#!/usr/bin/env bash
# PrepCode installer for macOS and Linux.
# Usage:  curl -fsSL https://prepcode.dev/install.sh | bash
#
# macOS:  downloads the latest .dmg, copies PrepCode into Applications,
#         removes the "downloaded from the internet" flag (the app is not
#         signed yet) and opens it.
# Linux:  downloads the latest .deb (Debian, Ubuntu), .rpm (Fedora, openSUSE)
#         or AppImage (everything else), installs it and opens it.
set -euo pipefail

REPO="dharanish01g/prepcode"

say()  { printf '\033[1m==>\033[0m %s\n' "$1"; }
fail() { printf '\033[31mError:\033[0m %s\n' "$1" >&2; exit 1; }
have() { command -v "$1" >/dev/null 2>&1; }

OS="$(uname -s)"
case "$OS" in
  Darwin|Linux) ;;
  *) fail "This installer is for macOS and Linux. Get other downloads at https://prepcode.dev/download/" ;;
esac

case "$(uname -m)" in
  arm64|aarch64) ARCH_RE="aarch64|arm64"; ARCH="arm64" ;;
  x86_64|amd64)  ARCH_RE="x64|x86_64|amd64"; ARCH="x64" ;;
  *) fail "Unsupported processor: $(uname -m)" ;;
esac

have curl || fail "curl is required."

TMP="$(mktemp -d)"
MNT="$TMP/mount"
cleanup() {
  [ "$OS" = "Darwin" ] && hdiutil detach "$MNT" -quiet -force >/dev/null 2>&1 || true
  rm -rf "$TMP"
}
trap cleanup EXIT

# List the download links of the latest release (one per line)
list_assets() {
  local urls tag
  urls="$(curl -fsSL "https://api.github.com/repos/$REPO/releases/latest" 2>/dev/null \
    | grep -o '"browser_download_url": *"[^"]*"' | grep -o 'https://[^"]*' || true)"
  if [ -z "$urls" ]; then
    # The GitHub API can be rate limited on shared networks. Use the release page instead.
    tag="$(curl -fsSLI -o /dev/null -w '%{url_effective}' "https://github.com/$REPO/releases/latest" | sed 's#.*/tag/##')"
    [ -n "$tag" ] || return 0
    urls="$(curl -fsSL "https://github.com/$REPO/releases/expanded_assets/$tag" 2>/dev/null \
      | grep -o 'href="[^"]*/releases/download/[^"]*"' | sed 's#href="#https://github.com#; s#"$##' || true)"
  fi
  printf '%s\n' "$urls"
}

# pick <extension-regex> [arch-regex]: first matching link
pick() {
  if [ -n "${2:-}" ]; then
    printf '%s\n' "$ASSETS" | grep -E "(${2})[^/]*\.(${1})\$" | head -n 1 || true
  else
    printf '%s\n' "$ASSETS" | grep -E "\.(${1})\$" | head -n 1 || true
  fi
}

download() {
  say "Downloading ${1##*/}..."
  curl -fL --progress-bar -o "$2" "$1" || fail "Download failed. Check your internet connection and try again."
}

say "Finding the latest PrepCode..."
ASSETS="$(list_assets)"
[ -n "$ASSETS" ] || fail "Could not find the latest release. Try again, or download from https://prepcode.dev/download/"

# ---------------- macOS ----------------
if [ "$OS" = "Darwin" ]; then
  APP="prepcode.app"
  URL="$(pick 'dmg' 'aarch64|arm64')"
  [ "$ARCH" = "x64" ] && URL="$(pick 'dmg' 'x64|x86_64')"
  [ -n "$URL" ] || fail "No macOS download found for this Mac."
  download "$URL" "$TMP/prepcode.dmg"

  say "Installing..."
  mkdir -p "$MNT"
  hdiutil attach "$TMP/prepcode.dmg" -nobrowse -quiet -mountpoint "$MNT" || fail "Could not open the downloaded file."
  SRC="$(find "$MNT" -maxdepth 1 -name '*.app' | head -n 1)"
  [ -n "$SRC" ] || fail "PrepCode was not found inside the download."
  DEST="/Applications"
  if [ ! -w "$DEST" ]; then DEST="$HOME/Applications"; mkdir -p "$DEST"; fi
  rm -rf "$DEST/$APP"
  ditto "$SRC" "$DEST/$APP"
  hdiutil detach "$MNT" -quiet >/dev/null 2>&1 || true

  say "Removing the macOS download warning..."
  xattr -cr "$DEST/$APP"

  say "Opening PrepCode..."
  open "$DEST/$APP"
  printf '\nDone. PrepCode is in %s and will start normally from now on.\n' "$DEST"
  exit 0
fi

# ---------------- Linux ----------------
SUDO=""
if [ "$(id -u)" -ne 0 ]; then have sudo && SUDO="sudo"; fi
INSTALLED=""

if have apt-get && have dpkg && { [ -z "$SUDO" ] && [ "$(id -u)" -eq 0 ] || [ -n "$SUDO" ]; }; then
  URL="$(pick 'deb' "$ARCH_RE")"
  if [ -n "$URL" ]; then
    download "$URL" "$TMP/prepcode.deb"
    say "Installing (you may be asked for your password)..."
    $SUDO apt-get install -y "$TMP/prepcode.deb" && INSTALLED="deb"
  fi
elif have rpm && { have dnf || have zypper || have yum; } && { [ "$(id -u)" -eq 0 ] || [ -n "$SUDO" ]; }; then
  URL="$(pick 'rpm' "$ARCH_RE")"
  if [ -n "$URL" ]; then
    download "$URL" "$TMP/prepcode.rpm"
    say "Installing (you may be asked for your password)..."
    if have dnf; then $SUDO dnf install -y "$TMP/prepcode.rpm" && INSTALLED="rpm"
    elif have zypper; then $SUDO zypper --non-interactive --no-gpg-checks install "$TMP/prepcode.rpm" && INSTALLED="rpm"
    else $SUDO yum install -y "$TMP/prepcode.rpm" && INSTALLED="rpm"; fi
  fi
fi

if [ -z "$INSTALLED" ]; then
  # AppImage: no admin rights needed
  URL="$(pick 'AppImage' "$ARCH_RE")"
  [ -n "$URL" ] || fail "No Linux download found for this computer."
  DIR="$HOME/.local/share/prepcode"
  mkdir -p "$DIR" "$HOME/.local/bin" "$HOME/.local/share/applications"
  download "$URL" "$DIR/prepcode.AppImage"
  chmod +x "$DIR/prepcode.AppImage"
  ln -sf "$DIR/prepcode.AppImage" "$HOME/.local/bin/prepcode"
  cat > "$HOME/.local/share/applications/prepcode.desktop" <<DESK
[Desktop Entry]
Type=Application
Name=PrepCode
Comment=Code editor for students
Exec=$DIR/prepcode.AppImage
Terminal=false
Categories=Development;IDE;
DESK
  INSTALLED="appimage"
  have fusermount || printf 'Note: if PrepCode does not open, install FUSE 2 (for example: sudo apt install libfuse2).\n'
fi

if [ -n "${DISPLAY:-}${WAYLAND_DISPLAY:-}" ]; then
  say "Opening PrepCode..."
  if [ "$INSTALLED" = "appimage" ]; then LAUNCH="$HOME/.local/share/prepcode/prepcode.AppImage"; else LAUNCH="$(command -v prepcode || echo prepcode)"; fi
  nohup "$LAUNCH" >/dev/null 2>&1 &
fi
printf '\nDone. Find PrepCode in your applications menu, or run: prepcode\n'