from MP_records import records
import random as rd
import time
import csv
import codecs
import sys

sys.setrecursionlimit(15000)


# ---------- Binary Search Tree ----------
# Узел:
# {
#     "name": name,
#     "phone": phone,
#     "left": None,
#     "right": None
# }


def bst_insert(root, name, phone):
    """
    Вставляет новую запись или обновляет телефон по имени.
    Возвращает корень дерева.
    """
    if root is None:
        return {
            "name": name,
            "phone": phone,
            "left": None,
            "right": None
        }

    if name == root["name"]:
        root["phone"] = phone

    elif name < root["name"]:
        root["left"] = bst_insert(root["left"], name, phone)

    else:
        root["right"] = bst_insert(root["right"], name, phone)

    return root


def bst_find(root, name):
    """
    Поиск телефона по имени.
    """
    if root is None:
        return None

    if name == root["name"]:
        return root["phone"]

    if name < root["name"]:
        return bst_find(root["left"], name)

    return bst_find(root["right"], name)


def bst_find_min(node):
    """
    Возвращает узел с минимальным именем.
    """
    current = node

    while current["left"] is not None:
        current = current["left"]

    return current


def bst_delete(root, name):
    """
    Удаляет запись по имени.
    Возвращает новый корень дерева.
    """
    if root is None:
        return None

    if name < root["name"]:
        root["left"] = bst_delete(root["left"], name)

    elif name > root["name"]:
        root["right"] = bst_delete(root["right"], name)

    else:
        # Узел без левого потомка
        if root["left"] is None:
            return root["right"]

        # Узел без правого потомка
        if root["right"] is None:
            return root["left"]

        # Узел с двумя потомками
        successor = bst_find_min(root["right"])

        root["name"] = successor["name"]
        root["phone"] = successor["phone"]

        root["right"] = bst_delete(root["right"], successor["name"])

    return root


def bst_inorder(root, result):
    """
    Центрированный обход дерева.
    """
    if root is None:
        return

    bst_inorder(root["left"], result)

    result.append((root["name"], root["phone"]))

    bst_inorder(root["right"], result)


def bst_list_all(root):
    """
    Возвращает список записей в отсортированном порядке.
    """
    result = []
    bst_inorder(root, result)
    return result


# ---------- Benchmark helpers ----------

def build_bst(records_list):
    root = None

    for name, phone in records_list:
        root = bst_insert(root, name, phone)

    return root


def measure_bst(records_list, mode_name, repeats=5):
    rows = []

    insertion_times = []
    finding_times = []
    deletion_times = []

    for run_number in range(1, repeats + 1):
        data = records_list[:]

        if mode_name == "случайный":
            rd.shuffle(data)

        # А. Вставка
        root = None

        start = time.perf_counter()

        for name, phone in data:
            root = bst_insert(root, name, phone)

        end = time.perf_counter()

        insertion_time = end - start
        insertion_times.append(insertion_time)

        # Б. Поиск
        existing_names = [name for name, phone in rd.sample(data, 100)]
        missing_names = [f"None_{i}" for i in range(10)]

        search_names = existing_names + missing_names
        rd.shuffle(search_names)

        start = time.perf_counter()

        for name in search_names:
            bst_find(root, name)

        end = time.perf_counter()

        finding_time = end - start
        finding_times.append(finding_time)

        # В. Удаление
        delete_names = rd.sample(existing_names, 50)

        start = time.perf_counter()

        for name in delete_names:
            root = bst_delete(root, name)

        end = time.perf_counter()

        deletion_time = end - start
        deletion_times.append(deletion_time)

        rows.append(["BinarySearchTree", mode_name, "вставка", run_number, insertion_time])
        rows.append(["BinarySearchTree", mode_name, "поиск", run_number, finding_time])
        rows.append(["BinarySearchTree", mode_name, "удаление", run_number, deletion_time])

    rows.append(["BinarySearchTree", mode_name, "вставка", "среднее", sum(insertion_times) / repeats])
    rows.append(["BinarySearchTree", mode_name, "поиск", "среднее", sum(finding_times) / repeats])
    rows.append(["BinarySearchTree", mode_name, "удаление", "среднее", sum(deletion_times) / repeats])

    return rows


def save_results(rows, filename="results.csv"):
    with codecs.open(filename, "a+", "utf-16") as file:
        writer = csv.writer(file)
        writer.writerows(rows)


def run_shuffled(records_shuffled):
    rows = measure_bst(records_shuffled, "случайный")
    save_results(rows)
    return rows


def run_sorted(records_sorted):
    rows = measure_bst(records_sorted, "отсортированный")
    save_results(rows)
    return rows


# ---------- Manual tests ----------

def test():
    root = None

    root = bst_insert(root, "Ivan", "111")
    root = bst_insert(root, "Anna", "222")
    root = bst_insert(root, "Petr", "333")
    root = bst_insert(root, "Maria", "444")

    print(bst_find(root, "Anna"))       # 222
    print(bst_find(root, "Unknown"))    # None

    root = bst_insert(root, "Anna", "999")
    print(bst_find(root, "Anna"))       # 999

    root = bst_delete(root, "Ivan")

    print(bst_list_all(root))


if __name__ == "__main__":
    records_shuffled, records_sorted = records()

    run_shuffled(records_shuffled)
    run_sorted(records_sorted)