
        for grid in day.get("gridEntries", []):
            start = datetime.fromisoformat(grid["duration"]["start"])
            end = datetime.fromisoformat(grid["duration"]["end"])
            day_name = DAY_NAMES[start.weekday()]
            start_time = start.strftime("%H:%M")
            end_time = end.strftime("%H:%M")

            rooms = []
            for room in (grid.get("position2") or []):
                if room.get("current"):
                    rooms.append(room["current"]["displayName"])
            room_str = "/".join(rooms) if rooms else ""

            slots.append((day_name, start_time, end_time, room_str))
    return slots

def merge_slots(slots):
    """Merge consecutive slots on the same day into single blocks."""
    if not slots:
        return []
    # Group by day
    by_day = {}
    for day, start, end, room in slots:
        by_day.setdefault(day, []).append((start, end, room))

    merged = []
    for day in DAY_NAMES.values():
        if day not in by_day:
            continue
        entries = sorted(by_day[day])
        # Merge consecutive entries (end of one == start of next, same day)
        current_start, current_end, current_room = entries[0]
        rooms = {current_room} if current_room else set()
        for start, end, room in entries[1:]:
            if start <= current_end:
                current_end = max(current_end, end)
                if room:
                    rooms.add(room)
            else:
                merged.append((day, current_start, current_end, "/".join(sorted(rooms))))
                current_start, current_end = start, end
                rooms = {room} if room else set()
        merged.append((day, current_start, current_end, "/".join(sorted(rooms))))
    return merged

kurse = []
no_data = []

for sp, name, dozent, sws, cp, turnus, shortname in PDF_COURSES:
    semester = "WS/SS" if "WiSe/SoSe" in turnus else "SS"

    course_data = by_shortname.get(shortname) if shortname else None

    if course_data:
        slots = get_slots(course_data)
        merged = merge_slots(slots)
    else:
        merged = []

    if not merged:
        no_data.append(name)

    entry = {
        "Vertiefung": sp,
        "Name": name,
        "Dozent": dozent,
        "Semester": semester,
        "SWS": str(sws),
        "CP": str(cp),
        "Tag1": "",
        "Startzeit1": "",
        "Ende1": "",
        "Raum1": "",
        "Tag2": "",
        "Startzeit2": "",
        "Ende2": "",
        "Raum2": "",
        "Tag3": "",
        "Startzeit3": "",
        "Ende3": "",
        "Raum3": "",
        "Tag4": "",
        "Startzeit4": "",
        "Ende4": "",
        "Raum4": "",
    }

    for i, slot in enumerate(merged[:4], 1):
        entry[f"Tag{i}"] = slot[0]
        entry[f"Startzeit{i}"] = slot[1]
        entry[f"Ende{i}"] = slot[2]
        entry[f"Raum{i}"] = slot[3]
    if len(merged) > 4:
        print(f"  WARNING: {name} has {len(merged)} time blocks, only first 4 used")

    kurse.append(entry)

with open("kurse.json", 'w') as f:
    json.dump(kurse, f, ensure_ascii=False, indent=2)

print(f"Generated kurse.json with {len(kurse)} courses")
if no_data:
    print(f"\nNo timetable data for {len(no_data)} courses:")
    for n in no_data:
        print(f"  - {n}")