#!/usr/bin/env bash

# shellcheck disable=SC2086

set -e

if [[ $(uname -s) != Linux ]]; then
  printf 'Fuzzing is only supported on Linux\n' >&2
  exit 1
fi

CC=${CC:-clang}
CXX=${CXX:-clang++}

default_fuzz_flags=-fsanitize=fuzzer,address,undefined

export CFLAGS="$default_fuzz_flags $CFLAGS"
export CXXFLAGS="$default_fuzz_flags $CXXFLAGS"

make CC="$CC" CXX="$CXX" libtree-sitter.a

if [[ -z $* ]]; then
  mapfile -t languages < <(ls test/fixtures/grammars)
else
  languages=("$@")
fi

mkdir -p test/fuzz/out

for lang in "${languages[@]}"; do
  # skip typescript & php
  if [[ $lang == typescript || $lang == php ]]; then
    continue
  fi
  printf 'Building %s fuzzer...\n' "$lang"
  lang_dir="test/fixtures/grammars/$lang"
  lang_grammar="${lang_dir}/src/grammar.json"

  # The following assumes each language is implemented as src/parser.c plus an
  # optional scanner in src/scanner.c
  objects=()

  lang_scanner="${lang_dir}/src/scanner"
  if [[ -f "${lang_scanner}.c" ]]; then
    $CC $CFLAGS -std=c11 -g -O1 -I "${lang_dir}/src" -c "${lang_scanner}.c" -o "${lang_scanner}.o"
    objects+=("${lang_scanner}.o")
  fi

  # Compiling with -O0 speeds up the build dramatically
  $CC $CFLAGS -g -O0 -I "${lang_dir}/src" "${lang_dir}/src/parser.c" -c -o "${lang_dir}/src/parser.o"
  objects+=("${lang_dir}/src/parser.o")

  highlights_filename="${lang_dir}/queries/highlights.scm"
  if [[ -f "${highlights_filename}" ]]; then
    ts_lang_query_filename="${lang}.scm"
    cp "${highlights_filename}" "test/fuzz/out/${ts_lang_query_filename}"
  else
    ts_lang_query_filename=""
  fi

  ts_lang="tree_sitter_$(jq -r .name "$lang_grammar")"
  $CXX $CXXFLAGS -std=c++11 -Ilib/include \
    -D TS_LANG="$ts_lang" \
    -D TS_LANG_QUERY_FILENAME="\"${ts_lang_query_filename}\"" \
    test/fuzz/fuzzer.cc \
    "${objects[@]}" \
    libtree-sitter.a \
    -o "test/fuzz/out/${lang}_fuzzer"

  jq '
    [ ..
      | if .type? == "STRING" or (.type? == "ALIAS" and .named? == false) then .value else empty end
      | select(test("\\S") and length == utf8bytelength)
    ] | unique | .[]
  ' "$lang_grammar" | sort > "test/fuzz/out/${lang}.dict"
done