#!/usr/bin/env python3
import os
import sys
import json
import shutil
import subprocess

BASE_DIR = os.path.expanduser("~/.dotsync")
SYNC_DIR = os.path.join(BASE_DIR, "sync")
CONFIG_FILE = os.path.join(BASE_DIR, "config.json")

def run(cmd, cwd=None):
    return subprocess.run(cmd, cwd=cwd, text=True, capture_output=True)

def load_config():
    if not os.path.exists(CONFIG_FILE):
        return {"files": []}
    with open(CONFIG_FILE, "r") as f:
        return json.load(f)

def save_config(cfg):
    with open(CONFIG_FILE, "w") as f:
        json.dump(cfg, f, indent=4)

def ensure_dirs():
    os.makedirs(SYNC_DIR, exist_ok=True)

def init_repo(repo_link):
    ensure_dirs()
    if os.listdir(SYNC_DIR):
        print(f"{SYNC_DIR} ist nicht leer. Bitte leere das Verzeichnis oder verschiebe alte Dateien.")
        sys.exit(1)

    print(f"Klone Repository von {repo_link} in {SYNC_DIR} ...")
    res = run(["git", "clone", repo_link, SYNC_DIR])
    if res.returncode != 0:
        print("Fehler beim Klonen:", res.stderr)
        sys.exit(1)

    if not os.path.exists(CONFIG_FILE):
        save_config({"files": []})

    print("Repository erfolgreich eingerichtet!")
    print("Verwende jetzt: dotsync add, push, pull, list, remove")

def add_file(filename):
    expanded = os.path.expanduser(filename)
    path = os.path.abspath(expanded)

    # Pfad in Config als ~/... speichern, falls im Home
    home = os.path.expanduser("~")
    if path.startswith(home):
        path_in_config = "~" + path[len(home):]
    else:
        path_in_config = path

    cfg = load_config()
    if path_in_config not in cfg["files"]:
        cfg["files"].append(path_in_config)
        save_config(cfg)
        print(f"Datei {path_in_config} zur Sync-Liste hinzugefügt.")
    else:
        print(f"Datei {path_in_config} ist bereits in der Liste.")

def remove_file(filename):
    expanded = os.path.expanduser(filename)
    path = os.path.abspath(expanded)

    home = os.path.expanduser("~")
    if path.startswith(home):
        path_in_config = "~" + path[len(home):]
    else:
        path_in_config = path

    cfg = load_config()
    if path_in_config in cfg["files"]:
        cfg["files"].remove(path_in_config)
        save_config(cfg)
        print(f"Datei {path_in_config} aus der Sync-Liste entfernt.")
    else:
        print(f"Datei {path_in_config} ist nicht in der Sync-Liste.")

def list_files():
    cfg = load_config()
    if not cfg["files"]:
        print("Keine Dateien in der Sync-Liste.")
    else:
        print("Dateien in der Sync-Liste:")
        for f in cfg["files"]:
            print(f" - {f}")

def copy_with_structure(src, base_dir):
    abs_src = os.path.abspath(os.path.expanduser(src))
    home = os.path.expanduser("~")
    if abs_src.startswith(home):
        rel_path = abs_src[len(home)+1:]  # Pfad relativ zu Home
    else:
        rel_path = os.path.basename(abs_src)  # außerhalb Home, nur Dateiname
    dest = os.path.join(base_dir, rel_path)
    os.makedirs(os.path.dirname(dest), exist_ok=True)
    shutil.copy2(abs_src, dest)
    return dest


def push_files():
    ensure_dirs()
    print("Kopiere Dateien ins Sync-Verzeichnis...")
    cfg = load_config()
    for f in cfg["files"]:
        home_path = os.path.expanduser(f)
        if not os.path.exists(home_path):
            print(f"{home_path} existiert nicht, übersprungen.")
            continue

        # Determine target path inside sync, relative to home
        rel_path = os.path.relpath(home_path, os.path.expanduser("~"))
        dest_path = os.path.join(SYNC_DIR, rel_path)
        os.makedirs(os.path.dirname(dest_path), exist_ok=True)
        shutil.copy2(home_path, dest_path)
        print(f"{home_path} → {dest_path}")

    print("Committing & Push...")
    run(["git", "add", "."], cwd=SYNC_DIR)
    run(["git", "commit", "-m", "dotsync push"], cwd=SYNC_DIR)
    run(["git", "push"], cwd=SYNC_DIR)
    print("Fertig!")


def pull_files():
    ensure_dirs()
    print("Lade Änderungen vom Remote...")
    run(["git", "pull", "--rebase"], cwd=SYNC_DIR)

    cfg = load_config()
    files_to_pull = cfg.get("files", [])

    # If empty → full copy except .git
    if not files_to_pull:
        print("Sync-Liste leer → kopiere alle Dateien aus dem Repo außer .git...")
        for root, dirs, files in os.walk(SYNC_DIR):
            if ".git" in dirs:
                dirs.remove(".git")
            for file in files:
                src = os.path.join(root, file)
                rel_path = os.path.relpath(src, SYNC_DIR)
                dest = os.path.expanduser(os.path.join("~", rel_path))
                os.makedirs(os.path.dirname(dest), exist_ok=True)
                shutil.copy2(src, dest)
                print(f"{src} → {dest}")
        return

    print("Kopiere Dateien ins Home-Verzeichnis laut Liste...")
    for f in files_to_pull:
        home_path = os.path.expanduser(f)
        rel_path = os.path.relpath(home_path, os.path.expanduser("~"))
        src_path = os.path.join(SYNC_DIR, rel_path)
        if os.path.exists(src_path):
            os.makedirs(os.path.dirname(home_path), exist_ok=True)
            shutil.copy2(src_path, home_path)
            print(f"{src_path} → {home_path}")
        else:
            print(f"{src_path} nicht im Repo, übersprungen.")


def main():
    if len(sys.argv) < 2:
        print("Usage: dotsync <init|add|remove|list|push|pull> [filename|repo-link]")
        sys.exit(1)

    cmd = sys.argv[1]

    if cmd == "init":
        if len(sys.argv) < 3:
            print("Bitte GitHub-Link angeben (z. B. dotsync init https://github.com/user/dotfiles.git)")
            sys.exit(1)
        init_repo(sys.argv[2])
    elif cmd == "add":
        if len(sys.argv) < 3:
            print("Bitte Datei angeben.")
            sys.exit(1)
        add_file(sys.argv[2])
    elif cmd == "remove":
        if len(sys.argv) < 3:
            print("Bitte Datei angeben, die entfernt werden soll.")
            sys.exit(1)
        remove_file(sys.argv[2])
    elif cmd == "list":
        list_files()
    elif cmd == "push":
        push_files()
    elif cmd == "pull":
        pull_files()
    else:
        print("Unbekannter Befehl. Nutze: init, add, remove, list, push, pull.")

if __name__ == "__main__":
    main()