#!/usr/bin/env bash
# Descarga un artefacto del release fijado del motor (fenandosr/clusterlog)
# y verifica su checksum contra checksums.txt del mismo release. Nunca usa
# `latest`: la versión viene de .clusterlog-version.
set -euo pipefail

ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
ENGINE_REPO="${CLUSTERLOG_ENGINE_REPO:-fenandosr/clusterlog}"
VERSION="$(cat "$ROOT/.clusterlog-version")"
KIND="${1:?uso: fetch-engine.sh <bin|templates> <destino>}"
DEST="${2:?uso: fetch-engine.sh <bin|templates> <destino>}"

BASE_URL="https://github.com/${ENGINE_REPO}/releases/download/${VERSION}"
TMP="$(mktemp -d)"
trap 'rm -rf "$TMP"' EXIT

case "$KIND" in
  bin)
    os="$(uname -s | tr '[:upper:]' '[:lower:]')"
    arch="$(uname -m)"
    case "$arch" in x86_64) arch=amd64 ;; aarch64) arch=arm64 ;; esac
    asset="clusterlog_${os}_${arch}.tar.gz"
    ;;
  templates)
    asset="clusterlog-templates_${VERSION}.tar.gz"
    ;;
  *)
    echo "Tipo de artefacto desconocido: $KIND (use bin o templates)" >&2
    exit 1
    ;;
esac

echo "Descargando $asset (clusterlog $VERSION, $ENGINE_REPO)..."
curl -fsSL -o "$TMP/checksums.txt" "$BASE_URL/checksums.txt"
curl -fsSL -o "$TMP/$asset" "$BASE_URL/$asset"

expected="$(grep " $asset\$" "$TMP/checksums.txt" | awk '{print $1}')"
if [ -z "$expected" ]; then
  echo "ERROR: $asset no aparece en checksums.txt del release $VERSION" >&2
  exit 1
fi
computed="$(sha256sum "$TMP/$asset" | awk '{print $1}')"
if [ "$computed" != "$expected" ]; then
  echo "ERROR: checksum no coincide para $asset" >&2
  echo "  esperado: $expected" >&2
  echo "  obtenido: $computed" >&2
  exit 1
fi
echo "Checksum verificado."

case "$KIND" in
  bin)
    mkdir -p "$(dirname "$DEST")"
    tar xzf "$TMP/$asset" -C "$TMP" clusterlog
    install -m 0755 "$TMP/clusterlog" "$DEST"
    echo "Binario en $DEST ($("$DEST" version 2>/dev/null || true))"
    ;;
  templates)
    rm -rf "$DEST"
    mkdir -p "$DEST"
    tar xzf "$TMP/$asset" -C "$DEST"
    echo "Plantillas en $DEST"
    ;;
esac