feat(setup): scripts/setup-telega.sh prepares the docker environment for telega

Verifies docker is installed and the daemon is reachable, then either pulls a public image (when `TELEGA_DOCKER_IMAGE` is set) or announces the in-Emacs build path (`M-x telega-server-build`) for the user to run once. Telegram auth (phone + verification code) is interactive on first `M-x telega` and not scripted here.

Same shape as setup-email.sh: helpers are sourceable for bats, `main` runs only under direct execution. 7 bats tests stub `docker` and `command` so the suite never talks to the real daemon.

1 files changed, 80 insertions, 0 deletions

diff --git a/scripts/setup-telega.sh b/scripts/setup-telega.sh
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+++ b/scripts/setup-telega.sh
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+#!/usr/bin/env bash
+# Craig Jennings <c@cjennings.net>
+#
+# Prepares the docker environment telega.el uses for TDLib.
+#
+# Sequence:
+# - Verifies docker is installed and the daemon is responsive.
+# - Verifies the user can talk to docker without sudo (group membership).
+# - Pulls the telega-server image if a public one is configured (env var
+#   `TELEGA_DOCKER_IMAGE'); otherwise prints the in-Emacs build command
+#   (`M-x telega-server-build') for the user to run once.
+#
+# Does NOT handle Telegram account auth -- phone number + verification
+# code is interactive and runs inside `M-x telega' on first launch.
+#
+# Sourceable: only `main' runs when the script is executed directly, so
+# the helpers can be tested with bats.
+
+set -euo pipefail
+
+# Public image override.  When set, the script pulls this image directly
+# instead of falling back to the in-Emacs build flow.  Default empty so
+# the script doesn't assume an image name that may or may not exist
+# upstream.
+: "${TELEGA_DOCKER_IMAGE:=}"
+
+ensure_docker_installed() {
+    if ! command -v docker >/dev/null 2>&1; then
+        echo "  ✗ docker not found on PATH"
+        echo "    install docker (https://docs.docker.com/get-docker/) and rerun"
+        return 1
+    fi
+    echo "  ✓ docker present: $(command -v docker)"
+}
+
+ensure_docker_running() {
+    if ! docker info >/dev/null 2>&1; then
+        echo "  ✗ cannot talk to the docker daemon"
+        echo "    start the daemon (e.g. 'sudo systemctl start docker') or"
+        echo "    add your user to the 'docker' group, then re-login and rerun"
+        return 1
+    fi
+    echo "  ✓ docker daemon reachable"
+}
+
+pull_or_announce_image() {
+    if [[ -z "$TELEGA_DOCKER_IMAGE" ]]; then
+        cat <<EOF
+  → no public image configured (set TELEGA_DOCKER_IMAGE to override)
+    build the telega-server image once from inside Emacs:
+      M-x telega-server-build
+    telega.el handles the docker build under the hood when
+    \`telega-use-docker' is t (set in modules/telega-config.el).
+EOF
+        return 0
+    fi
+    echo "  → pulling $TELEGA_DOCKER_IMAGE..."
+    if docker pull "$TELEGA_DOCKER_IMAGE"; then
+        echo "  ✓ pulled $TELEGA_DOCKER_IMAGE"
+    else
+        echo "  ✗ pull failed for $TELEGA_DOCKER_IMAGE"
+        return 1
+    fi
+}
+
+main() {
+    echo "→ checking docker..."
+    ensure_docker_installed
+    ensure_docker_running
+    echo "→ preparing telega-server image..."
+    pull_or_announce_image
+    echo "✅ Telega docker setup complete."
+    echo "   First launch: M-x telega -- enter phone + verification code interactively."
+}
+
+# Run main only when the script is executed directly.  Sourcing this file
+# (for example from a bats test) just defines the helpers above.
+if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
+    main "$@"
+fi