#!/usr/bin/env python3
"""
Repair pass: fix HTML references that point at files which exist under a
different (shorter/aliased) name on disk. Drupal style-derived images are
referenced by long decorative names (e.g. 68997caf12e42-Mitsubishi+Attrage+
....jpg) but the actual downloaded file uses the base id (68997caf12e42.jpg).

For each unresolvable local reference, try:
  1. Match by (dir, base-id-before-minus/plus, ext)  -> existing file
  2. Match by (dir, full stem, ext)
If found, rewrite the reference to the existing file.
"""
import os, re, sys, urllib.parse

sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
from common import OUT_DIR


def build_file_index():
    index = {}
    for dirpath, dirnames, filenames in os.walk(OUT_DIR):
        for fn in filenames:
            if fn == "index.html":
                continue
            rel = os.path.relpath(os.path.join(dirpath, fn), OUT_DIR)
            stem = os.path.splitext(fn)[0]
            ext = os.path.splitext(fn)[1].lower()
            d = os.path.normpath(dirpath)
            index[(d, stem.lower(), ext)] = rel
            baseid = re.split(r'[-+]', stem)[0]
            if len(baseid) >= 6:
                index.setdefault((d, baseid, ext), rel)
    return index


def repair():
    index = build_file_index()
    print(f"Indexed {len(index)} asset aliases.")
    all_missing = 0
    fixed = 0
    for dirpath, dirnames, filenames in os.walk(OUT_DIR):
        if "index.html" not in filenames:
            continue
        fpath = os.path.join(dirpath, "index.html")
        with open(fpath, encoding="utf-8") as f:
            html = f.read()
        changed = False

        def fix_ref(m):
            nonlocal all_missing, fixed, changed
            prefix, u = m.group(1), m.group(2)
            upath = u.split("?")[0].split("#")[0]
            if not upath or upath.startswith(("http", "data:", "mailto:", "tel:",
                                              "javascript:", "//", "#")):
                return m.group(0)
            target = os.path.normpath(os.path.join(dirpath, upath))
            if os.path.exists(target):
                return m.group(0)
            all_missing += 1
            tdir = os.path.dirname(target)
            tstem = os.path.splitext(os.path.basename(target))[0]
            text = os.path.splitext(os.path.basename(target))[1].lower()
            baseid = re.split(r'[-+]', tstem)[0]
            cand = None
            if baseid and len(baseid) >= 6:
                cand = index.get((os.path.normpath(tdir), baseid, text))
            if cand is None:
                cand = index.get((os.path.normpath(tdir), tstem.lower(), text))
            if cand:
                newu = os.path.relpath(os.path.join(OUT_DIR, cand), dirpath).replace(os.sep, "/")
                fixed += 1
                changed = True
                q = "?" + u.split("?")[1] if "?" in u else ""
                h = "#" + u.split("#")[1] if "#" in u else ""
                return prefix + newu + q + h
            return m.group(0)

        html = re.sub(r'(src|href)="([^"]*)"', fix_ref, html)
        if changed:
            with open(fpath, "w", encoding="utf-8") as f:
                f.write(html)
    print(f"Total unresolvable local refs: {all_missing}; fixed {fixed}.")


if __name__ == "__main__":
    repair()