dotfiles/local-bin/.local/bin/dev-launcher

#!/usr/bin/env python3
"""i3 Dev Launcher - Launch development environments from git repositories"""

import argparse
import hashlib
import json
import os
import re
import shutil
import subprocess
import sys
import time
from pathlib import Path

CACHE_MAX_AGE = 300
MRU_SIZE = 5


def debug(msg):
    if os.getenv("DEBUG") == "1":
        print(f"[DEBUG] {msg}", file=sys.stderr)


def get_cache_files(dev_dir):
    dev_dir_hash = hashlib.sha256(dev_dir.encode()).hexdigest()[:16]
    cache_dir = Path.home() / ".cache"
    return (
        cache_dir / f"i3-dev-launcher-cache-{dev_dir_hash}",
        cache_dir / f"i3-dev-launcher-mru-{dev_dir_hash}",
    )


_HAS_FD = None


def _has_fd():
    global _HAS_FD
    if _HAS_FD is None:
        _HAS_FD = shutil.which("fd") is not None
    return _HAS_FD


def find_git_repos(dev_dir, no_cache=False):
    cache_file, _ = get_cache_files(dev_dir)

    if not no_cache and cache_file.exists():
        if time.time() - os.path.getmtime(cache_file) < CACHE_MAX_AGE:
            return [r for r in cache_file.read_text().splitlines() if r]

    if not Path(dev_dir).exists():
        return []

    if _has_fd():
        result = subprocess.run(
            ["fd", "-H", "-t", "d", "^\\.git$", dev_dir, "-d", "4", "-0"],
            capture_output=True,
            text=True,
        )
    else:
        result = subprocess.run(
            ["find", dev_dir, "-maxdepth", "4", "-type", "d", "-name", ".git", "-print0"],
            capture_output=True,
            text=True,
        )

    repos = []
    if result.returncode == 0:
        repos = [str(Path(p).parent) for p in result.stdout.strip("\0").split("\0") if p]

    repos = sorted(set(repos))
    cache_file.parent.mkdir(parents=True, exist_ok=True)
    cache_file.write_text("\n".join(repos))
    return repos


def get_project_name(repo_path):
    name = Path(repo_path).name.lower()
    name = re.sub(r"[^a-z0-9]", "-", name)
    name = re.sub(r"-+", "-", name)
    return name.strip("-")


def update_mru(selected_display, dev_dir):
    _, mru_file = get_cache_files(dev_dir)
    mru = mru_file.read_text().splitlines() if mru_file.exists() else []
    mru = [x for x in mru if x != selected_display]
    mru.insert(0, selected_display)
    mru_file.parent.mkdir(parents=True, exist_ok=True)
    mru_file.write_text("\n".join(mru[:MRU_SIZE]))


def sort_by_mru(display_list, dev_dir):
    _, mru_file = get_cache_files(dev_dir)
    if not mru_file.exists():
        return sorted(display_list)

    mru = [x for x in mru_file.read_text().splitlines() if x]
    mru_set = set(mru)

    starred = [f"⭐ {d}" for d in display_list if d in mru_set]
    rest = [d for d in display_list if d not in mru_set]
    return sorted(starred) + sorted(rest)


def find_window_by_class(class_name):
    try:
        result = subprocess.run(
            ["i3-msg", "-t", "get_tree"],
            capture_output=True,
            text=True,
            check=False,
        )
        tree = json.loads(result.stdout)

        def walk(node):
            wp = node.get("window_properties") or {}
            if wp.get("class", "").lower() == class_name.lower():
                return node.get("id")
            for child in node.get("nodes", []) + node.get("floating_nodes", []):
                found = walk(child)
                if found:
                    return found
            return None

        return walk(tree)
    except Exception:
        return None


def focus_or_launch_alacritty(class_name, title, working_dir, session_name):
    window_id = find_window_by_class(class_name)

    if window_id:
        subprocess.run(
            ["i3-msg", f"[con_id={window_id}] focus"],
            stdout=subprocess.DEVNULL,
            stderr=subprocess.DEVNULL,
        )
        return

    editor = "nvim"
    tmux_cmd = f"""if tmux has-session -t '{session_name}' 2>/dev/null; then
    tmux attach -t '{session_name}';
else
    tmux new-session -c '{working_dir}' -s '{session_name}' -d '{editor}';
    tmux split-window -h -c '{working_dir}' -t '{session_name}';
    tmux select-pane -t '{session_name}:0.0';
    tmux attach -t '{session_name}';
fi"""

    subprocess.Popen(
        [
            "alacritty",
            "--class",
            f"{class_name},{class_name}",
            "--title",
            title,
            "--working-directory",
            working_dir,
            "-e",
            "bash",
            "-c",
            tmux_cmd,
        ],
        stdout=subprocess.DEVNULL,
        stderr=subprocess.DEVNULL,
        start_new_session=True,
    )


def run_menu(options):
    if shutil.which("rofi"):
        proc = subprocess.Popen(
            ["rofi", "-dmenu", "-i", "-p", "dev", "-dpi", "1"],
            stdin=subprocess.PIPE,
            stdout=subprocess.PIPE,
            text=True,
        )
    else:
        proc = subprocess.Popen(
            ["dmenu", "-i", "-l", "20", "-p", "dev"],
            stdin=subprocess.PIPE,
            stdout=subprocess.PIPE,
            text=True,
        )

    out, _ = proc.communicate("\n".join(options))
    return out.strip()


def main():
    parser = argparse.ArgumentParser(description="i3 Dev Launcher")
    parser.add_argument("dev_dir", nargs="?", default=os.path.expanduser("~/Dev"))
    parser.add_argument("--no-cache", action="store_true")
    parser.add_argument("--clear-cache", action="store_true")
    args = parser.parse_args()

    cache_file, mru_file = get_cache_files(args.dev_dir)

    if args.clear_cache:
        if cache_file.exists():
            cache_file.unlink()
        if mru_file.exists():
            mru_file.unlink()
        sys.exit(0)

    repos = find_git_repos(args.dev_dir, args.no_cache)
    if not repos:
        sys.exit(1)

    display_to_path = {}
    display_list = []

    for repo in repos:
        display = (
            str(Path(repo).relative_to(args.dev_dir))
            if repo.startswith(args.dev_dir)
            else repo
        )
        display_list.append(display)
        display_to_path[display] = repo

    sorted_list = sort_by_mru(display_list, args.dev_dir)
    selected_display = run_menu(sorted_list)

    if not selected_display:
        sys.exit(0)

    clean = selected_display.replace("⭐ ", "", 1)
    selected = display_to_path.get(clean)
    if not selected or not Path(selected).is_dir():
        sys.exit(0)

    update_mru(clean, args.dev_dir)

    project_name = get_project_name(selected)
    session_name = f"dev-{project_name}"
    class_name = f"com.mzunino.dev.{project_name}"

    focus_or_launch_alacritty(class_name, project_name, selected, session_name)


if __name__ == "__main__":
    main()