#!/usr/bin/env python3
"""Regenerate the used-only iconify subset stylesheet.

The full `src/Public/assets/admin/vendor/fonts/iconify-icons.css` ships ~5900
Tabler icons (2.6 MB) but the panel references only ~150 of them. This scans
the PHP/JS/CSS source for literal `tabler-*` class tokens and writes a minified
`iconify-icons.min.css` next to the full file, containing just the base `.ti`
rule plus the icon rules that are actually used. Both admin and reseller shells
link the `.min.css`.

Run it after adding a NEW tabler-* icon anywhere in the source:

    python3 tools/generate-iconify-subset.py

Paths are resolved by locating the repo's `src/` root above this file, so it
works from any CWD. Only literal `tabler-foo` tokens are detected — never build
icon class names dynamically (e.g. "tabler-" + name) or the subset will miss
them.
"""

import os
import re
import sys

HERE = os.path.dirname(os.path.abspath(__file__))

# Locate the application `src/` root (repo-root/src). tools/ sits beside src/.
SRC_ROOT = os.path.join(os.path.dirname(HERE), "src")
if not os.path.isdir(SRC_ROOT):
    # Fallback: ascend until a `src/` directory is found.
    node = HERE
    while node != os.path.dirname(node):
        cand = os.path.join(node, "src")
        if os.path.isdir(cand):
            SRC_ROOT = cand
            break
        node = os.path.dirname(node)

FONTS_DIR = os.path.join(SRC_ROOT, "Public", "assets", "admin", "vendor", "fonts")
SRC = os.path.join(FONTS_DIR, "iconify-icons.css")
DST = os.path.join(FONTS_DIR, "iconify-icons.min.css")

# Source trees to scan for icon usage, relative to the `src/` root.
SCAN_DIRS = ["Public/Views", "Public/assets/admin/js", "Public/assets/admin/xcvm", "Core", "Modules"]
SCAN_EXTS = (".php", ".js", ".css")

TOKEN_RE = re.compile(r"tabler-[a-z0-9\-]+")
RULE_RE = re.compile(r"\.([a-zA-Z0-9_\-]+)\s*\{(.*?)\}", re.S)


def collect_used_tokens():
    """Return the set of literal tabler-* tokens referenced in the source."""
    used = set()
    for rel in SCAN_DIRS:
        base = os.path.join(SRC_ROOT, rel)
        for root, _dirs, files in os.walk(base):
            for name in files:
                if not name.endswith(SCAN_EXTS) or name.startswith("iconify-icons"):
                    continue
                try:
                    text = open(os.path.join(root, name), encoding="utf-8", errors="replace").read()
                except OSError:
                    continue
                used.update(TOKEN_RE.findall(text))
    return used


def minify_block(body):
    """Collapse whitespace in a rule body, preserving quoted url("...") data."""
    out = []
    in_str = False
    quote = ""
    pending = False
    prev = ""
    for c in body:
        if in_str:
            out.append(c)
            if c == quote:
                in_str = False
            continue
        if c in "\"'":
            in_str = True
            quote = c
            out.append(c)
            prev = c
            pending = False
            continue
        if c in " \t\r\n\f":
            pending = True
            continue
        if c in ":;,":
            pending = False
            out.append(c)
            prev = c
            continue
        if pending:
            if prev and prev not in ":;,(":
                out.append(" ")
            pending = False
        out.append(c)
        prev = c
    return "".join(out).strip()


def main():
    if not os.path.isfile(SRC):
        sys.exit("source not found: %s" % SRC)

    used = collect_used_tokens()
    css = open(SRC, encoding="utf-8").read()

    base = None
    kept = []
    kept_names = set()
    for m in RULE_RE.finditer(css):
        selector, body = m.group(1), minify_block(m.group(2))
        if selector == "ti":
            base = ".ti{" + body + "}"
        elif selector in used:
            kept.append("." + selector + "{" + body + "}")
            kept_names.add(selector)

    missing = sorted(used - kept_names - {"ti"})
    if missing:
        # Not fatal: tokens matched in source but absent from the full css
        # (typos, or icons from another set). Report so they can be fixed.
        sys.stderr.write("warning: %d referenced icon(s) not in %s:\n  %s\n" % (
            len(missing), os.path.basename(SRC), ", ".join(missing)))

    if base is None:
        sys.exit("base `.ti` rule not found in source css")

    header = (
        "/* Generated by tools/generate-iconify-subset.py — do not edit by hand.\n"
        "   Used-only subset of iconify-icons.css. Icons: %d.\n"
        "   Re-run the script after adding a new tabler-* icon. */\n" % len(kept)
    )
    open(DST, "w", encoding="utf-8").write(header + base + "\n" + "".join(kept) + "\n")

    orig = os.path.getsize(SRC)
    sub = os.path.getsize(DST)
    print("icons kept : %d" % len(kept))
    print("subset     : %s" % DST)
    print("size       : %.1f KB (-%.1f%% vs full %.1f MB)" % (
        sub / 1024, 100 * (1 - sub / orig), orig / 1024 / 1024))


if __name__ == "__main__":
    main()