#!/usr/bin/env bash

set -o errexit
set -o nounset
set -o pipefail
if [[ "${TRACE-0}" == "1" ]]; then
    set -o xtrace
fi

zig_root="$HOME/.zig"

prompt_confirm() {
  while true; do
    read -r -n 1 -p "${1:-Continue?} [y/n]: " REPLY
    case $REPLY in
      [yY]) echo ; return 0 ;;
      [nN]) echo ; return 1 ;;
      *) printf " \033[31m %s \n\033[0m" "invalid input"
    esac
  done
}


help() {
    echo "Usage: $0

    Install/update zig and zls under ~/.zig

"
    exit
}

install_zig() {
    arch="x86_64-linux"
    zig_master_arch_json="$(jq -r ".\"$arch\"" <<< "$zig_master_json")"
    zig_master_tarball="$(jq -r '.tarball' <<< "$zig_master_arch_json")"
    zig_master_shasum="$(jq -r '.shasum' <<< "$zig_master_arch_json")"
    zig_master_size="$(jq -r '.size' <<< "$zig_master_arch_json")"

    echo "$zig_master_tarball"
    echo "$zig_master_shasum"
    echo "$zig_master_size"

    if [ ! -d "$zig_root/tmp" ]; then
      mkdir "$zig_root/tmp"
    fi

    echo "fetching tarball"
    zig_tarball_path="$zig_root/tmp/zig.tar"
    wget -O "$zig_root/tmp/zig.tar" "$zig_master_tarball"

    if ! echo "$zig_master_shasum $zig_tarball_path" | sha256sum --check; then
      echo "invalid tarball; bailing"
      exit 1
    fi

    echo "extracting tarball"

    if [ ! -d "$zig_root/zig" ]; then
      mkdir "$zig_root/zig"
    fi

   if ! tar -xf "$zig_tarball_path" -C "$zig_root/zig" --strip-components=1 ; then
     echo "extraction failed; bailing"
     exit 1
   fi

   echo "zig installed"
    zig version
}

install_zls() {
   zls_path="$zig_root/zls"
   if [ ! -d "$zls_path" ]; then
     echo "cloning zls"
     git clone https://github.com/zigtools/zls.git "$zls_path" --depth 1 --single-branch --branch master
   fi
   cd "$zls_path"
   echo "fetching zls"
   git pull
   echo "building zls"
   zig build -Doptimize=ReleaseSafe

    if [ ! -d "$zig_root/bin" ]; then
      mkdir "$zig_root/bin"
    fi

    cp "$zls_path/zig-out/bin/zls" "$zig_root/bin"
    echo "zls installed"
    zls --version
}

if [[ "${1-}" =~ ^-*h(elp)?$ ]]; then
    help
fi

cd "$(dirname "$0")"

main() {
  # Transform long options to short ones
  for arg in "$@"; do
    shift
    case "$arg" in
      '--force')     set -- "$@" '-f'   ;;
      *)             set -- "$@" "$arg" ;;
    esac
  done
    force=0
    while getopts "f" o; do
      case "${o}" in
        f)
          force=1
          ;;
        *)
          echo "invalid flag"
          help
          ;;
      esac
    done

    if [ ! -d "$zig_root" ]; then
      echo "initalizing zig directory"
      mkdir "$zig_root"
      # shellcheck disable=SC2016
      echo '#!/bin/sh
# zigup shell setup
# affix colons on either side of $PATH to simplify matching
case ":${PATH}:" in
    *:"'"$zig_root"'/bin":*)
        ;;
    *)
        export PATH='"$zig_root/"'bin:"$PATH"
        ;;
esac
case ":${PATH}:" in
    *:"'"$zig_root"'/zig":*)
        ;;
    *)
        export PATH='"$zig_root/"'zig:"$PATH"
        ;;
esac
' > "$zig_root/env"
      echo "add \`source $zig_root/env\` to your shell config"
    fi
    # shellcheck source=/dev/null
    source "$zig_root/env"

    zig_json_path="$zig_root/index.json"
    if [ ! -f "$zig_json_path" ]; then
      echo "initalizing index.json"
      curl -s https://ziglang.org/download/index.json > "$zig_json_path"
    fi
    json_ttl="600"
    seconds_since_fetch=$(($(date +%s) - $(date -r "$zig_json_path" +%s)))
    if [ "$json_ttl" -lt "$seconds_since_fetch" ]; then
      echo "fetching fresh index.json"
      curl -s https://ziglang.org/download/index.json >| "$zig_json_path"
    else
      echo "using cached index.json"
    fi

    zig_master_json="$(jq '.master' "$zig_json_path")"
    zig_master_version="$(jq -r '.version' <<< "$zig_master_json")"

    if command -v zig &> /dev/null; then
      installed_zig_version="$(zig version)"
    else
      installed_zig_version="no zig installed"
    fi

    if [[ $force == 0 && "$installed_zig_version" == "$zig_master_version" ]]; then
      echo "zig up to date"
    else
      echo "zig upgrade avaliable: $installed_zig_version -> $zig_master_version"
      if prompt_confirm "Proceed?"; then
        install_zig
      fi
    fi

   if prompt_confirm "build ZLS?"; then
     install_zls
   fi

}

main "$@"