# Tooling — config rendering, mod mirror, launcher fetch

## Summary

Three scripts in `./tooling/` turn the two env vars + templates into a working,
offline-capable stack. All are **cautious**: they halt on unset vars or missing
inputs rather than emit half-broken output.

## render-config.sh

Renders every `*.tmpl` into its real config by substituting `BASE_DOMAIN` /
`HOST_LAN_IP`. Caddy is excluded (it reads `{$BASE_DOMAIN}` natively).

Targets:
- `drasl/config/config.toml.tmpl`  → `drasl/config/config.toml`
- `dnsmasq/dnsmasq.conf.tmpl`       → `dnsmasq/dnsmasq.conf`

```bash
#!/usr/bin/env bash
set -euo pipefail
[ -f .env ] && set -a && . ./.env && set +a
: "${BASE_DOMAIN:?BASE_DOMAIN unset}"
: "${HOST_LAN_IP:?HOST_LAN_IP unset}"

render() {  # $1=tmpl  $2=out
  [ -f "$1" ] || { echo "missing template: $1"; exit 1; }
  envsubst '${BASE_DOMAIN} ${HOST_LAN_IP}' < "$1" > "$2"
  echo "rendered $2"
}

render drasl/config/config.toml.tmpl drasl/config/config.toml
render dnsmasq/dnsmasq.conf.tmpl      dnsmasq/dnsmasq.conf
```

> Note: `envsubst` with an explicit var list avoids clobbering `$`-syntax that
> belongs to the target file (e.g. dnsmasq/caddy literals).

## mirror-mods.sh

Vendors mod jars for offline install and rewrites packwiz URLs to the LAN host.
See `04-packwiz.md`. Outline:
1. For each `pack/mods/*.pw.toml`, read `[download] url` + `filename`.
2. Download jar → `pack/mods-files/` (served by Caddy under packwiz subdomain).
3. Rewrite `url` to `http://packwiz.${BASE_DOMAIN}/mods-files/<filename>`.
4. `packwiz refresh` to recompute hashes + `index.toml`.
Must halt if a download fails or a hash mismatches.

## mirror-assets.sh

Mirrors Minecraft asset objects for offline clients (the ~400 MB+ chunk) and lays
them out for Caddy + the Fjord "Assets Server" override. Full design in
`10-assets-mirror.md`. Verifies SHA1, idempotent, halts on mismatch.

## fetch-launcher.sh

Downloads all FjordLauncherUnlocked release assets → `mirror/launcher/<tag>/`.
Full script in `06-launcher.md`.

## Generated / gitignored

```
drasl/config/config.toml      # rendered
dnsmasq/dnsmasq.conf          # rendered
pack/mods-files/              # vendored jars
mirror/                       # launcher assets + mod mirror
.env                          # secrets + host-specific
```

## Tasks

- [ ] Write `tooling/render-config.sh` (above), `chmod +x`
- [ ] Write `tooling/mirror-mods.sh` (toml parse + download + rewrite + refresh)
- [ ] Write `tooling/mirror-assets.sh` (see 10)
- [ ] Write `tooling/fetch-launcher.sh` (see 06)
- [ ] Add `gettext` (envsubst) + `jq` to host prereqs doc
- [ ] Update `.gitignore` for rendered configs + `mirror/` + `pack/mods-files/`
- [ ] `build-stack.sh` orchestrator (preflight + `--prep` online + `--up` offline) — DONE, sequences the sub-scripts; see plan/12