#!/bin/sh
set -e

# Compute Portal CLI installer
# Usage: curl -fsSL https://install.computeportal.io | sh
#
# Environment variables:
#   CP_INSTALL_DIR   Install directory (default: /usr/local/bin, fallback: ~/.local/bin)
#   CP_VERSION       Pin a specific version (default: latest)
#
# Flags (via sh -s --):
#   --install-dir <dir>   Install directory
#   --version <ver>       Pin a specific version

BASE_URL="${CP_BASE_URL:-https://install.computeportal.io}"
BINARY_NAME="cpctl"

# ── Parse flags ───────────────────────────────────────────────────────────────
while [ $# -gt 0 ]; do
    case "$1" in
        --install-dir) CP_INSTALL_DIR="$2"; shift 2 ;;
        --version)     CP_VERSION="$2";     shift 2 ;;
        *) printf 'Unknown flag: %s\nUsage: curl -fsSL %s | sh -s -- [--install-dir DIR] [--version VER]\n' "$1" "${BASE_URL}" >&2; exit 1 ;;
    esac
done

# ── Resolve install directory ─────────────────────────────────────────────────
if [ -n "${CP_INSTALL_DIR:-}" ]; then
    INSTALL_DIR="${CP_INSTALL_DIR}"
elif [ -w "/usr/local/bin" ]; then
    INSTALL_DIR="/usr/local/bin"
else
    INSTALL_DIR="${HOME}/.local/bin"
fi

# ── Terminal colours ──────────────────────────────────────────────────────────
if [ -t 1 ] && command -v tput >/dev/null 2>&1; then
    BOLD="$(tput bold 2>/dev/null || true)"
    GREEN="$(tput setaf 2 2>/dev/null || true)"
    YELLOW="$(tput setaf 3 2>/dev/null || true)"
    RED="$(tput setaf 1 2>/dev/null || true)"
    RESET="$(tput sgr0 2>/dev/null || true)"
else
    BOLD="" GREEN="" YELLOW="" RED="" RESET=""
fi

log()  { printf '%s==>%s %s\n' "${GREEN}${BOLD}" "${RESET}" "$*"; }
warn() { printf '%s==>%s %sWARNING:%s %s\n' "${YELLOW}${BOLD}" "${RESET}" "${YELLOW}" "${RESET}" "$*"; }
die()  { printf '%s==>%s %sERROR:%s %s\n' "${RED}${BOLD}" "${RESET}" "${RED}" "${RESET}" "$*" >&2; exit 1; }

# ── Detect OS ─────────────────────────────────────────────────────────────────
OS="$(uname -s 2>/dev/null | tr '[:upper:]' '[:lower:]')"
case "${OS}" in
    linux)  OS="linux" ;;
    darwin) OS="darwin" ;;
    *)      die "Unsupported OS: ${OS}. Supported: linux, darwin." ;;
esac

# ── Detect architecture ───────────────────────────────────────────────────────
ARCH="$(uname -m 2>/dev/null)"
case "${ARCH}" in
    x86_64|amd64)        ARCH="amd64" ;;
    aarch64|arm64|arm*)  ARCH="arm64" ;;
    *)                   die "Unsupported architecture: ${ARCH}. Supported: amd64, arm64." ;;
esac

# ── Detect download tool ──────────────────────────────────────────────────────
if command -v curl >/dev/null 2>&1; then
    DOWNLOAD="curl -fsSL"
    DOWNLOAD_TO="curl -fsSL -o"
elif command -v wget >/dev/null 2>&1; then
    DOWNLOAD="wget -qO-"
    DOWNLOAD_TO="wget -qO"
else
    die "curl or wget is required to install the Compute Portal CLI."
fi

# ── Resolve version ───────────────────────────────────────────────────────────
if [ -n "${CP_VERSION:-}" ]; then
    VERSION="${CP_VERSION}"
else
    log "Fetching latest version..."
    VERSION="$(${DOWNLOAD} "${BASE_URL}/version" 2>/dev/null | tr -d '[:space:]')"
    [ -n "${VERSION}" ] || die "Could not fetch version from ${BASE_URL}/version"
fi

log "Installing Compute Portal CLI ${VERSION} (${OS}/${ARCH})..."

# ── Build URLs ────────────────────────────────────────────────────────────────
BINARY_ASSET="cpctl-${OS}-${ARCH}"
DOWNLOAD_URL="${BASE_URL}/releases/${VERSION}/${BINARY_ASSET}"
CHECKSUM_URL="${BASE_URL}/releases/${VERSION}/${BINARY_ASSET}.sha256"

# ── Ensure install dir exists and is writable ─────────────────────────────────
mkdir -p "${INSTALL_DIR}" 2>/dev/null || die "Cannot create install directory: ${INSTALL_DIR}"
[ -w "${INSTALL_DIR}" ] || die "Install directory is not writable: ${INSTALL_DIR}. Set CP_INSTALL_DIR to a writable path or use --install-dir."

BINARY_PATH="${INSTALL_DIR}/${BINARY_NAME}"

if [ "${INSTALL_DIR}" = "${HOME}/.local/bin" ] && [ -z "${CP_INSTALL_DIR:-}" ]; then
    warn "/usr/local/bin is not writable — installing to ${INSTALL_DIR} instead."
    warn "Add this to your shell profile: export PATH=\"${INSTALL_DIR}:\$PATH\""
fi

# ── Download binary ───────────────────────────────────────────────────────────
TMP_FILE="$(mktemp)"
trap 'rm -f "${TMP_FILE}"' EXIT INT TERM

log "Downloading ${DOWNLOAD_URL}..."
${DOWNLOAD_TO} "${TMP_FILE}" "${DOWNLOAD_URL}" || die "Download failed. Try: CP_VERSION=<version> curl -fsSL ${BASE_URL} | sh"

# ── Verify checksum ───────────────────────────────────────────────────────────
EXPECTED="$(${DOWNLOAD} "${CHECKSUM_URL}" 2>/dev/null | awk '{print $1}' || true)"
if [ -n "${EXPECTED}" ]; then
    log "Verifying checksum..."
    if command -v sha256sum >/dev/null 2>&1; then
        ACTUAL="$(sha256sum "${TMP_FILE}" | awk '{print $1}')"
    elif command -v shasum >/dev/null 2>&1; then
        ACTUAL="$(shasum -a 256 "${TMP_FILE}" | awk '{print $1}')"
    else
        warn "sha256sum/shasum not found — skipping checksum verification."
        ACTUAL="${EXPECTED}"
    fi
    [ "${ACTUAL}" = "${EXPECTED}" ] || die "Checksum mismatch. The download may be corrupt."
else
    warn "Checksum not available — skipping verification."
fi

# ── Install ───────────────────────────────────────────────────────────────────
chmod +x "${TMP_FILE}"
log "Installing to ${BINARY_PATH}..."
mv "${TMP_FILE}" "${BINARY_PATH}"

# ── Verify ────────────────────────────────────────────────────────────────────
if ! command -v "${BINARY_NAME}" >/dev/null 2>&1; then
    warn "${INSTALL_DIR} may not be in your PATH."
    warn "Add this to your shell profile: export PATH=\"${INSTALL_DIR}:\$PATH\""
fi

INSTALLED_VERSION="$("${BINARY_PATH}" version 2>/dev/null || echo "unknown")"

printf '\n'
printf '%s✓%s Compute Portal CLI installed successfully!\n' "${GREEN}${BOLD}" "${RESET}"
printf '  Version : %s\n' "${INSTALLED_VERSION}"
printf '  Binary  : %s\n' "${BINARY_PATH}"
printf '\n'
printf 'Get started:\n'
printf '  %scpctl login --token <your-api-token>%s\n' "${BOLD}" "${RESET}"
printf '  %scpctl deploy --image nginx:latest%s\n' "${BOLD}" "${RESET}"
printf '\n'
printf 'Get your API token at: %shttps://computeportal.io/user/orders%s\n' "${BOLD}" "${RESET}"
printf 'Documentation:         %shttps://docs.computeportal.io%s\n' "${BOLD}" "${RESET}"