#!/usr/bin/env nix-shell
#! nix-shell -i python3 --pure
#! nix-shell -p python3

import os
import json
import subprocess
import re
from datetime import datetime
import time

tmp_path = '/tmp/waybar-scripts/updates'
json_cache = tmp_path + "/data.json"
git_repo = 'git@github.com:mjallen18/nix-config.git'

def cache_json(data):
    with open(json_cache, mode="w") as cache:
        json.dump(data, cache)

def create_folders():
    if not os.path.exists(tmp_path):
        os.makedirs(tmp_path)
    os.chdir(tmp_path)

def clone_repo():
    reset_repo()
    if os.path.exists(tmp_path) and len(os.listdir(tmp_path)) == 0:
        subprocess.run(["git", "clone", git_repo, tmp_path])

def check_for_flake_updates():
    return subprocess.run(["sudo", "nix", "flake", "update", "-I", tmp_path, tmp_path], capture_output=True, text=True)

def reset_repo():
    if os.path.exists(tmp_path) and not len(os.listdir(tmp_path)) == 0:
        subprocess.run(["git", "reset", "--hard"])
        subprocess.run(["git", "pull"])

def parse_output(output):
    updates_dict = {}
    updates = re.findall(r"(• Updated input '(.+)':((\n|\r|\n)(.+\((\d\d\d\d-\d\d-\d\d\)))){2})", output)
    for update in updates:
        input = re.findall(r"'(.+)':", update[0])[0].strip()
        dates = re.findall(r"(\d{4}-\d{2}-\d{2})", update[0])
        updates_dict[input] = dates
    return updates_dict

def check():
    data = {}
    # print("create folders")
    create_folders()
    # print("clone repo")
    clone_repo()
    # print("checking for updates")
    updates = check_for_flake_updates()
    updates_dict = parse_output(updates.stderr)

    if len(updates_dict.keys()) > 0:
        data["text"] = ("󰏕")
    else:
        data["text"] = (u"\u00A0")
    if len(updates_dict.keys()) <= 0:
        data["tooltip"] = ("flake inputs up to date")
    else:
        data["tooltip"] = ("flake input updates:\n\n")

        for input in updates_dict.keys():
            data["tooltip"] += "<b>{}</b>\n".format(input)
            data["tooltip"] += "Old Ref: {0} → {1}\n\n".format(updates_dict[input][0].strip(), updates_dict[input][1].strip())

    cache_json(data)

    print(json.dumps(data))

def read_cache():
    with open(json_cache, mode="r") as cache:
        print(json.dumps(json.load(cache)))

def main():
    now = int(datetime.now().strftime("%H"))
    if os.path.exists(json_cache):
        mtime = int(time.localtime(os.stat(json_cache).st_ctime).tm_hour)
    else:
        mtime = now + 1

    if (now % 2 == 0 and mtime < now) or not os.path.exists(json_cache):
        check()
    else:
        read_cache()

main()