commit first working version

Author: kguzek

.gitignore

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+__pycache__
+dist
+*.egg-info

LICENSE

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+# LeetCode Project Generator
+
+Copyright (c) 2023 Konrad Guzek
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

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+# LeetCode Project Generator
+
+A CLI tool created using [Click](https://click.palletsprojects.com/en/8.1.x/).
+This utility creates a barebones project template from the URL of a LeetCode problem.
+
+## Usage
+
+Ensure the package is recognised on PYTHONPATH, and invoke using the command:
+
+```sh
+python lpg.py (--title_slug <problem title> | --url <problem url>) [--directory <project directory>] [--lang <language>] [--force] [--git-init]
+```
+
+"Title slug" refers to the dashed title of the LeetCode problem which can be found in the URL of the problem.
+E.g. for [https://leetcode.com/problems/two-sum/](https://leetcode.com/problems/two-sum/), the title slug is `two-sum`.
+
+The default language is C. Other languages are currently unsupported.
+If using Bash, you must surround the URL with quotes, since the `&` symbol would be interpreted as an asynchronous command.
+
+The project directory defaults to `~/Documents/Coding/{language_name}/`. You may use use the template `{language_name}` when specifying the directory, and this will automatically be translated into the name of the language specified using `--lang`. E.g.: `cpp -> C++`.
+The project will be created in its own directory with the name of the title slug within this directory. This is unchangeable.
+
+For more syntax help, use the `help` option.
+
+```sh
+python lpg.py --help
+```
+
+Planned available languages:
+
+- python
+- python3
+- javascript
+- typescript
+- c
+- cpp
+- csharp
+- java
+- php
+- swift
+- kotlin
+- dart
+- golang
+- ruby
+- scala
+- rust
+- racket
+- erlang
+- elixir
+
+Thanks for reading!

pyproject.toml

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+[build-system]
+requires = ["setuptools>=61.0"]
+build-backend = "setuptools.build_meta"
+
+[project]
+name = "lpg"
+version = "1.0.0"
+authors = [{ name = "Konrad Guzek", email = "konrad@guzek.uk" }]
+description = "A LeetCode project template generator."
+readme = "README.md"
+requires-python = ">=3.10"
+classifiers = [
+  "Programming Language :: Python :: 3",
+  "License :: OSI Approved :: MIT License",
+  "Operating System :: OS Independent",
+]
+
+[project.urls]
+Homepage = "https://github.com/kguzek/leetcode-project-generator"
+Issues = "https://github.com/kguzek/leetcode-project-generator/issues"

requirements.txt

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+click

setup.py

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+import setuptools
+
+module_name = "lpg"
+setuptools.setup(
+    name=module_name,
+    py_modules=[module_name],
+)

src/lpg/__init__.py

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+"""Package definition for the LeetCode Project Generator."""

src/lpg/interfaces/__init__.py

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+"""Package definition for various APIs."""

src/lpg/interfaces/file.py

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+"""API for accessing various OS and filesystem functions."""
+
+
+import os
+from click import ClickException
+
+from .lang import c
+
+
+def create_project_directory(project_path: str, force: bool):
+    """Creates the project directory. If it already exists, throws a `ClickException`."""
+    try:
+        os.makedirs(project_path, exist_ok=force)
+    except FileExistsError as error:
+        raise ClickException(
+            f"Cannot create project with path '{project_path}' as it already exists."
+        ) from error
+    except OSError as error:
+        raise ClickException(f"Invalid project path '{project_path}'") from error
+    return project_path
+
+
+def create_project(
+    project_name: str, project_directory: str, template_data: dict, force: bool
+):
+    """Creates the entire project."""
+
+    language_code = template_data["langSlug"]
+    language_name = template_data["lang"]
+    template = template_data["code"]
+
+    project_path = os.path.expanduser(
+        os.path.join(
+            project_directory.format(language_name=language_name), project_name
+        )
+    )
+    create_project_directory(project_path, force)
+    os.chdir(project_path)
+
+    match language_code:
+        case "c":
+            c.create_c_project(template)
+        case "*":
+            raise ClickException(f"{language_name} projects are currently unsupported.")

src/lpg/interfaces/lang/c.py

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+"""Project generator for the C language."""
+
+
+import re
+
+HEADER_FILE_TEMPLATE = "{returnType} {name}({params});"
+
+TEST_FILE_TEMPLATE = """\
+#include <stdio.h>
+
+int main() {{
+    {param_declarations};
+    {returnType} result = {name}({params_call});
+    printf("result: %d\n", result);
+    return 0;
+}}
+"""
+
+FUNCTION_SIGNATURE_PATTERN = re.compile(
+    r"(?P<returnType>\w+(?:\[\]|\*)?) (?P<name>\w+)\((?P<params>(?:\w+(?:\[\]|\*)? \w+(?:, )?)+)\) {"
+)
+
+
+def create_c_project(template: str):
+    """Creates the project template for C."""
+
+    match = FUNCTION_SIGNATURE_PATTERN.search(template, re.MULTILINE)
+    if match is None:
+        raise RuntimeError("Fatal error: project template doesn't match regex.")
+    groups = match.groupdict()
+
+    with open("solution.c", "w", encoding="utf-8") as file:
+        file.write(template + "\n")
+
+    with open("solution.h", "w", encoding="utf-8") as file:
+        file.write(HEADER_FILE_TEMPLATE.format(**groups))
+
+    params = groups["params"].split(", ")
+    groups["param_declarations"] = groups["params"].replace(", ", ";\n    ")
+    groups["params_call"] = ", ".join(param.split()[1] for param in params)
+    formatted = TEST_FILE_TEMPLATE.format(**groups)
+
+    with open("test.c", "w", encoding="utf-8") as file:
+        file.write(formatted)

src/lpg/interfaces/web.py

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+"""The API for accessing LeetCode's front end."""
+
+import json
+import re
+import urllib.error
+import urllib.parse
+import urllib.request
+from http.client import HTTPResponse
+
+from click import ClickException
+
+URL_TITLE_SLUG_PATTERN = re.compile(
+    r"^https://leetcode\.com/problems/(?P<slug>[-\w]+)/"
+)
+TITLE_SLUG_PATTERN = re.compile(r"\w+(?:-\w+)+")
+
+LEETCODE_API_URL = "https://leetcode.com/graphql/"
+GRAPHQL_QUERY_TEMPLATE = """
+query questionEditorData($titleSlug: String!) {
+  question(titleSlug: $titleSlug) {
+    # questionId
+    # questionFrontendId
+    codeSnippets {
+      lang
+      langSlug
+      code
+    }
+    # envInfo
+    # enableRunCode
+  }
+}
+"""
+FAKE_USER_AGENT = "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.64 Safari/537.11"
+
+
+def _validate_title_slug(title_slug: str) -> str:
+    match = TITLE_SLUG_PATTERN.fullmatch(title_slug)
+    if match is None:
+        raise ClickException(f"Invalid title slug '{title_slug}'.")
+
+
+def _get_title_slug(problem_url: str) -> str:
+    match = URL_TITLE_SLUG_PATTERN.match(problem_url)
+    if match is None:
+        raise ClickException(f"Invalid LeetCode problem URL '{problem_url}'.")
+    title_slug = match.group("slug")
+    return title_slug
+
+
+def _create_graphql_request(title_slug: str):
+    """Creates a GraphQL query to fetch the problem code using the title slug."""
+    body = {"query": GRAPHQL_QUERY_TEMPLATE, "variables": {"titleSlug": title_slug}}
+    body_bytes = bytes(json.dumps(body), encoding="utf-8")
+    headers = {"User-Agent": FAKE_USER_AGENT, "Content-Type": "application/json"}
+    request = urllib.request.Request(
+        LEETCODE_API_URL, body_bytes, method="POST", headers=headers
+    )
+    return request
+
+
+def _get_body_from_request(request: urllib.request.Request) -> dict:
+    try:
+        response: HTTPResponse = urllib.request.urlopen(request)
+    except urllib.error.URLError as error:
+        print(str(error))
+        raise ClickException(f"Could not get data from API.") from error
+    text = response.read()
+    body: str = text.decode("utf-8")
+    data = json.loads(body)
+    return data
+
+
+def _get_template_data_from_body(body: dict, lang: str) -> dict[str, any]:
+    question = body["data"]["question"]
+    try:
+        code_snippets = question["codeSnippets"]
+    except TypeError:
+        raise ClickException("Invalid title slug.")
+    for lang_data in code_snippets:
+        if lang_data["langSlug"] != lang:
+            continue
+        return lang_data
+    else:
+        raise ClickException(f"Invalid code language '{lang}'.")
+
+
+def get_leetcode_template(title_slug: str, url: str, lang: str):
+    if url is None:
+        if title_slug is None:
+            raise ClickException("Either url or title slug must be specified.")
+    else:
+        title_slug = _get_title_slug(url)
+    request = _create_graphql_request(title_slug)
+    body = _get_body_from_request(request)
+    template_data = _get_template_data_from_body(body, lang)
+    with open("a.json", "w", encoding="utf-8") as file:
+        json.dump(template_data, file)
+    return title_slug, template_data

src/lpg/lpg.py

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+"""
+LeetCode Project Generator
+A program that automatically generates a C project template given the LeetCode problem URL.
+
+Author: Konrad Guzek
+"""
+
+import subprocess
+
+import click
+
+from interfaces import web as web_interface
+from interfaces import file as file_interface
+
+# TODO: Update
+SUPPORTED_LANGUAGES = ["c"]
+
+
+@click.command()
+@click.option(
+    "--title-slug",
+    "-s",
+    help="The dash-separated name of the problem as it appears in the URL.",
+)
+@click.option(
+    "--url",
+    "-u",
+    help="The URL to the LeetCode problem webpage.",
+)
+@click.option(
+    "--lang",
+    "-l",
+    help="The language of the code to generate.",
+    default="c",
+)
+@click.option(
+    "--directory",
+    "-d",
+    help="The directory for the project to be created in.",
+    default=R"~/Documents/Coding/{language_name}/leetcode/",
+)
+@click.option(
+    "--force",
+    "-f",
+    help="Force-creates the project directory even if it already exists.",
+    default=False,
+    is_flag=True,
+    show_default=True,
+)
+@click.option(
+    "--git-init",
+    "-g",
+    help="Initialises a git repository in the project directory.",
+    default=False,
+    is_flag=True,
+    show_default=False,
+)
+def lpg(
+    title_slug: str, url: str, lang: str, directory: str, force: bool, git_init: bool
+):
+    """CLI Entry point."""
+    if lang not in SUPPORTED_LANGUAGES:
+        raise click.ClickException(f"Unsupported language {lang}.")
+    title_slug, template_data = web_interface.get_leetcode_template(
+        title_slug, url, lang
+    )
+    title_slug = "least-sum"
+    file_interface.create_project(title_slug, directory, template_data, force)
+    if git_init:
+        subprocess.run("git init")
+
+
+if __name__ == "__main__":
+    lpg()