feat: add preflight checks, rename ISO format, use Makefile targets in docs

- Add Arch Linux and disk space preflight checks to build.sh
- Rename ISO format: archangel-YYYY-MM-DD-vmlinuz-version-lts-x86_64.iso
- Update README to use Makefile targets throughout (make build, make clean)
- Note preflight checks in Prerequisites section

2 files changed, 27 insertions, 18 deletions

diff --git a/README.org b/README.org
index 5c7fd53..ccf273c 100644
--- a/README.org
+++ b/README.org
@@ -40,20 +40,23 @@ Archangel currently uses linux-lts for stability. Choosing linux and linux-zen k
 * Quick Start
 
 #+BEGIN_SRC bash
-# Build the ISO (requires root)
-sudo ./build.sh
+# Build the ISO (requires sudo)
+make build
 
 # Test in a VM
-./scripts/test-vm.sh
+make test-install
 
-# Or test with multiple disks for RAID
-./scripts/test-vm.sh --multi-disk
+# Or launch a VM manually for interactive testing
+./scripts/test-vm.sh
+./scripts/test-vm.sh --multi-disk   # multiple disks for RAID
 #+END_SRC
 
 Boot the ISO and run ~archangel~ to start the installation.
 
 * Prerequisites
 
+The build script will report if you're missing any of these in a preflight check.
+
 ** Build Host Requirements
 - Arch Linux (or Arch-based distribution)
 - Root/sudo access
@@ -71,7 +74,7 @@ Boot the ISO and run ~archangel~ to start the installation.
 ** Basic Build
 
 #+BEGIN_SRC bash
-sudo ./build.sh
+make build
 #+END_SRC
 
 The build script will:
@@ -84,15 +87,15 @@ The build script will:
 
 ** Build Output
 
-- ISO location: ~out/archangel-vmlinuz-{version}-lts-YYYY-MM-DD-x86_64.iso~
-- Example: ~archangel-vmlinuz-6.12.65-lts-2026-01-18-x86_64.iso~
+- ISO location: ~out/archangel-YYYY-MM-DD-vmlinuz-{version}-lts-x86_64.iso~
+- Example: ~archangel-2026-01-18-vmlinuz-6.12.65-lts-x86_64.iso~
 - Build logs: visible in terminal output (not saved to disk)
 
 ** Clean Rebuild
 
 #+BEGIN_SRC bash
-sudo rm -rf work out
-sudo ./build.sh
+make clean
+make build
 #+END_SRC
 
 * Project Structure
@@ -284,7 +287,7 @@ A complete example with all options is available at ~installer/archangel.conf.ex
 
 #+BEGIN_SRC bash
 # Write ISO to USB drive (replace /dev/sdX)
-sudo dd if=out/archangel-vmlinuz-*.iso of=/dev/sdX bs=4M status=progress oflag=sync
+sudo dd if=out/archangel-*.iso of=/dev/sdX bs=4M status=progress oflag=sync
 #+END_SRC
 
 ** Booting
@@ -397,8 +400,8 @@ operations only. Do not expose the live environment to untrusted networks.
 
 Clean the work directory and rebuild:
 #+BEGIN_SRC bash
-sudo rm -rf work
-sudo ./build.sh
+make clean
+make build
 #+END_SRC
 
 ** ZFS Module Not Loading
diff --git a/build.sh b/build.sh
index b94b731..a2e3ca3 100755
--- a/build.sh
+++ b/build.sh
@@ -74,10 +74,15 @@ cleanup_on_exit() {
 }
 trap cleanup_on_exit EXIT INT TERM
 
-# Check root
+# Preflight checks
 [[ $EUID -ne 0 ]] && error "This script must be run as root"
+[[ -f /etc/arch-release ]] || error "This script must be run on Arch Linux"
+
+MIN_FREE_GB=10
+free_kb=$(df --output=avail "$SCRIPT_DIR" | tail -1)
+free_gb=$((free_kb / 1024 / 1024))
+[[ $free_gb -lt $MIN_FREE_GB ]] && error "Insufficient disk space: ${free_gb}GB free, ${MIN_FREE_GB}GB required"
 
-# Check dependencies
 command -v mkarchiso >/dev/null 2>&1 || {
     info "Installing archiso..."
     pacman -Sy --noconfirm archiso
@@ -270,10 +275,11 @@ info "LTS Kernel version: $KERNEL_VER"
 
 # Update profiledef.sh with our ISO name
 info "Updating ISO metadata..."
-# Format: archangel-vmlinuz-6.12.65-lts-2026-01-18-x86_64.iso
+# Format: archangel-2026-01-18-vmlinuz-6.12.65-lts-x86_64.iso
+# mkarchiso builds: {iso_name}-{iso_version}-{arch}.iso
 ISO_DATE=$(date +%Y-%m-%d)
-sed -i "s/^iso_name=.*/iso_name=\"archangel-vmlinuz-${KERNEL_VER}-lts\"/" "$PROFILE_DIR/profiledef.sh"
-sed -i "s/^iso_version=.*/iso_version=\"${ISO_DATE}\"/" "$PROFILE_DIR/profiledef.sh"
+sed -i "s/^iso_name=.*/iso_name=\"archangel-${ISO_DATE}\"/" "$PROFILE_DIR/profiledef.sh"
+sed -i "s/^iso_version=.*/iso_version=\"vmlinuz-${KERNEL_VER}-lts\"/" "$PROFILE_DIR/profiledef.sh"
 # Fixed label for stable GRUB boot entry (default is date-based ARCH_YYYYMM)
 sed -i "s/^iso_label=.*/iso_label=\"ARCHANGEL\"/" "$PROFILE_DIR/profiledef.sh"