#!/bin/sh
# Installs the difinity command line:  curl -fsSL https://get.difinity.ai | sh
# It needs Node 20 or newer. It puts the program in ~/.difinity/app and a `difinity`
# command in ~/.local/bin. It does not sign you in or change Claude Code or Codex;
# run `difinity setup` for that.
#
# Settings (all optional):
#   DIFINITY_DOWNLOAD_URL  where difinity.tgz and difinity.tgz.sha256 are served
#   DIFINITY_HOME          install under here instead of ~/.difinity
#   DIFINITY_BIN_DIR       put the command here instead of ~/.local/bin
#   DIFINITY_NO_MODIFY_PATH=1  do not add the command's folder to your shell profile
set -eu

BASE="${DIFINITY_DOWNLOAD_URL:-https://get.difinity.ai}"
HOME_DIR="${DIFINITY_HOME:-$HOME/.difinity}"
APP="$HOME_DIR/app"
BIN_DIR="${DIFINITY_BIN_DIR:-$HOME/.local/bin}"

say() { printf '%s\n' "$*"; }
fail() { printf 'Install stopped: %s\n' "$*" >&2; exit 1; }

command -v node >/dev/null 2>&1 || fail "Node.js 20 or newer is needed and was not found. Install it from https://nodejs.org, then run this again."
MAJOR=$(node -p 'process.versions.node.split(".")[0]')
[ "$MAJOR" -ge 20 ] || fail "Node.js $MAJOR is too old. Version 20 or newer is needed."
command -v curl >/dev/null 2>&1 || fail "curl is needed and was not found."
command -v tar >/dev/null 2>&1 || fail "tar is needed and was not found."

TMP=$(mktemp -d)
trap 'rm -rf "$TMP"' EXIT INT TERM

say "Installing Difinity ..."
curl -fsSL "$BASE/difinity.tgz" -o "$TMP/difinity.tgz" || fail "could not download $BASE/difinity.tgz"
curl -fsSL "$BASE/difinity.tgz.sha256" -o "$TMP/difinity.tgz.sha256" || fail "could not download the checksum"

WANT=$(awk '{print $1}' "$TMP/difinity.tgz.sha256")
if command -v shasum >/dev/null 2>&1; then GOT=$(shasum -a 256 "$TMP/difinity.tgz" | awk '{print $1}')
elif command -v sha256sum >/dev/null 2>&1; then GOT=$(sha256sum "$TMP/difinity.tgz" | awk '{print $1}')
else fail "shasum or sha256sum is needed to check the download."; fi
[ "$WANT" = "$GOT" ] || fail "the download did not match its checksum. Nothing was installed."

mkdir -p "$TMP/app" "$HOME_DIR" "$BIN_DIR"
tar -xzf "$TMP/difinity.tgz" -C "$TMP/app"
[ -f "$TMP/app/bin/difinity.mjs" ] || fail "the download is not a Difinity release."

# Swap the new copy in. The old one stays until the new one is in place.
rm -rf "$APP.old"
[ -d "$APP" ] && mv "$APP" "$APP.old"
mv "$TMP/app" "$APP"
rm -rf "$APP.old"

LAUNCHER="$BIN_DIR/difinity"
printf '#!/bin/sh\nexec node "%s/bin/difinity.mjs" "$@"\n' "$APP" > "$LAUNCHER"
chmod 755 "$LAUNCHER"

say "Installed Difinity $("$LAUNCHER" version) to $APP"

case ":$PATH:" in
  *":$BIN_DIR:"*) ;;
  *)
    LINE="export PATH=\"$BIN_DIR:\$PATH\""
    PROFILE=""
    case "${SHELL:-}" in
      */zsh) PROFILE="$HOME/.zshrc" ;;
      */bash) if [ -f "$HOME/.bash_profile" ]; then PROFILE="$HOME/.bash_profile"; else PROFILE="$HOME/.bashrc"; fi ;;
    esac
    if [ -n "$PROFILE" ] && [ "${DIFINITY_NO_MODIFY_PATH:-}" != "1" ]; then
      if ! grep -qF "$BIN_DIR" "$PROFILE" 2>/dev/null; then printf '\n# Added by the Difinity installer\n%s\n' "$LINE" >> "$PROFILE"; fi
      say "Added $BIN_DIR to your PATH in $PROFILE. Open a new terminal, or run:"
    else
      say "Add Difinity to your PATH by running:"
    fi
    say "  $LINE"
    ;;
esac

say ""
say "Next, run:  difinity setup"