#!/bin/sh
# Install the windpaint CLI from the GitHub releases of windpaint-ai/cli.
#
#   curl -fsSL https://get.windpaint.ai | sh
#   curl -fsSL https://get.windpaint.ai | WINDPAINT_VERSION=0.1.0 sh
#
# Env:
#   WINDPAINT_VERSION      version to install, e.g. 0.1.0 (default: latest release)
#   WINDPAINT_INSTALL_DIR  target directory (default: /usr/local/bin if writable, else ~/.local/bin)
set -eu

REPO="windpaint-ai/cli"
BIN="windpaint"

err() { echo "install: $*" >&2; exit 1; }
need() { command -v "$1" >/dev/null 2>&1 || err "$1 is required"; }

need uname
need tar
if command -v curl >/dev/null 2>&1; then
  fetch() { curl -fsSL "$1" -o "$2"; }
  fetch_stdout() { curl -fsSL "$1"; }
  final_url() { curl -fsSLI -o /dev/null -w '%{url_effective}' "$1"; }
elif command -v wget >/dev/null 2>&1; then
  fetch() { wget -qO "$2" "$1"; }
  fetch_stdout() { wget -qO- "$1"; }
  final_url() { wget -S --spider "$1" 2>&1 | sed -n 's/^ *[Ll]ocation: *\([^ ]*\).*/\1/p' | tail -n1 | tr -d '\r'; }
else
  err "curl or wget is required"
fi

os=$(uname -s | tr '[:upper:]' '[:lower:]')
case "$os" in
  linux|darwin) ;;
  *) err "unsupported OS $os (on Windows, download the .zip from https://github.com/$REPO/releases)" ;;
esac

arch=$(uname -m)
case "$arch" in
  x86_64|amd64) arch=amd64 ;;
  arm64|aarch64) arch=arm64 ;;
  *) err "unsupported architecture $arch" ;;
esac

version="${WINDPAINT_VERSION:-}"
if [ -z "$version" ]; then
  # The releases/latest redirect is not rate limited like the API.
  latest=$(final_url "https://github.com/$REPO/releases/latest" 2>/dev/null || true)
  case "$latest" in
    */releases/tag/*) version="${latest##*/tag/}" ;;
  esac
  if [ -z "$version" ]; then
    version=$(fetch_stdout "https://api.github.com/repos/$REPO/releases/latest" \
      | sed -n 's/.*"tag_name": *"v\{0,1\}\([^"]*\)".*/\1/p' | head -n1)
  fi
  [ -n "$version" ] || err "could not determine the latest version; set WINDPAINT_VERSION"
fi
version="${version#v}"

archive="${BIN}_${version}_${os}_${arch}.tar.gz"
base="https://github.com/$REPO/releases/download/v$version"

tmp=$(mktemp -d)
trap 'rm -rf "$tmp"' EXIT
trap 'exit 130' INT TERM

echo "Downloading $BIN $version ($os/$arch)..." >&2
fetch "$base/$archive" "$tmp/$archive" || err "download failed: $base/$archive"
fetch "$base/checksums.txt" "$tmp/checksums.txt" || err "download failed: $base/checksums.txt"

expected=$(grep " $archive\$" "$tmp/checksums.txt" | cut -d' ' -f1)
[ -n "$expected" ] || err "$archive is not listed in checksums.txt"
if command -v sha256sum >/dev/null 2>&1; then
  actual=$(sha256sum "$tmp/$archive" | cut -d' ' -f1)
elif command -v shasum >/dev/null 2>&1; then
  actual=$(shasum -a 256 "$tmp/$archive" | cut -d' ' -f1)
else
  err "sha256sum or shasum is required to verify the download"
fi
[ "$expected" = "$actual" ] || err "checksum mismatch for $archive"

tar -xzf "$tmp/$archive" -C "$tmp" "$BIN"

dir="${WINDPAINT_INSTALL_DIR:-}"
if [ -z "$dir" ]; then
  if [ -w /usr/local/bin ]; then dir=/usr/local/bin; else dir="$HOME/.local/bin"; fi
fi
mkdir -p "$dir"
install -m 0755 "$tmp/$BIN" "$dir/$BIN" 2>/dev/null || { cp "$tmp/$BIN" "$dir/$BIN" && chmod 0755 "$dir/$BIN"; }

echo "Installed $dir/$BIN" >&2
case ":$PATH:" in
  *":$dir:"*) ;;
  *)
    if [ "$dir" = "$HOME/.local/bin" ]; then
      echo "Add it to your PATH to run $BIN:  export PATH=\"\$HOME/.local/bin:\$PATH\"" >&2
    else
      echo "Add it to your PATH to run $BIN:  export PATH=\"$dir:\$PATH\"" >&2
    fi
    ;;
esac
"$dir/$BIN" version --format text >&2 || true