from dataclasses import dataclass
from typing import Iterable, Dict
import json
import time


File = str # typedef для имен файла ("явное лучше неявного" python-zen)
Username = str
Time = time.struct_time


@dataclass
class Employee:
    username: str
    commits: int
    changed_lines: int
    new_files: int


@dataclass
class FileChanges:
    name: File
    changed_lines: int


@dataclass
class Commit:
    username: Username
    commit_time: Time
    files: Iterable[FileChanges]


def parse_file(file: dict) -> FileChanges:
    return FileChanges(
        name=file["name"],
        changed_lines=int(file["changed_lines"])
    )


def parse_commit(data: dict) -> Commit:
    return Commit(
        username=data["username"],
        commit_time=time.strptime(data["commit_time"], "%Y/%m/%d %H:%M:%S"),
        files=tuple(parse_file(file) for file in data["files"])
    )


def get_commits_from_json(filename: str) -> Iterable[Commit]:
    with open(filename, "r") as json_file:
        data = json.load(json_file)

    return map(parse_commit, data)


def get_usernames(commits: Iterable[Commit]) -> Iterable[Username]:
    return set(commit.username for commit in commits)


def get_file_creators(commits: Iterable[Commit]) -> Dict[File, Username]:
    file_creators = dict()

    for commit in sorted(commits, key=lambda commit: commit.commit_time):
        for file in commit.files:
            if file.name not in file_creators:
                file_creators[file.name] = commit.username

    return file_creators


def get_changed_lines(commits: Iterable[Commit]) -> int:
    changed_lines = 0

    for commit in commits:
        changed_lines += sum(file.changed_lines for file in commit.files)

    return changed_lines


def get_employee(username: Username, commits: Iterable[Commit], file_creators: Dict[File, Username]) -> Employee:
    his_commits = tuple(commit for commit in commits if commit.username == username)

    return Employee(
        username=username,
        commits=len(his_commits),
        changed_lines=get_changed_lines(his_commits),
        new_files=sum(creator == username for creator in file_creators.values())
    )

commits = tuple(get_commits_from_json("./input.json"))
usernames = get_usernames(commits)
file_creators = get_file_creators(commits)
employeers = []

for username in usernames:
    employeers.append(get_employee(username, commits, file_creators))

print(employeers)

header = ["username", "commits", "changed_lines", "new_files"]

with open("output.tsv", "w") as file:
    file.write("{}\n".format("\t".join(header)))

    for employee in sorted(employeers, key=lambda el: el.username):
        file.write("{}\n".format("\t".join(map(str, [
            employee.username,
            employee.commits,
            employee.changed_lines,
            employee.new_files
        ]))))