#!/usr/bin/env python3
"""
Tool C — pre-publish SEO validator (theexclusionzone.com, Ghost).

A single-post GATE around the SHARED rule engine in seo_rules.py. It does NOT
re-implement any rule — it calls check_post(), the exact same engine Tool A
(seo_audit.py) runs site-wide, so a threshold change in seo_rules.py changes
both tools at once.

Run it on a draft (or a freshly generated article) BEFORE publishing to catch
the issues we just cleaned up site-wide: long meta_description, empty OG/Twitter,
missing alt, too-few internal links.

Modes:
    python3 seo_validate.py --slug <slug>     # fetch one post (draft OR published) via ghst-en
    python3 seo_validate.py --id <post_id>     # same, by id
    python3 seo_validate.py --json <file>      # validate a post object from a JSON file
                                               #   (raw post dict, or {"posts":[{...}]})

Output: PASS/FAIL per rule group with the specific issue + fix hint.
Exit code: 0 if clean (no actionable violations), 1 if any — so it can gate a
publish workflow. READ-ONLY: never writes to Ghost.
"""
import argparse
import json
import os
import subprocess
import sys
import tempfile

import seo_rules as R

# Display groups, in report order. Each maps to the rule-id prefixes it owns.
GROUPS = [
    ("meta_title",        ("meta_title.",)),
    ("meta_description",  ("meta_description.",)),
    ("custom_excerpt",    ("custom_excerpt.",)),
    ("OG / Twitter",      ("og_title.", "og_description.", "twitter_title.", "twitter_description.")),
    ("feature_image",     ("feature_image.",)),
    ("feature_image_alt", ("feature_image_alt.",)),
    ("internal_links",    ("internal_links.",)),
]


def fetch_one(selector, value):
    """Fetch a single post (draft or published) via ghst-en → post dict.

    selector is 'slug' or 'id'. Redirect to a temp file (a post with html+lexical
    can approach the 64 KB pipe-buffer limit)."""
    fd, path = tempfile.mkstemp(suffix=".json", prefix="seo_validate_")
    os.close(fd)
    try:
        flag = "--slug" if selector == "slug" else ""
        target = value if selector == "slug" else value
        cmd = (f"ghst-en post get {flag} {target} --formats html,lexical --json > {path}"
               if selector == "slug"
               else f"ghst-en post get {target} --formats html,lexical --json > {path}")
        r = subprocess.run(cmd, shell=True, stderr=subprocess.PIPE, text=True)
        if r.returncode != 0:
            sys.exit(f"ghst-en fetch failed for {selector}={value}:\n{r.stderr}")
        data = json.load(open(path))
        return _unwrap(data)
    finally:
        os.unlink(path)


def _unwrap(data):
    if isinstance(data, dict) and "posts" in data:
        return data["posts"][0]
    if isinstance(data, list):
        return data[0]
    return data


def load_json(path):
    return _unwrap(json.load(open(path)))


def validate(post):
    """Run the shared engine and print a per-group PASS/FAIL report.
    Returns the number of actionable (non-INFO) violations."""
    violations = R.check_post(post)
    actionable = [v for v in violations if v.severity > R.INFO]
    info = [v for v in violations if v.severity == R.INFO]

    slug = post.get("slug", "(no slug)")
    status = post.get("status", "?")
    title = post.get("title", "")
    print("=" * 74)
    print(f"  PRE-PUBLISH SEO CHECK — {slug}   [status: {status}]")
    print(f"  {title}")
    print("=" * 74)

    by_prefix = {}
    for v in violations:
        for name, prefixes in GROUPS:
            if any(v.rule.startswith(p) for p in prefixes):
                by_prefix.setdefault(name, []).append(v)
                break

    for name, _ in GROUPS:
        vs = [v for v in by_prefix.get(name, []) if v.severity > R.INFO]
        if not vs:
            print(f"  [PASS] {name}")
        else:
            for v in sorted(vs, key=lambda x: -x.severity):
                hint = f"  → {v.fix}" if v.fix else ""
                print(f"  [FAIL] {name:18} {v.message}{hint}")

    # JSON-LD is handled globally by the Edition-main theme (see seo_rules).
    print(f"  [PASS] JSON-LD            (BlogPosting injected globally by theme)"
          if R.THEME_HANDLES_JSONLD else "  [WARN] JSON-LD not theme-handled")

    for v in info:
        print(f"  [note] {v.message}")

    print("-" * 74)
    if actionable:
        print(f"  RESULT: FAIL — {len(actionable)} issue(s) to fix before publishing.")
    else:
        print("  RESULT: PASS — no actionable SEO issues. Clear to publish.")
    print()
    return len(actionable)


def main():
    ap = argparse.ArgumentParser(description="Pre-publish SEO validator (single post).")
    g = ap.add_mutually_exclusive_group(required=True)
    g.add_argument("--slug")
    g.add_argument("--id")
    g.add_argument("--json", metavar="FILE")
    args = ap.parse_args()

    if args.json:
        post = load_json(args.json)
    elif args.slug:
        post = fetch_one("slug", args.slug)
    else:
        post = fetch_one("id", args.id)

    n = validate(post)
    sys.exit(1 if n else 0)


if __name__ == "__main__":
    main()