import json
import csv
import codecs

def decode_unicode_escapes(data):
    if isinstance(data, str):
        return codecs.decode(data, 'unicode_escape')
    elif isinstance(data, dict):
        return {key: decode_unicode_escapes(value) for key, value in data.items()}
    elif isinstance(data, list):
        return [decode_unicode_escapes(element) for element in data]
    else:
        return data

# Load data from JSON file with UTF-8 encoding
with open('data.json', 'r', encoding='utf-8') as f:
    raw_data = f.read()

# Decode Unicode escape sequences
decoded_data = decode_unicode_escapes(raw_data)

# Parse the JSON data
data = json.loads(decoded_data)

teachers = data['teachers']
classes = data['classes']
subjects = data['subjects']
classrooms = data['classrooms']

teacherid = 1
teacherEduMap = {}
teacherClassroomMap = {}
teacher_dicts = []
for eduID, teacher in teachers.items():
    firstname = teacher["firstname"]
    lastname = teacher["lastname"]
    isFemale = 0 if teacher["gender"] == "M" else 1
    classroom = teacher["classroomid"] or 0
    if classroom:
        teacherClassroomMap[classroom] = teacherid
    short = teacher["short"]
    startedTeaching = teacher["datefrom"]
    teacher_dicts.append([teacherid, eduID, firstname, lastname, isFemale, classroom, short, startedTeaching])
    teacherEduMap[eduID] = teacherid
    teacherid += 1

subjectID = 1
subjectEduMap = {}
subject_dicts = []
for eduID, subject in subjects.items():
    name = subject["name"]
    short = subject["short"]
    subject_dicts.append([subjectID, eduID, name, short])
    subjectEduMap[eduID] = subjectID
    subjectID += 1

classroomID = 1
classroomEduMap = {}
classroom_dicts = []
for eduID, classroom in classrooms.items():
    name = classroom["name"]
    short = classroom["short"]
    teacher = teacherClassroomMap.get(eduID, 0)
    classroom_dicts.append([classroomID, eduID, name, short, teacher])
    classroomEduMap[eduID] = classroomID
    classroomID += 1

classID = 1
classEduMap = {}
class_dicts = []
for eduID, classobj in classes.items():
    name = classobj["name"]
    short = classobj["short"]
    grade = classobj["grade"]
    classTeacher = teacherEduMap.get(classobj["teacherid"], 0)
    backupTeacher = teacherEduMap.get(classobj["teacher2id"], 0)
    classroom = classroomEduMap.get(classobj["classroomid"], 0)
    class_dicts.append([classID, eduID, grade, name, short, classTeacher, backupTeacher, classroom])
    classEduMap[eduID] = classID
    classID += 1

for teacher in teacher_dicts:
    if teacher[5] not in classroomEduMap:
        classroomEduMap[teacher[5]] = 0
    teacher_dicts[teacher[0] - 1][5] = classroomEduMap[teacher[5]]

# Write dictionaries to CSV files
with open('teachers.csv', 'w', encoding="utf-8", newline='') as csvfile:
    writer = csv.writer(csvfile, delimiter=',', quotechar='"', quoting=csv.QUOTE_ALL)
    writer.writerows(teacher_dicts)

with open('subjects.csv', 'w', encoding="utf-8", newline='') as csvfile:
    writer = csv.writer(csvfile, delimiter=',', quotechar='"', quoting=csv.QUOTE_ALL)
    writer.writerows(subject_dicts)

with open('classrooms.csv', 'w', encoding="utf-8", newline='') as csvfile:
    writer = csv.writer(csvfile, delimiter=',', quotechar='"', quoting=csv.QUOTE_ALL)
    writer.writerows(classroom_dicts)

with open('classes.csv', 'w', encoding="utf-8", newline='') as csvfile:
    writer = csv.writer(csvfile, delimiter=',', quotechar='"', quoting=csv.QUOTE_ALL)
    writer.writerows(class_dicts)