#!/usr/bin/env python3
"""Render a project-specific controller prompt from the reusable template."""

from __future__ import annotations

import argparse
import json
from pathlib import Path
import re
import sys


TEMPLATE = Path(__file__).resolve().parent.parent / "templates/ORCHESTRATOR-PROMPT.template.md"
RUNTIME_DIR = TEMPLATE.parent / "runtime"
PLACEHOLDER = re.compile(r"\{\{([A-Z][A-Z0-9_]*)\}\}")


def render(template: str, profile: dict[str, str]) -> str:
    keys = set(PLACEHOLDER.findall(template))
    missing = sorted(keys - profile.keys())
    if missing:
        raise ValueError("missing profile values: " + ", ".join(missing))
    for key in keys:
        if not isinstance(profile[key], str) or not profile[key].strip():
            raise ValueError(f"{key} must be a nonempty string")
    result = PLACEHOLDER.sub(lambda match: profile[match.group(1)], template)
    if PLACEHOLDER.search(result):
        raise ValueError("profile values must not contain template placeholders")
    return result


def select_runtime(template: str, runtime: str) -> str:
    if runtime == "service":
        return template
    marker = "# 27. HOST CONTROLLER RUNTIME"
    if template.count(marker) != 1:
        raise ValueError("controller runtime section is missing or duplicated")
    prefix = template.split(marker, 1)[0].rstrip()
    overlay = (RUNTIME_DIR / f"{runtime}.md").read_text().strip()
    return prefix + "\n\n" + overlay + "\n"


def main() -> int:
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("profile", type=Path)
    parser.add_argument("--runtime", choices=("service", "terminal"), default="service")
    parser.add_argument("--output", type=Path)
    args = parser.parse_args()
    profile = json.loads(args.profile.read_text())
    if not isinstance(profile, dict):
        parser.error("profile must be a JSON object")
    content = render(select_runtime(TEMPLATE.read_text(), args.runtime), profile)
    if args.output:
        args.output.write_text(content)
        print(args.output)
    else:
        sys.stdout.write(content)
    return 0


if __name__ == "__main__":
    raise SystemExit(main())