import json
import sys
import csv

def load(path):
    data = []
    with open(path, 'r', encoding='utf8') as fp:
        reading = csv.DictReader(fp)
        for row in reading:
            data.append(row['JSON'])
        return data

def save(saving_csv, name_csv):
    with open(name_csv + '.csv', 'w', encoding= 'utf8', newline='') as f:
        writer = csv.DictWriter(f, fieldnames=['JSON'])
        writer.writeheader()
        for radek in saving_csv:
            writer.writerow({'JSON': radek})

def delete(csv_json, clear_json):
    for s in csv_json:
        if isinstance(s, str) and ',' in s:
            idx = s.rfind(',')
            clear_json.add(s[:idx])
        else:
            clear_json.add(s)

def loadcsv(pattern_csv, target_csv):
    missing = set()
    overstay = set()
    pattern_jsons = set(json.dumps(json.loads(x), sort_keys=True) for x in pattern_csv)
    target_jsons = set(json.dumps(json.loads(x), sort_keys=True) for x in target_csv)
    missing_jsons = pattern_jsons - target_jsons
    overstay_jsons = target_jsons - pattern_jsons
    delete(missing_jsons, missing)
    delete(overstay_jsons, overstay)
    save(missing, 'pridat')
    save(overstay, 'odebrat')

def main():
    if len(sys.argv) < 3:
        print('Chybi cesta k csv souborum.', file=sys.stderr)
        print('Zadejte takto: <nazev_programu.py> <cesta k vzorove.csv> <cesta k cilove.csv>', file=sys.stderr)
        sys.exit(1)
    path_pattern = sys.argv[1] 
    path_target = sys.argv[2]
    pattern = load(path_pattern)
    target = load(path_target)

    loadcsv(pattern, target)

if __name__ == '__main__':
    main()
    sys.exit(0)