#!/bin/sh
# Impeccable launcher. Runs the platform binary shipped next to this script:
#   <this dir>/bin/<os>-<arch>/impeccable
# Order: $IMPECCABLE_BIN, the sibling binary, ~/.impeccable/bin/impeccable,
# then `impeccable` on PATH (the npm shim). Never needs Node.
set -eu

if [ -n "${IMPECCABLE_BIN:-}" ] && [ -x "${IMPECCABLE_BIN}" ]; then
  exec "${IMPECCABLE_BIN}" "$@"
fi

dir=$(CDPATH= cd -- "$(dirname -- "$0")" && pwd)

# What the binary needs to know about its home: the skill directory (for
# reference/*.md and command-metadata.json) and how to name itself in the
# commands it prints.
: "${IMPECCABLE_SKILL_DIR:=$(CDPATH= cd -- "$dir/.." && pwd)}"
: "${IMPECCABLE_SELF:=$0}"
export IMPECCABLE_SKILL_DIR IMPECCABLE_SELF

case "$(uname -s 2>/dev/null || echo unknown)" in
  Darwin) os=darwin ;;
  Linux) os=linux ;;
  MINGW*|MSYS*|CYGWIN*|Windows_NT) os=windows ;;
  *) os=unknown ;;
esac
case "$(uname -m 2>/dev/null || echo unknown)" in
  arm64|aarch64) arch=arm64 ;;
  x86_64|amd64) arch=x64 ;;
  *) arch=unknown ;;
esac

bin="$dir/bin/$os-$arch/impeccable"
[ "$os" = windows ] && bin="$bin.exe"

if [ -x "$bin" ]; then
  exec "$bin" "$@"
fi
if [ -f "$bin" ]; then
  # Lost the executable bit in transit (zip extraction, some copiers).
  chmod +x "$bin" 2>/dev/null && exec "$bin" "$@"
fi
if [ -x "${HOME:-/nonexistent}/.impeccable/bin/impeccable" ]; then
  exec "${HOME}/.impeccable/bin/impeccable" "$@"
fi
# Version-pinned user cache, filled by the download below or by `impeccable update`.
version=""
[ -f "$dir/VERSION" ] && version=$(tr -d '[:space:]' < "$dir/VERSION")
cache_root="${IMPECCABLE_HOME:-${HOME:-/nonexistent}/.impeccable}"
cached="$cache_root/bin/$version/impeccable"
if [ -n "$version" ] && [ -x "$cached" ]; then
  exec "$cached" "$@"
fi
if command -v impeccable >/dev/null 2>&1; then
  exec impeccable "$@"
fi

# Last resort: fetch this version's binary for the current platform from the
# public release channel into the user cache. Needs network; sandboxes without
# egress preinstall the binary on PATH instead.
if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
  base="${IMPECCABLE_DOWNLOAD_BASE:-https://github.com/renaissance-geek-inc/impeccable-dist/releases/download}"
  asset="impeccable-$os-$arch"
  [ "$os" = windows ] && asset="$asset.exe"
  url="$base/v$version/$asset"
  tmp="$cache_root/bin/$version/.impeccable.part.$$"
  mkdir -p "$cache_root/bin/$version" 2>/dev/null
  fetched=0
  if command -v curl >/dev/null 2>&1; then
    curl -fsSL --retry 2 -o "$tmp" "$url" 2>/dev/null && fetched=1
  elif command -v wget >/dev/null 2>&1; then
    wget -q -O "$tmp" "$url" 2>/dev/null && fetched=1
  fi
  if [ "$fetched" = 1 ]; then
    if command -v curl >/dev/null 2>&1 && curl -fsSL -o "$tmp.sha256" "$url.sha256" 2>/dev/null; then
      expected=$(cut -d' ' -f1 < "$tmp.sha256")
      actual=""
      if command -v shasum >/dev/null 2>&1; then actual=$(shasum -a 256 "$tmp" | cut -d' ' -f1)
      elif command -v sha256sum >/dev/null 2>&1; then actual=$(sha256sum "$tmp" | cut -d' ' -f1); fi
      if [ -n "$actual" ] && [ "$actual" != "$expected" ]; then
        rm -f "$tmp" "$tmp.sha256"
        echo "impeccable: checksum mismatch downloading $url" >&2
        exit 127
      fi
      rm -f "$tmp.sha256"
    fi
    chmod +x "$tmp" 2>/dev/null
    mv -f "$tmp" "$cached" && exec "$cached" "$@"
  fi
  rm -f "$tmp" 2>/dev/null
fi

echo "impeccable: no binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2
echo "Install one: npm i -g impeccable, or download impeccable-$os-$arch from https://github.com/renaissance-geek-inc/impeccable-dist/releases into $cache_root/bin/$version/impeccable" >&2
exit 127