# /// script
# requires-python = ">=3.12"
# dependencies = ["copier>=9.10", "questionary>=2.1"]
# ///
import argparse
import os
import re
import subprocess
import sys
from pathlib import Path

import questionary
from copier import run_copy, run_update

SOURCE = os.environ.get("TEMPLATES_DIR", "https://git.kotikot.com/templates")
REF = os.environ.get("TEMPLATES_REF")
BACKENDS = {"python": "backend-python"}
FRONTENDS = {"svelte": "frontend-svelte"}
SERVE = ["bun", "static", "api"]


def template(name: str) -> str:
    local = Path(SOURCE) / name
    return str(local) if local.is_dir() else f"{SOURCE}/{name}.git"


def git_config(key: str) -> str:
    result = subprocess.run(["git", "config", key], capture_output=True, text=True, check=False)
    return result.stdout.strip()


def interactive() -> bool:
    return sys.stdin.isatty()


def ask_text(prompt: str, default: str) -> str:
    return questionary.text(prompt, default=default).unsafe_ask() if interactive() else default


def ask_select(prompt: str, choices: list[str], default: str) -> str:
    if not interactive():
        return default
    return questionary.select(prompt, choices=choices, default=default).unsafe_ask()


def ask_checkbox(prompt: str, choices: list[str], default: list[str]) -> list[str]:
    if not interactive():
        return default
    items = [questionary.Choice(c, checked=c in default) for c in choices]
    return questionary.checkbox(prompt, choices=items).unsafe_ask()


def slugify(name: str) -> str:
    return re.sub(r"[^a-z0-9]", "_", name.lower())


def new(args: argparse.Namespace) -> None:
    dest = Path(args.dest).resolve()
    name = args.name or ask_text("Project name", dest.name)
    slug = args.slug or ask_text("Slug", slugify(name))
    parts = args.parts.split(",") if args.parts else ask_checkbox("Parts", ["backend", "frontend", "caddy"], ["backend", "frontend", "caddy"])
    backend = frontend = None
    if "backend" in parts:
        backend = args.backend or ask_select("Backend", list(BACKENDS), "python")
    if "frontend" in parts:
        frontend = args.frontend or ask_select("Frontend", list(FRONTENDS), "svelte")
    serve = "bun"
    if frontend:
        options = SERVE if backend else SERVE[:-1]
        serve = args.serve or ask_select("Frontend served by", options, "bun")
    stack = [p for p in ("backend", "frontend") if p in parts]
    single = len(stack) == 1
    routes = [r for r, ok in (("api", backend), ("frontend", frontend and serve != "api")) if ok]

    def copy(name: str, data: dict) -> None:
        run_copy(template(name), dest, data=data, unsafe=True, defaults=args.defaults, vcs_ref=REF)

    dest.mkdir(parents=True, exist_ok=True)
    identity = {"project_name": name, "project_slug": slug}
    copy("infra", {"project_name": name, "layout": "single" if single else "parts", "parts": [] if single else stack})
    layout = "root" if single else "part"
    if backend:
        copy(BACKENDS[backend], {**identity, "layout": layout, "serve_spa": serve == "api",
                                 "author_name": git_config("user.name"), "author_email": git_config("user.email")})
    if frontend:
        copy(FRONTENDS[frontend], {**identity, "layout": layout, "serve": serve})
    if "caddy" in parts:
        copy("caddy", {"project_slug": slug, "routes": routes})
    if (dest / "Makefile").is_file():
        subprocess.run(["make", "env"], cwd=dest, check=True)


def git_dirty() -> bool:
    result = subprocess.run(["git", "status", "--porcelain"], capture_output=True, text=True, check=False)
    return bool(result.stdout.strip())


def update_message(answers: Path) -> str:
    """Conventional commit for a template update, with the version it moved to."""
    ref = ""
    for line in answers.read_text(encoding="utf-8").splitlines():
        if line.startswith("_commit:"):
            ref = line.split(":", 1)[1].strip().strip("'\"")
            break
    scope = answers.stem
    return f"chore({scope}): update template to {ref}" if ref else f"chore({scope}): update template"


def update(args: argparse.Namespace) -> None:
    answers = sorted(Path(".copier").glob("*.yml"))
    if args.parts:
        answers = [Path(".copier") / f"{p}.yml" for p in args.parts]
    if not answers:
        sys.exit("no .copier/*.yml here")
    if git_dirty():
        sys.exit("working tree is dirty, commit or stash first")
    for file in answers:
        run_update(".", answers_file=str(file), unsafe=True, overwrite=True,
                   skip_answered=not args.ask, defaults=args.defaults, vcs_ref=REF)
        if git_dirty():
            subprocess.run(["git", "add", "-A"], check=True)
            subprocess.run(["git", "commit", "-qm", update_message(file)], check=True)
            print(f"committed {file.stem} update")


GITEA = os.environ.get("GITEA_URL", "https://git.kotikot.com").rstrip("/")
RENOVATE_FILE = "renovate.jsonc"
RENOVATE_STUB = """{
  "$schema": "https://docs.renovatebot.com/renovate-schema.json",
  "extends": ["local>templates/renovate"]
}
"""
RENOVATE_LABELS = [
    ("renovate", "1f6feb", "Pull request from the Renovate bot"),
    ("wait-3d", "d29922", "Waits three days: the registry has no release timestamp, the age gate merges it"),
    ("deps-code", "7d8590", "Code dependencies: pull requests are collected, nothing merges itself"),
]


def gitea_token() -> str:
    token = os.environ.get("GITEA_TOKEN", "")
    if token:
        return token
    path = Path.home() / ".config/gitea/token"
    if path.exists():
        return path.read_text(encoding="utf-8").strip()
    sys.exit("no Gitea token: set GITEA_TOKEN or write ~/.config/gitea/token")


def gitea(args: argparse.Namespace) -> None:
    """Prepare a Gitea repo for Renovate: labels and the preset stub."""
    import base64
    import json
    import urllib.error
    import urllib.request

    token = gitea_token()

    def call(method: str, path: str, body: dict | None = None):
        request = urllib.request.Request(
            f"{GITEA}/api/v1{path}",
            data=json.dumps(body).encode() if body is not None else None,
            method=method,
            headers={"Authorization": f"token {token}", "Content-Type": "application/json"},
        )
        with urllib.request.urlopen(request, timeout=30) as response:
            raw = response.read()
            return json.loads(raw) if raw else None

    # Gitea happily creates a second label with the same name, so the only way to
    # stay idempotent is to look first.
    existing = {label["name"] for label in call("GET", f"/repos/{args.repo}/labels?limit=100") or []}
    for name, color, description in RENOVATE_LABELS:
        if name in existing:
            print(f"label {name}: already there")
            continue
        call("POST", f"/repos/{args.repo}/labels",
             {"name": name, "color": color, "description": description})
        print(f"label {name}: created")

    try:
        call("GET", f"/repos/{args.repo}/contents/{RENOVATE_FILE}")
        print(f"{RENOVATE_FILE}: already there")
    except urllib.error.HTTPError as error:
        if error.code != 404:
            sys.exit(f"{RENOVATE_FILE}: {error.code} {error.read()[:200]!r}")
        call("POST", f"/repos/{args.repo}/contents/{RENOVATE_FILE}", {
            "content": base64.b64encode(RENOVATE_STUB.encode()).decode(),
            "message": "chore(renovate): extend the shared preset",
        })
        print(f"{RENOVATE_FILE}: created")

    print(
        "\nOne thing is still manual, and it does not happen by itself: the repo has\n"
        "to be added to `repositories` in projects/personal/renovate/renovate-config.js\n"
        "of infra/komodo, and the `renovate` team of its organization needs write\n"
        "access to it. Extending the preset subscribes nothing - the bot only visits\n"
        "repos named in that list."
    )


def main() -> None:
    parser = argparse.ArgumentParser(prog="templates")
    sub = parser.add_subparsers(dest="command", required=True)
    n = sub.add_parser("new", help="Compose a project from templates")
    n.add_argument("dest")
    n.add_argument("--name")
    n.add_argument("--slug")
    n.add_argument("--parts", help="comma-separated: backend,frontend,caddy")
    n.add_argument("--backend", choices=list(BACKENDS))
    n.add_argument("--frontend", choices=list(FRONTENDS))
    n.add_argument("--serve", choices=SERVE)
    n.add_argument("--defaults", action="store_true", help="accept template defaults without asking")
    n.set_defaults(func=new)
    u = sub.add_parser("update", help="Update every part from its template")
    u.add_argument("parts", nargs="*", help="parts to update, default all")
    u.add_argument("--ask", action="store_true", help="ask every question again")
    u.add_argument("--defaults", action="store_true")
    u.set_defaults(func=update)
    g = sub.add_parser("gitea", help="Set a repo up for Renovate: labels and preset stub")
    g.add_argument("repo", help="org/name on Gitea")
    g.set_defaults(func=gitea)
    args = parser.parse_args()
    args.func(args)


if __name__ == "__main__":
    main()