#!/usr/bin/env bash
#
# Refresh resources/svg/symbols from google/material-design-icons (Apache-2.0).
#
# Material Symbols Rounded at weight 400 and grade 0, outlined and filled, in two cuts:
# optical size 24 (the standard size) and optical size 20. M3 draws an icon at 20 dp or
# smaller from the 20 cut, whose strokes stay as heavy as the 24 dp design's instead of
# thinning as the glyph is scaled down (docs/reference/m3/styles.md § Icons, the optical
# size axis). Maintenance only: applications never run this, and bin/ is not part of the
# archive Composer installs.
#
# The repository is ~5 GB, so it is cloned without blobs and checked out sparsely:
# git downloads only the four files per symbol that are kept. The @material-symbols
# npm packages were not used because their SVGs are drawn at optical size 48, whose
# strokes are thinner than the 24px design.

set -euo pipefail

root="$(cd "$(dirname "$0")/.." && pwd)"
work="$(mktemp -d)"
trap 'rm -rf "$work"' EXIT

git clone --quiet --depth=1 --filter=blob:none --no-checkout \
    https://github.com/google/material-design-icons.git "$work/repo"

cd "$work/repo"

git sparse-checkout set --no-cone \
    '/symbols/web/*/materialsymbolsrounded/*_24px.svg' \
    '/symbols/web/*/materialsymbolsrounded/*_20px.svg' \
    '!/symbols/web/*/materialsymbolsrounded/*_wght[0-9]*' \
    '!/symbols/web/*/materialsymbolsrounded/*_grad200*' \
    '!/symbols/web/*/materialsymbolsrounded/*_gradN25*'

git checkout --quiet "$(git symbolic-ref --short HEAD)"

out="$root/resources/svg/symbols"

# The 24 cut keeps the folder names it has always had; the 20 cut is suffixed, so a
# name resolves to a folder without a lookup table (Support\SvgFile::symbol()).
folder() { # optical size, style
    case "$1" in
        24) echo "$out/$2" ;;
        *) echo "$out/$2-$1" ;;
    esac
}

for size in 24 20; do
    for style in outlined filled; do
        rm -rf "$(folder "$size" "$style")"
        mkdir -p "$(folder "$size" "$style")"
    done
done

# Google's files carry width="24" height="24" and no fill. Drop the size so CSS decides
# it, and paint in currentColor so an icon takes the colour of the text around it.
normalise() {
    sed -E \
        -e 's/ (width|height)="[0-9]+(px)?"//g' \
        -e 's/<svg /<svg fill="currentColor" /' \
        "$1"
}

missing=0

for dir in symbols/web/*/materialsymbolsrounded; do
    name="$(basename "$(dirname "$dir")")"

    for size in 24 20; do
        outlined="$dir/${name}_${size}px.svg"
        filled="$dir/${name}_fill1_${size}px.svg"

        if [[ ! -f "$outlined" || ! -f "$filled" ]]; then
            echo "skipped $name: no outlined and filled ${size}px pair" >&2
            missing=$((missing + 1))
            continue
        fi

        normalise "$outlined" > "$(folder "$size" outlined)/$name.svg"
        normalise "$filled" > "$(folder "$size" filled)/$name.svg"
    done
done

git rev-parse HEAD > "$out/SOURCE"

echo "$(ls "$out/outlined" | wc -l | tr -d ' ') symbols at optical size 24 and $(ls "$out/outlined-20" | wc -l | tr -d ' ') at 20 from google/material-design-icons@$(cut -c1-12 "$out/SOURCE"), $missing skipped"