1#!/usr/bin/env python3
2"""Deterministic pre-check for pairwise skill revision review."""
3 
4from __future__ import annotations
5 
6import argparse
7import json
8import re
9from pathlib import Path
10from typing import Any
11 
12 
13def section_set(text: str) -> set[str]:
14    return set(re.findall(r"^##\s+(.+)$", text, flags=re.MULTILINE))
15 
16 
17def parse_frontmatter(text: str) -> dict[str, str]:
18    if not text.startswith("---\n"):
19        return {}
20    end = text.find("\n---", 4)
21    if end == -1:
22        return {}
23    result: dict[str, str] = {}
24    for line in text[4:end].splitlines():
25        if ":" in line and not line.startswith(" "):
26            key, value = line.split(":", 1)
27            result[key.strip()] = value.strip().strip('"')
28    return result
29 
30 
31def candidate_metrics(path: Path) -> dict[str, Any]:
32    text = path.read_text(encoding="utf-8")
33    frontmatter = parse_frontmatter(text)
34    sections = section_set(text)
35    words = re.findall(r"[A-Za-z0-9_-]+", text)
36    gotchas = 0
37    if "Gotchas" in sections:
38        gotchas_match = re.search(r"## Gotchas\n(.+?)(?:\n## |\Z)", text, flags=re.DOTALL)
39        if gotchas_match:
40            gotchas = len(re.findall(r"^\d+\.", gotchas_match.group(1), flags=re.MULTILINE))
41    return {
42        "path": str(path),
43        "name": frontmatter.get("name", ""),
44        "description_present": bool(frontmatter.get("description")),
45        "line_count": len(text.splitlines()),
46        "word_count": len(words),
47        "sections": sorted(sections),
48        "gotcha_count": gotchas,
49        "has_references": "References" in sections,
50        "has_integration": "Integration" in sections,
51        "has_guidelines": "Guidelines" in sections,
52    }
53 
54 
55def structural_score(metrics: dict[str, Any]) -> float:
56    score = 0.0
57    if metrics["name"]:
58        score += 0.15
59    if metrics["description_present"]:
60        score += 0.15
61    if metrics["line_count"] <= 500:
62        score += 0.2
63    if metrics["gotcha_count"] >= 3:
64        score += 0.15
65    if metrics["has_guidelines"]:
66        score += 0.1
67    if metrics["has_integration"]:
68        score += 0.1
69    if metrics["has_references"]:
70        score += 0.05
71    if metrics["line_count"] <= 300:
72        score += 0.1
73    return round(score, 3)
74 
75 
76def main() -> int:
77    parser = argparse.ArgumentParser(description="Compare two skill revisions before rubric review")
78    parser.add_argument("candidate_a", type=Path)
79    parser.add_argument("candidate_b", type=Path)
80    parser.add_argument("--json", action="store_true")
81    args = parser.parse_args()
82 
83    a = candidate_metrics(args.candidate_a)
84    b = candidate_metrics(args.candidate_b)
85    a["structural_score"] = structural_score(a)
86    b["structural_score"] = structural_score(b)
87    shared_sections = sorted(set(a["sections"]) & set(b["sections"]))
88    section_delta = {
89        "only_a": sorted(set(a["sections"]) - set(b["sections"])),
90        "only_b": sorted(set(b["sections"]) - set(a["sections"])),
91        "shared": shared_sections,
92    }
93 
94    if a["structural_score"] > b["structural_score"]:
95        recommendation = "A"
96    elif b["structural_score"] > a["structural_score"]:
97        recommendation = "B"
98    elif a["line_count"] < b["line_count"]:
99        recommendation = "A"
100    elif b["line_count"] < a["line_count"]:
101        recommendation = "B"
102    else:
103        recommendation = "human_review"
104 
105    result = {
106        "candidate_a": a,
107        "candidate_b": b,
108        "section_delta": section_delta,
109        "deterministic_recommendation": recommendation,
110        "note": "Use researcher/rubrics/pairwise-skill-revision.md for final semantic judgment.",
111    }
112    if args.json:
113        print(json.dumps(result, indent=2))
114    else:
115        print(f"Recommendation: {recommendation}")
116        print(f"A score={a['structural_score']} lines={a['line_count']} gotchas={a['gotcha_count']}")
117        print(f"B score={b['structural_score']} lines={b['line_count']} gotchas={b['gotcha_count']}")
118    return 0
119 
120 
121if __name__ == "__main__":
122    raise SystemExit(main())
123