"""Serialize translatable blocks into compact marker templates.

Marker scheme (short => cheap to reproduce while translating):
   <n/>       opaque inline element (code / img / kbd / abbr-with-code-text) - kept verbatim
   <l n>..</l> link (<a>): inner text is translatable, anchor markup is restored later
   <b>..</b>   <strong>
   <i>..</i>   <em>
   everything else inline is transparent (unwrapped) but its text is translatable
"""
import json, re, sys
from bs4 import BeautifulSoup, NavigableString, Comment

SRC = r"C:/Users/yvmou/Downloads/limboai-readthedocs-io-en-stable/limboai-stable/index.html"
OUT = r"C:/Users/yvmou/Downloads/limboai-readthedocs-io-en-stable/limboai-stable/_i18n/blocks.json"

BLOCK_TAGS = {"p", "h1", "h2", "h3", "h4", "h5", "h6", "td", "th", "dt", "dd",
              "figcaption", "caption", "li"}
OPAQUE = {"code", "kbd", "samp", "var", "tt", "img", "pre", "script", "style", "math"}
TRANSPARENT = {"span", "cite", "markdown", "mark", "small", "sub", "sup", "u", "s", "q"}


class Ser:
    def __init__(self):
        self.markers = {}
        self.n = 0

    def add(self, html):
        self.n += 1
        self.markers[str(self.n)] = html
        return self.n

    def walk(self, node, out):
        for ch in node.children:
            if isinstance(ch, Comment):
                continue
            if isinstance(ch, NavigableString):
                s = re.sub(r"\s+", " ", str(ch))
                if s:
                    out.append(s)
                continue
            name = ch.name
            cls = ch.get("class") or []
            if name == "a" and "headerlink" in cls:
                continue
            if name in OPAQUE or name == "abbr":
                out.append("<%d/>" % self.add(str(ch)))
                continue
            if name in TRANSPARENT:
                self.walk(ch, out)
                continue
            if name == "a":
                idx = self.add(str(ch))
                out.append("<l%d>" % idx)
                self.walk(ch, out)
                out.append("</l>")
                continue
            if name == "strong":
                out.append("<b>")
                self.walk(ch, out)
                out.append("</b>")
                continue
            if name in ("em", "dfn"):
                out.append("<i>")
                self.walk(ch, out)
                out.append("</i>")
                continue
            self.walk(ch, out)

    def run(self, tag):
        out = []
        self.walk(tag, out)
        tpl = "".join(out)
        tpl = re.sub(r"[ \t]*\n[ \t]*", "\n", tpl)
        tpl = re.sub(r"\n{2,}", "\n", tpl).strip()
        return tpl


def serialize(node, kind, feed):
    s = Ser()
    tpl = s.run(node)
    if not re.search(r"[A-Za-z]", re.sub(r"<[^>]*>", "", tpl)):
        return
    feed.append({"kind": kind, "tag": node.name, "tpl": tpl, "markers": s.markers,
                 "node": node})


def collect(soup):
    """Walk the document exactly the way the extractor did."""
    feed = []
    body = soup.find("div", {"role": "main"})
    for node in body.find_all(True):
        if node.name not in BLOCK_TAGS:
            continue
        if node.name == "li" and node.find("p", recursive=False):
            continue
        for p in node.parents:
            if getattr(p, "name", None) in ("pre", "code"):
                break
        else:
            serialize(node, "body", feed)
    for cap in soup.select("p.caption span.caption-text"):
        serialize(cap, "nav", feed)
    for a in soup.select("div.wy-menu a, nav a"):
        if a.find_parent("div", class_="wy-menu") is None:
            continue
        serialize(a, "nav", feed)
    return feed


if __name__ == "__main__":
    blocks = collect(BeautifulSoup(open(SRC, encoding="utf-8").read(), "lxml"))
    plain = [{"kind": b["kind"], "tag": b["tag"], "path": "", "html": b["tpl"],
              "text": re.sub(r"<[^>]*>", "", b["tpl"]), "markers": b["markers"]}
             for b in blocks]
    json.dump(plain, open(OUT, "w", encoding="utf-8"), ensure_ascii=False, indent=1)
    uniq = {}
    for b in blocks:
        uniq.setdefault(b["tpl"] + "\x00" + json.dumps(b["markers"], sort_keys=True), b)
    print("blocks:", len(blocks), "unique:", len(uniq),
          "unique tpl chars:", sum(len(b["tpl"]) for b in uniq.values()))