#!/usr/bin/env bash
# Rebuilds app/assets/fonts/nerd_icons.ttf.
#
# ai-app draws its icons as glyphs in a Nerd Fonts subset it ships, rather
# than as ordinary Unicode out of whatever the platform resolved. Unicode's
# own geometric shapes are what this replaced: `tool.rs` set its disclosure
# mark with U+25B8/25BE/25B4, and once iris stopped bundling fonts
# (2026-09-07) Iris's phone drew an empty box for them and this VM drew a
# dot. UI_RULES: "don't rely on characters the platform might not have --
# ship the glyph or the asset rather than hoping."
#
# The whole symbols font is 3 MB for the handful below, so what is
# committed is a subset. Add a codepoint to GLYPHS *and* to
# `app/src/ui/icon.rs` (the two lists have to agree -- a codepoint in
# the Rust that this script did not subset is a glyph that silently isn't
# there), then run this and commit the result.
#
# Needs python3 and network access; fontTools is fetched into a temporary
# venv, so nothing has to be installed on the machine.
#
# The Mono face makes icon metrics stable; the Material Design family keeps
# their meanings conventional.
set -euo pipefail

GLYPHS=(
    U+F035D  # md-menu_down -- a card that is open
    U+F035F  # md-menu_right -- a card that opens
    U+F0360  # md-menu_up -- collapse this group again
)

url=https://github.com/ryanoasis/nerd-fonts/releases/latest/download/NerdFontsSymbolsOnly.zip
here="$(cd "$(dirname "$0")" && pwd)"
out="$here/assets/fonts/nerd_icons.ttf"
work="$(mktemp -d)"
trap 'rm -rf "$work"' EXIT

echo "Fetching $url"
curl -fsSL -o "$work/nf.zip" "$url"
python3 -c 'import sys,zipfile; zipfile.ZipFile(sys.argv[1]).extractall(sys.argv[2])' "$work/nf.zip" "$work"

python3 -m venv "$work/venv"
"$work/venv/bin/pip" -q install fonttools

unicodes="$(IFS=,; echo "${GLYPHS[*]}")"
mkdir -p "$(dirname "$out")"
# The Mono face, where every glyph is one em wide and one em tall, so two
# icons at the same font size are the same size without either being given
# one, which makes an icon's box predictable beside a line of text.
"$work/venv/bin/pyftsubset" "$work/SymbolsNerdFontMono-Regular.ttf" \
    --unicodes="$unicodes" \
    --layout-features= \
    --drop-tables+=DSIG \
    --output-file="$out"
cp "$work/LICENSE" "$here/assets/fonts/NERD_FONTS_LICENSE.txt"

echo "Wrote $out ($(stat -c %s "$out") bytes) with ${#GLYPHS[@]} glyphs"