#!/usr/bin/env python3
"""Regenerate a vendored copy of the dashboard UI for an app that embeds it.

Sanad's "Hands" tab serves a CODE COPY of this dashboard's HTML with every /api/
call rewritten to /api/hands/, and proxies those calls back to :8088. A hand copy
goes stale the moment hand_web.py changes — a button appears here and not there,
and nobody notices until it is needed. This regenerates that copy from the real
source, so re-vendoring is one command instead of an extraction by hand.

    # write Sanad's copy (run after any dashboard change, then redeploy Sanad)
    python3 tools/export_ui.py --prefix hands \
        --out ~/Sanad_Package_5/Sanad/dashboard/static/hands.html

    # check an existing copy is current, without writing (exit 1 if stale)
    python3 tools/export_ui.py --prefix hands --check <path>

The HTML is taken from hand_web.py itself rather than re-parsed from a file, so
what gets vendored is exactly what the server serves.
"""
import argparse
import os
import re
import sys

HERE = os.path.dirname(os.path.abspath(__file__))
sys.path.insert(0, os.path.join(HERE, "..", "web"))


def build(prefix):
    import hand_web                                    # noqa: E402  (path set above)
    html = hand_web.HTML
    if not prefix:
        return html
    # Only rewrite the API root. Absolute URLs that merely contain "api" (there are
    # none today, but a future /api/... inside a string literal would be caught by
    # the same rule) go through unchanged unless they start a request path.
    out, n = re.subn(r"(?<![\w/])/api/", "/api/%s/" % prefix.strip("/"), html)
    if not n:
        sys.exit("no /api/ references found — has the dashboard HTML moved?")
    return out


def main():
    ap = argparse.ArgumentParser(description="Export the dashboard UI for embedding")
    ap.add_argument("--prefix", default="hands",
                    help="proxy prefix the host app serves (default: hands -> /api/hands/)")
    ap.add_argument("--out", help="write here (default: stdout)")
    ap.add_argument("--check", metavar="PATH",
                    help="compare against PATH and exit 1 if it is stale")
    a = ap.parse_args()
    html = build(a.prefix)

    if a.check:
        try:
            cur = open(a.check, encoding="utf-8").read()
        except OSError as e:
            sys.exit("cannot read %s: %s" % (a.check, e))
        if cur == html:
            print("up to date: %s" % a.check)
            return
        print("STALE: %s (%d bytes) differs from the current dashboard (%d bytes)"
              % (a.check, len(cur), len(html)))
        sys.exit(1)

    if a.out:
        with open(a.out, "w", encoding="utf-8") as f:
            f.write(html)
        print("wrote %s (%d bytes, prefix /api/%s/)" % (a.out, len(html), a.prefix))
    else:
        sys.stdout.write(html)


if __name__ == "__main__":
    main()