#!/usr/bin/env python3
r"""Reproduction check: every token in the transcription must reach the PDF.

The transcription in src/pages is the authority for what the edition should say;
the rendered PDF is what it does say.  A token that appears N times in the source
and fewer than N times in the output is content the typesetter lost.  Comparison
is by bag, not sequence, because endnotes and the Contents move text about.

Found the biblist \hangafter=1 digit-swallowing bug (2026-09-14).

    python3 tools/reprocheck.py [ross-1988-retypeset.pdf]
"""
import re, sys, glob, subprocess, unicodedata
from collections import Counter

PDF = sys.argv[1] if len(sys.argv) > 1 else "ross-1988-retypeset.pdf"

# macros whose text we keep, by which argument(s) carry copy
KEEP = {
    "emph": [0], "textbf": [0], "textit": [0], "textsc": [0], "underline": [0],
    "unsure": [0], "qslip": [0], "erratum": [0],          # \erratum{corrected}{as printed}
    "fn": [1],                                            # \fn{n}{text} - n is a mark
    "plateop": [3], "plate": [2],                         # caption only
    "chapstart": [0], "chaphead": [0], "subhead": [0], "bibgroup": [0], "bibhead": [0],
    "partstart": [0, 1], "sectionstart": [0, 1], "matterstart": [0], "chapnum": [0, 1],
    "pl": [1], "tocl": [2], "toclnp": [2], "pg": [0], "origpage": [0],
    "mbox": [0], "textsuperscript": [0],
}
DROP = {"ig", "fig", "includegraphics", "label", "index", "vspace", "hspace",
        "setlength", "pdfbookmark", "addcontentsline", "input", "hangindent",
        "thispagestyle", "pagestyle", "setstretch", "addmargin", "addvspace",
        "vskip", "hskip", "rule", "makebox", "raisebox", "resizebox", "XeTeXglyph"}

def argspans(s, i):
    """yield (start, end) of consecutive brace groups beginning at i"""
    out = []
    while i < len(s) and s[i] in " \t":
        i += 1
    while i < len(s) and s[i] == "{":
        d, j = 0, i
        while j < len(s):
            if s[j] == "\\":
                j += 2; continue
            if s[j] == "{": d += 1
            elif s[j] == "}":
                d -= 1
                if d == 0:
                    out.append((i + 1, j)); i = j + 1; break
            j += 1
        else:
            break
    return out, i

def detex(s):
    s = re.sub(r"(?<!\\)%.*", "", s)
    out, i = [], 0
    while i < len(s):
        c = s[i]
        if c != "\\":
            out.append(c); i += 1; continue
        m = re.match(r"\\([A-Za-z@]+)\*?", s[i:])
        if not m:
            i += 2
            if s[i - 2:i] == "\\\\":                   # \\[0.6em] - the skip is a length
                k = re.match(r"\s*\[[^\]]*\]", s[i:])
                if k:
                    i += k.end()
            out.append(" "); continue            # \&  \%  \\  ...
        name = m.group(1)
        j = i + m.end()
        while True:                                  # skip [optional] args
            k = s.find("[", j)
            if k != -1 and s[j:k].strip() == "":
                e = s.find("]", k)
                if e == -1:
                    break
                j = e + 1
            else:
                break
        spans, after = argspans(s, j)
        if name in ("begin", "end"):                 # env name and column spec are not copy
            spans = []
        if name == "XeTeXglyph":                     # \XeTeXglyph 824 - unbraced slot id
            k = re.match(r"\s*[0-9]+", s[after:])
            if k:
                after += k.end()
        if name in DROP:
            out.append(" "); i = after; continue
        keep = KEEP.get(name)
        if keep is None:
            out.append(" ")
            for a, b in spans:
                out.append(detex(s[a:b]) + " ")
        else:
            for k in keep:
                if k < len(spans):
                    a, b = spans[k]
                    out.append(" " + detex(s[a:b]) + " ")
        i = after
    return "".join(out)

LIG = {"\ufb00": "ff", "\ufb01": "fi", "\ufb02": "fl", "\ufb03": "ffi", "\ufb04": "ffl"}

def tokens(text):
    text = unicodedata.normalize("NFC", text)
    for k, v in LIG.items():
        text = text.replace(k, v)
    text = text.replace("\u2019", "'").replace("\u2018", "'")
    text = re.sub(r"[\u2010-\u2015]", "-", text)
    return Counter(t.lower() for t in re.findall(r"[0-9]+|[^\W\d_]+", text, re.UNICODE))

src = []
files = sorted(glob.glob("src/pages/p*.tex"))
for f in files:
    src.append(detex(open(f, encoding="utf-8").read()))
A = tokens("\n".join(src))

pdftxt = subprocess.run(["pdftotext", "-layout", PDF, "-"],
                        capture_output=True, text=True).stdout
B = tokens(pdftxt)

where = {}
for f, txt in zip(files, src):
    for t in set(tokens(txt)):
        where.setdefault(t, []).append(f[-8:-4])

# pdftotext merges two tokens wherever the gap is too small to register as a
# space: an endnote superscript onto the word before it (em.55 -> "em55"), and
# the two Bengali forms of a Scheme-of-Transliteration cell. Those are losses in
# the extractor, not in the PDF, and they show up as a token that survives only
# inside a longer one - so report them apart instead of burying the real ones.
# NFD so a precomposed nukta form (U+09DC) still shows its base letter
stream = unicodedata.normalize("NFD", re.sub(r"\s+", " ", pdftxt.lower()))
merged, real = [], []
for t in A:
    if B[t] >= A[t]:
        continue
    row = (A[t] - B[t], t, A[t], B[t])
    probe = unicodedata.normalize("NFD", t)
    (merged if stream.count(probe) >= A[t] else real).append(row)
real.sort(key=lambda r: (-r[0], r[1]))
merged.sort(key=lambda r: (-r[0], r[1]))
deficits = real
print(f"{len(files)} page files, {sum(A.values())} source tokens, "
      f"{sum(B.values())} pdf tokens, {len(real)} tokens short "
      f"({len(merged)} more merged into a neighbour by the extractor)")
for n, t, a, b in deficits:
    pp = where.get(t, [])
    tail = " ".join(pp) if len(pp) <= 8 else " ".join(pp[:8]) + " ..."
    print(f"  -{n:<4} {t!r:24} src {a:<4} pdf {b:<4} p{tail}")
if merged:
    print("extractor merges (not losses):",
          ", ".join(f"{t}(-{n})" for n, t, a, b in merged))