lcar

#! /usr/bin/env python3

import os
import shutil
import subprocess

ALLOWED_TOPICS = [
    "Arrays & Hashing",
    "Backtracking",
    "Binary Search",
    "Binary Trees",
    "Bit Manipulation",
    "Dynamic Programming 1D",
    "Dynamic Programming 2D",
    "Graphs",
    "Graphs Advanced",
    "Greedy",
    "Heap Priority Queue",
    "Intervals",
    "Linked Lists",
    "Math & Geometry",
    "Prefix Sum",
    "Queue",
    "Sliding Window",
    "Stack",
    "Tries",
    "Two Pointers"
]

tracker_file = "README.md"

def read_parameters(filename: str) -> tuple[str, str, str, str]:
    """Extract topic and difficulty parameters from file."""
    title, number, difficulty, topic = None, None, None, None
    with open(filename, "r", encoding="utf-8") as file:
        lines = file.readlines()
        for line in lines:
            if line.lower().startswith("difficulty:"):
                difficulty = line.split(":", 1)[1].strip()
            if line.lower().startswith("topic:"):
                topic = line.split(":", 1)[1].strip()
            if line.lower().startswith("problem number:"):
                number = line.split(":", 1)[1].strip()
            if line.lower().startswith("leetcode problem:"):
                title = line.split(":", 1)[1].strip()
    return title, number, difficulty, topic

def get_topic_input() -> str:
    """Select topic from user input prompt."""
    while True:
        topic_index = int(input(f"\t{'\n\t'.join(f"{idx+1}. {name}" for idx, name in enumerate(ALLOWED_TOPICS))}\nChoose the topic: ")) - 1
        if topic_index >= 0 and topic_index < len(ALLOWED_TOPICS):
            return ALLOWED_TOPICS[topic_index]
        else:
            print("Invalid topic.")

def add_topic_to_file(filename: str, topic: str) -> None:
    """Save new topic to file in existing location."""
    with open(filename, "r+", encoding="utf-8") as file:
        lines = file.readlines()
        for i, line in enumerate(lines):
            if line.lower().startswith("topic:"):
                lines[i] = f"Topic: {topic}\n"
                break
        file.seek(0)
        file.writelines(lines)

def increase_value(s: str) -> str:
    """Increase value of one field in the markdown table."""
    return str(int(s.strip())+1)

def update_tracker(topic: str, difficulty: str) -> None:
    """Update markdown table tracker."""
    with open(tracker_file, "r+", encoding="utf-8") as file:
        lines = file.readlines()
        topic_line = f"| {topic} |"
        total_line = "| **Totals** |"

        for i, line in enumerate(lines):
            if line.startswith(topic_line) or line.startswith(total_line):
                fields = line[1:-2].split("|")
                
                if difficulty == 'Easy': fields[1] = increase_value(fields[1])
                elif difficulty == 'Medium': fields[2] = increase_value(fields[2])
                elif difficulty == 'Hard': fields[3] = increase_value(fields[3])
                fields[4] = increase_value(fields[4])
                
                lines[i] = f"| {' | '.join(field.strip() for field in fields)} |\n"
        
        file.seek(0)
        file.writelines(lines)

def is_inside_repo() -> None:
    """Checks if is running the command inside a repository."""
    result = subprocess.run(['git', 'rev-parse', '--is-inside-work-tree'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    return result.returncode == 0

def stage_changes(filepath: str, has_tracker: bool, number: str, title: str) -> None:
    """Commits the changes with a default message."""
    try:
        command = ['git', 'add', filepath]
        if has_tracker:
            command.append(tracker_file)

        subprocess.run(command, check=True)
        
        commit_message = f'Leetcode problem {number}: {title}'
        subprocess.run(['git', 'commit', '-m', commit_message], check=True)
        
    except subprocess.CalledProcessError as e:
        print(f"Git command failed: {e}")
    except Exception as e:
        print(f"An unexpected error occurred: {e}")

def archive_leetcode_file(filename: str) -> None:
    """Archive a leetcode file based on topic and difficulty."""
    if not os.path.isfile(filename):
        print(f"Error: file '{filename}' does not exist.")
        exit(1)

    title, number, difficulty, topic = read_parameters(filename)

    if not topic or not topic in ALLOWED_TOPICS:
        topic = get_topic_input()
        add_topic_to_file(filename, topic)

    folder = os.path.join(topic, difficulty)
    os.makedirs(folder, exist_ok=True)
    destination = os.path.join(folder, filename)
    shutil.move(filename, destination)

    print(f"> File '{filename}' archived in '{destination}'!")

    has_tracker_file = os.path.isfile(tracker_file) 
    if not has_tracker_file:
        return

    update_tracker(topic, difficulty)
    print(f"> '{topic}' and '{difficulty}' updated in '{tracker_file}'!")

    if not is_inside_repo():
        return

    stage_changes(destination, has_tracker_file, number, title)
    print(f"> Changes were stages successfully!")

if __name__ == "__main__":
    import sys
    if len(sys.argv) != 2:
        print("Usage: lcar <file_path>")
    else:
        filename = sys.argv[1]
        archive_leetcode_file(filename)