"""
Command-line interface for frontier-check.

Usage:
    frontier-check "claim text"
    frontier-check -                      # read claim from stdin
    echo "claim" | frontier-check -
    frontier-check --json "claim"
    frontier-check --strict "claim"
    frontier-check --selftest
"""

from __future__ import annotations

import argparse
import json
import sys
from dataclasses import asdict

from .model import Claim, frontier_check, self_test


def _result_to_json(result) -> dict:
    return {
        "claim": result.claim.text,
        "status": result.assessment.status,
        "reason": result.assessment.reason,
        "theorem_used": result.assessment.theorem_used or None,
        "papers": [
            {"title": p.title, "year": p.year, "on_target": p.on_target}
            for p in result.papers
        ],
        "sub_claims": [
            {"kind": s.kind, "text": s.text,
             "verdict": s.verdict or None,
             "evidence": s.evidence or None}
            for s in result.sub_claims
        ],
        "verdict": result.verdict,
        "action": result.action,
        "residual": result.residual,
    }


def _render(result) -> str:
    lines = []
    lines.append("=" * 72)
    lines.append(f"CLAIM: {result.claim.text}")
    lines.append("=" * 72)

    a = result.assessment
    lines.append(f"  [1] Status : {a.status}")
    lines.append(f"      {a.reason}")
    if a.theorem_used:
        lines.append(f"      forbidden by: {a.theorem_used}")

    if result.papers:
        lines.append(f"  [2] Retrieval: {len(result.papers)} paper(s)")
        for p in result.papers:
            flag = "target" if p.on_target else "background"
            lines.append(f"      - [{flag}] {p.title} ({p.year})")
    else:
        lines.append("  [2] Retrieval: none")

    if result.sub_claims:
        lines.append("  [3] Sub-claims:")
        for s in result.sub_claims:
            lines.append(f"      [{s.kind:12s}] {s.text}")
            if s.verdict:
                lines.append(f"                    -> {s.verdict}: "
                             f"{s.evidence}")

    label = "*** FRONTIER ***" if result.verdict == "FRONTIER" else result.verdict
    lines.append(f"  [4] Verdict: {label}")
    if result.action:
        lines.append(f"      action   : {result.action}")
    if result.residual:
        lines.append(f"      residual : {result.residual}")
    return "\n".join(lines)


def main(argv=None) -> int:
    p = argparse.ArgumentParser(
        prog="frontier-check",
        description=(
            "Route LLM claims by their training-data status. "
            "FRONTIER is first-class."
        ),
    )
    p.add_argument(
        "claim",
        nargs="?",
        default=None,
        help="claim text, or '-' to read from stdin",
    )
    p.add_argument(
        "--json",
        action="store_true",
        help="emit JSON instead of a rendered report",
    )
    p.add_argument(
        "--strict",
        action="store_true",
        help="abort with exit code 1 if the self-test fails",
    )
    p.add_argument(
        "--selftest",
        action="store_true",
        help="run the self-test and exit",
    )
    p.add_argument(
        "--quiet",
        action="store_true",
        help="suppress the self-test banner",
    )
    args = p.parse_args(argv)

    # Self-test runs on every invocation.
    if not args.quiet:
        passed, total = self_test(verbose=True)
    else:
        passed, total = self_test(verbose=False)

    if args.selftest:
        return 0 if passed == total else 1

    if args.strict and passed < total:
        print("\n--strict: self-test failed; aborting.", file=sys.stderr)
        return 1

    if args.claim is None:
        p.print_help()
        return 0

    if args.claim == "-":
        claim_text = sys.stdin.read().strip()
    else:
        claim_text = args.claim

    if not claim_text:
        print("empty claim", file=sys.stderr)
        return 1

    result = frontier_check(Claim(claim_text))

    if args.json:
        print(json.dumps(_result_to_json(result), indent=2, ensure_ascii=False))
    else:
        print()
        print(_render(result))

    return 0


if __name__ == "__main__":
    sys.exit(main())