#!/usr/bin/env bash
# Compila o C-Dogs SDL do fredygames.com: o jogo de acao de cima de Ronny Wester (1997) e de Cong Xu e
# colaboradores (codigo GPL-2.0-ou-posterior, com partes BSD/MIT/zlib/ISC) em WebAssembly, com o Emscripten
# 6.0.10 e as portas SDL2, SDL2_image, SDL2_mixer, ogg e vorbis dele, do jeito que o projeto ja faz em
# make_emscripten.sh (IDBFS para configuracao e recordes, ASYNCIFY).
#
#   source <emsdk>/emsdk_env.sh      # emsdk install 6.0.10 && emsdk activate 6.0.10
#   src/FredGames.Bundler/Builds/build-cdogs.sh
#
# Fonte: o commit 9343f5b do repositorio cxong/cdogs-sdl, conferido pelo SHA-256 e guardado em
# artifacts/cache/cdogs/. O script tira dele (e o bundle.yaml tira do fonte hospedado, a mesma lista):
#   - src/cdogs/cwolfmap/: o importador de mapas do Wolfenstein 3D traz o OPL do MAME (fmopl.c), cuja
#     licenca proibe uso comercial; map_wolf_stub.c (cdogs/) ocupa o lugar de map_wolf.c e
#     cdogs-fredygames.patch tira as chamadas a ele de campaign_entry.c e map_new.c;
#   - data/.wolf3d, missions/WOLF3D e doc/license-mame.txt, do mesmo importador;
#   - as campanhas e mapas sem licenca livre registrada: ficam so as de missions/ e dogfights/ que trazem
#     LICENSE.md em CC0 (Sauer2, clovehoof, Cong Xu); as originais de Ronny Wester que outros jogadores
#     mandaram (sem autor, segundo o proprio Wester em doc/README_DATA.md), as copias de jogos comerciais
#     (Doom, Counter-Strike) e as musicas das campanhas sem credito (devhell1.xm, devhell2.ogg,
#     graveintent1.xm) ficam de fora. Os graficos, sons e musicas do jogo trazem credito por arquivo
#     (CC0, CC BY, CC BY-SA), conferidos no LICENSE.txt do jogo.
# sys_config.h, que o CMake geraria, sai do modelo sys_config.h.cmake por sed.
#
# Saida: artifacts/build/cdogs-2.5.0-9343f5b/cdogs.{js,wasm,data}, que o bundle.yaml confere pelo SHA-256.
set -euo pipefail

COMMIT=9343f5b56144f1c4f663db9fb8341c0157917ffa
SRC_SHA256=fb445840847615c09e25c005935aadd9738a72d56aaa7608b850b1bc4bc48c2b
PRUNED_SHA256=8fdbe1318c6c4256fa6556f85a42ac08f03a99616eb1a24f1a284a4883306ca8
EMSCRIPTEN=6.0.10

here="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
root="$(git -C "$here" rev-parse --show-toplevel 2>/dev/null || pwd)"
out="$root/artifacts/build/cdogs-2.5.0-${COMMIT:0:7}"
cache="$root/artifacts/cache/cdogs"
tarball="$cache/cdogs-$COMMIT.tar.gz"

if ! emcc --version 2>/dev/null | head -1 | grep -q " $EMSCRIPTEN "; then
  echo "Precisa do Emscripten $EMSCRIPTEN no PATH (source <emsdk>/emsdk_env.sh)." >&2
  exit 1
fi
aux() { if [ -f "$here/cdogs/$1" ]; then echo "$here/cdogs/$1"; else echo "$here/$1"; fi; }

# Fonte tirado das pastas abaixo: a mesma lista do bundle.yaml (sources.remove).
PRUNE=(
  src/cdogs/cwolfmap data/.wolf3d doc/license-mame.txt missions/WOLF3D missions/custom
  missions/ai_insurgency_2.cdogscpn missions/bem.cdogscpn missions/cyberdogs.cdogscpn
  missions/distress.cdogscpn missions/doom.cdogscpn missions/ogre.cdogscpn missions/Sand.cdogscpn
  missions/terror.cdogscpn missions/zombie.cdogscpn
  missions/devhell1.xm missions/devhell2.ogg missions/graveintent1.xm
  dogfights/cubicle.cdogscpn dogfights/de_dust.cdogscpn dogfights/doom_e1m1.cdogscpn
  dogfights/dungeon.cdogscpn dogfights/dwango5_map01.cdogscpn dogfights/map07.cdogscpn
  dogfights/temple_of_carnage.cdogscpn
)

# O site hospeda o mesmo commit ja sem as pastas de PRUNE (cdogs-9343f5b.tar.gz, ao lado deste script); o
# script aceita os dois. Tirar o que ja nao esta la nao faz nada.
if [ -f "$here/cdogs-${COMMIT:0:7}.tar.gz" ]; then
  tarball="$here/cdogs-${COMMIT:0:7}.tar.gz"
  echo "$PRUNED_SHA256  $tarball" | shasum -a 256 -c - >&2
else
  if [ ! -f "$tarball" ]; then
    mkdir -p "$cache"
    curl -fsSL -o "$tarball.part" "https://github.com/cxong/cdogs-sdl/archive/$COMMIT.tar.gz"
    mv "$tarball.part" "$tarball"
  fi
  echo "$SRC_SHA256  $tarball" | shasum -a 256 -c - >&2
fi

rm -rf "$out"
mkdir -p "$out/work/obj" "$out/work/src"
S="$out/work/src"
tar xzf "$tarball" -C "$S" --strip-components=1
for p in "${PRUNE[@]}"; do rm -rf "${S:?}/$p"; done
patch -d "$S" -p1 --no-backup-if-mismatch < "$(aux cdogs-fredygames.patch)" >&2
cp "$(aux map_wolf_stub.c)" "$S/src/cdogs/map_wolf_stub.c"
sed -e 's|@VERSION@|2.5.0|; s|@CDOGS_DATA_DIR@|./|; s|@CDOGS_CFG_DIR@|.config/cdogs-sdl/|' \
  "$S/src/cdogs/sys_config.h.cmake" > "$S/src/cdogs/sys_config.h"

# O yajl espera seus cabecalhos publicos em <yajl/...>, que o CMake do projeto copia; o yajl_version.h
# sai do modelo (yajl 2.1.1).
mkdir -p "$out/work/inc/yajl"
cp "$S"/src/cdogs/yajl/api/yajl_{parse,gen,common,tree}.h "$out/work/inc/yajl/"
sed -e 's|${YAJL_MAJOR}|2|g; s|${YAJL_MINOR}|1|g; s|${YAJL_MICRO}|1|g' \
  "$S/src/cdogs/yajl/api/yajl_version.h.cmake" > "$out/work/inc/yajl/yajl_version.h"

PORTS=(-sUSE_SDL=2 -sUSE_SDL_IMAGE=2 -sSDL2_IMAGE_FORMATS='["png"]' -sUSE_SDL_MIXER=2
  -sSDL2_MIXER_FORMATS='["ogg"]' -sUSE_VORBIS=1 -sUSE_OGG=1)
FLAGS=(-O2 -w -D PB_FIELD_16BIT=1 -D YAJL_BUILD -ffile-prefix-map="$out/work/="
  -I"$S/src" -I"$S/src/cdogs" -I"$S/src/proto/nanopb" -I"$S/src/cdogs/enet/include"
  -I"$S/src/cdogs/include" -I"$out/work/inc" "${PORTS[@]}")

srcs=()
while IFS= read -r f; do srcs+=("$f"); done < <(
  { ls "$S"/src/*.c; find "$S/src/cdogs" -name '*.c' ! -name map_wolf.c; ls "$S"/src/base64/base64.c "$S"/src/json/*.c "$S"/src/proto/*.c \
    "$S"/src/proto/nanopb/*.c; } | LC_ALL=C sort)
objs=()
for f in "${srcs[@]}"; do
  rel="${f#"$S/"}"
  o="$out/work/obj/${rel//\//_}.o"
  objs+=("$o")
  emcc "${FLAGS[@]}" -c "$f" -o "$o"
done

# Dados: so o que o jogo le, nas pastas de sempre; liga de dentro da pasta de saida com caminhos relativos.
mkdir -p "$out/doc"
cp -R "$S/data" "$S/graphics" "$S/music" "$S/sounds" "$S/missions" "$S/dogfights" "$out/"
cp "$S/doc/CREDITS" "$S/doc/AUTHORS" "$out/doc/"
find "$out" -name .DS_Store -delete
(
  cd "$out"
  emcc -O2 "${objs[@]}" "${PORTS[@]}" -lidbfs.js \
    -sASYNCIFY -sSTACK_SIZE=2097152 -sINITIAL_MEMORY=128mb -sALLOW_MEMORY_GROWTH=1 -sENVIRONMENT=web \
    -sEXPORTED_RUNTIME_METHODS=FS \
    --preload-file data --preload-file doc --preload-file dogfights --preload-file graphics \
    --preload-file missions --preload-file music --preload-file sounds \
    -o cdogs.js
)
rm -rf "$out/work" "$out/data" "$out/doc" "$out/dogfights" "$out/graphics" "$out/missions" "$out/music" "$out/sounds"

shasum -a 256 "$out/cdogs.js" "$out/cdogs.wasm" "$out/cdogs.data"