"""
Урок 59. Summary session 15 — весь код примеров одним файлом.

Источник: subjects/python-fundamentals/course/lessons/59-summary-session-15/examples.html
Файл собран автоматически (tools/build_lesson_examples.py): правьте страницу урока.
Запуск: python lesson-59.py
"""



# ====================================================================
# Пример 1. Генератор с yield
# ====================================================================
# generator_01_basic.py
def count_up_to(n: int):
    count = 1
    while count <= n:
        yield count
        count += 1


gen = count_up_to(5)
print(type(gen))
for number in gen:
    print(number)

# генератор одноразовый: второй проход ничего не даст
print(list(gen))
# <class 'generator'>
# 1
# 2
# 3
# 4
# 5
# []


# ====================================================================
# Пример 2. Бесконечный генератор и явная остановка
# ====================================================================
# generator_02_infinite.py
def infinite_counter(start: int = 1):
    count = start
    while True:
        yield count
        count += 1


gen = infinite_counter()
for number in gen:
    if number > 5:
        break
    print(number)
# 1
# 2
# 3
# 4
# 5


# ====================================================================
# Пример 3. yield from — делегирование другому генератору
# ====================================================================
# generator_03_yield_from.py
def process_values(data: list[int]):
    for value in data:
        yield value * 2


def main_generator(*sequences: list[int]):
    for seq in sequences:
        yield from process_values(seq)


for result in main_generator([1, 2, 3], [10, 15]):
    print(result)
# 2
# 4
# 6
# 20
# 30


# ====================================================================
# Пример 4. Принудительное закрытие генератора
# ====================================================================
# generator_04_close.py
def sensor_data(data: list[int]):
    for value in data:
        yield value


numbers = [10, 20, 30, 40, 50]
gen = sensor_data(numbers)
for element in gen:
    print("Получено значение:", element)
    if element >= 30:
        print("Значение найдено, закрываем генератор.")
        gen.close()
        break

try:
    next(gen)
except StopIteration as error:
    print("StopIteration после close():", repr(error))
# Получено значение: 10
# Получено значение: 20
# Получено значение: 30
# Значение найдено, закрываем генератор.
# StopIteration после close(): StopIteration()


# ====================================================================
# Пример 5. Почему генератор экономит память
# ====================================================================
# generator_05_memory.py
import sys

million = range(1_000_000)

as_list = [x * x for x in million]
as_generator = (x * x for x in million)

print("list:", sys.getsizeof(as_list), "байт")
print("generator:", sys.getsizeof(as_generator), "байт")

total_list = sum(as_list)
total_gen = sum(as_generator)
print("Суммы совпадают:", total_list == total_gen, total_list)
# list: 8448728 байт
# generator: 208 байт
# Суммы совпадают: True 333332833333500000


# ====================================================================
# Пример 6. Файлы: режимы, кодировка и with
# ====================================================================
# file_01_read_write.py
lines = ["Первая строка\n", "Вторая строка\n", "Третья строка\n"]

with open("demo.txt", "w", encoding="utf-8") as file:
    file.writelines(lines)

with open("demo.txt", "r", encoding="utf-8") as file:
    content = file.read()
print(repr(content))

with open("demo.txt", "r", encoding="utf-8") as file:
    for line in file:
        print(line.strip().upper())

with open("demo.txt", "a", encoding="utf-8") as file:
    file.write("Добавленная строка\n")

with open("demo.txt", "r", encoding="utf-8") as file:
    print(file.readlines())
# 'Первая строка\nВторая строка\nТретья строка\n'
# ПЕРВАЯ СТРОКА
# ВТОРАЯ СТРОКА
# ТРЕТЬЯ СТРОКА
# ['Первая строка\n', 'Вторая строка\n', 'Третья строка\n', 'Добавленная строка\n']


# ====================================================================
# Пример 7. Генератор для ленивого чтения файла
# ====================================================================
# file_02_lazy_reading_generator.py
def read_non_empty_lines(path: str):
    with open(path, "r", encoding="utf-8") as file:
        for line in file:
            stripped = line.strip()
            if stripped:
                yield stripped


with open("log.txt", "w", encoding="utf-8") as file:
    file.write("Строка 1\n\nСтрока 2\n   \nСтрока 3\n")

for entry in read_non_empty_lines("log.txt"):
    print(entry)
# Строка 1
# Строка 2
# Строка 3


# ====================================================================
# Пример 8. JSON: сериализация, десериализация и форматирование
# ====================================================================
# json_01_basic.py
import json

person = {"name": "Alice", "age": 25, "is_student": False, "pet": None}
json_string = json.dumps(person, ensure_ascii=False, indent=2)
print(json_string)

loaded = json.loads(json_string)
print(loaded["name"], type(loaded))

city = {"country": "Беларусь", "city": "Минск"}
print(json.dumps(city))
print(json.dumps(city, ensure_ascii=False))
print(json.dumps(city, ensure_ascii=False, sort_keys=True))
# {
#   "name": "Alice",
#   "age": 25,
#   "is_student": false,
#   "pet": null
# }
# Alice <class 'dict'>
# {"country": "\u0411\u0435\u043b\u0430\u0440\u0443\u0441\u044c", "city": "\u041c\u0438\u043d\u0441\u043a"}
# {"country": "Беларусь", "city": "Минск"}
# {"city": "Минск", "country": "Беларусь"}


# ====================================================================
# Пример 9. JSON: файл и обработка JSONDecodeError
# ====================================================================
# json_02_file_and_errors.py
import json

data = {"tasks": ["Купить билеты", "Сдать отчёт"], "count": 2}

with open("data.json", "w", encoding="utf-8") as file:
    json.dump(data, file, ensure_ascii=False, indent=2)

with open("data.json", "r", encoding="utf-8") as file:
    restored = json.load(file)
print(restored)

broken_json = "{'x': 1}"
try:
    json.loads(broken_json)
except json.JSONDecodeError as error:
    print("JSONDecodeError:", error)
# {'tasks': ['Купить билеты', 'Сдать отчёт'], 'count': 2}
# JSONDecodeError: Expecting property name enclosed in double quotes: line 1 column 2 (char 1)


# ====================================================================
# Пример 10. datetime: текущее время, форматы и разница дат
# ====================================================================
# datetime_01_basic.py
from datetime import datetime, timedelta

now = datetime.now()
print(type(now))
print(now.strftime("%d.%m.%Y %H:%M:%S"))

deadline = datetime.strptime("01.12.2026", "%d.%m.%Y")
days_left = (deadline - now).days
print(f"До дедлайна осталось дней: {days_left}")
print(deadline > now)

future = now + timedelta(weeks=2)
print(future.strftime("%Y-%m-%d"))
# <class 'datetime.datetime'>
# 13.08.2026 21:01:02   (у вас будет другое время — используется текущий момент)
# До дедлайна осталось дней: 109         (у вас будет другое число — зависит от сегодняшней даты)
# True
# 2026-08-27                             (у вас будет другая дата — это "через 2 недели от сегодня")


# ====================================================================
# Пример 11. Капстоун: просроченные задачи из JSON через генератор
# ====================================================================
# capstone_overdue_tasks.py
import json
from datetime import datetime

tasks_json = """
[
  {"title": "Audit finances", "deadline": "23-12-2025", "status": "done"},
  {"title": "Plan event", "deadline": "15-09-2025", "status": "pending"},
  {"title": "Team meeting", "deadline": "15-04-2025", "status": "pending"},
  {"title": "Backup server", "deadline": "19-03-2025", "status": "pending"},
  {"title": "Sign contract", "deadline": "28-07-2025", "status": "pending"}
]
"""


def load_tasks(raw_json: str):
    return json.loads(raw_json)


def overdue_tasks(tasks: list[dict], check_date: datetime):
    for task in tasks:
        if task["status"] != "pending":
            continue
        deadline = datetime.strptime(task["deadline"], "%d-%m-%Y")
        if deadline < check_date:
            yield task


tasks = load_tasks(tasks_json)
check_date = datetime.strptime("01-08-2025", "%d-%m-%Y")

for task in overdue_tasks(tasks, check_date):
    print(f"- {task['title']} ({task['deadline']})")
# - Team meeting (15-04-2025)
# - Backup server (19-03-2025)
# - Sign contract (28-07-2025)