#!/usr/bin/env bash
# docker-entrypoint.sh — custom-gitea-runner bootstrap and daemon startup
# Runs as PID 1 via tini. Handles validation, optional CA trust, registration, and daemon start.
set -euo pipefail

RUNNER_CONFIG_PATH="${RUNNER_CONFIG_PATH:-/config/runner.yaml}"
RUNNER_WORKDIR="${RUNNER_WORKDIR:-/work}"

# ─── Banner ───────────────────────────────────────────────────────────────────

print_banner() {
    echo "======================================================"
    echo "  custom-gitea-runner"
    echo "  Image version : ${IMAGE_VERSION:-unknown}"
    echo "  Git revision  : ${GIT_REVISION:-unknown}"
    echo "======================================================"
    echo "Runtime:"
    echo "  act_runner : $(act_runner --version 2>&1 | head -1 || echo 'unknown')"
    echo "  node       : $(node --version 2>&1 || echo 'unknown')"
    echo "  npm        : $(npm --version 2>&1 || echo 'unknown')"
    echo "  git        : $(git --version 2>&1 | awk '{print $3}' || echo 'unknown')"
    echo "  docker     : $(docker --version 2>&1 | awk '{print $3}' | tr -d ',' || echo 'unavailable')"
    echo "Config:"
    echo "  Config path  : ${RUNNER_CONFIG_PATH}"
    echo "  Work dir     : ${RUNNER_WORKDIR}"
    echo "  Gitea URL    : ${GITEA_INSTANCE_URL:-[not set]}"
    echo "  Runner name  : ${GITEA_RUNNER_NAME:-[not set]}"
    echo "  Labels       : ${GITEA_RUNNER_LABELS:-[not set]}"
    echo "======================================================"
}

# ─── Binary validation ────────────────────────────────────────────────────────

validate_binaries() {
    local missing=0
    for bin in act_runner git node npm; do
        if ! command -v "$bin" &>/dev/null; then
            echo "[ERROR] Required binary not found: ${bin}"
            missing=1
        fi
    done
    if [ "$missing" -ne 0 ]; then
        echo "[FATAL] Missing required binaries. This is an image build issue."
        exit 1
    fi
    echo "[OK] All required binaries present."
}

# ─── Custom CA trust (optional) ───────────────────────────────────────────────

install_custom_ca() {
    local ca_dir="/config/trusted-ca"
    if [ -d "$ca_dir" ] && compgen -G "${ca_dir}/*.crt" >/dev/null 2>&1; then
        echo "[CA] Installing custom CA certificates from ${ca_dir} ..."
        cp "${ca_dir}"/*.crt /usr/local/share/ca-certificates/ 2>/dev/null || true
        update-ca-certificates --fresh 2>&1 | grep -v "^$" || true
        echo "[CA] Custom CA trust updated."
    fi
}

# ─── Registration (Mode B: bootstrap from env vars) ───────────────────────────

require_env() {
    local var="$1"
    if [ -z "${!var:-}" ]; then
        echo "[FATAL] Required environment variable not set: ${var}"
        exit 1
    fi
}

# Rewrite the `labels:` list in the runner config. act_runner reads labels
# from the config file at registration time and IGNORES the `register --labels`
# flag whenever the config already exists — so to honor GITEA_RUNNER_LABELS we
# must edit the generated config before registering.
apply_labels() {
    local labels_csv="$1" config="$2" tmp
    echo "[BOOTSTRAP] Applying labels: ${labels_csv}"
    tmp="$(mktemp)"
    awk -v csv="${labels_csv}" '
        BEGIN { n = split(csv, arr, ",") }
        /^[[:space:]]+labels:[[:space:]]*$/ {
            print
            for (i = 1; i <= n; i++) {
                gsub(/^[ \t]+|[ \t]+$/, "", arr[i])
                printf "    - \"%s\"\n", arr[i]
            }
            inlabels = 1
            next
        }
        inlabels == 1 {
            if ($0 ~ /^[[:space:]]+-[[:space:]]/) { next }
            inlabels = 0
        }
        { print }
    ' "${config}" > "${tmp}" && mv "${tmp}" "${config}"
}

register_runner() {
    echo "[BOOTSTRAP] No config found at ${RUNNER_CONFIG_PATH}. Initiating registration."

    require_env GITEA_INSTANCE_URL
    require_env GITEA_RUNNER_TOKEN
    require_env GITEA_RUNNER_NAME

    mkdir -p "$(dirname "${RUNNER_CONFIG_PATH}")"

    # Generate the default config template (includes cache/container defaults),
    # then inject the operator's labels into it before registering.
    act_runner generate-config > "${RUNNER_CONFIG_PATH}"

    local labels="${GITEA_RUNNER_LABELS:-ubuntu-latest:docker://node:20-bullseye}"
    apply_labels "${labels}" "${RUNNER_CONFIG_PATH}"

    act_runner register \
        --config "${RUNNER_CONFIG_PATH}" \
        --instance "${GITEA_INSTANCE_URL}" \
        --token "${GITEA_RUNNER_TOKEN}" \
        --name "${GITEA_RUNNER_NAME}" \
        --no-interactive

    echo "[BOOTSTRAP] Registration complete. Config at ${RUNNER_CONFIG_PATH}."
}

# ─── Main ─────────────────────────────────────────────────────────────────────

print_banner
validate_binaries
install_custom_ca

mkdir -p "${RUNNER_WORKDIR}"

if [ ! -f "${RUNNER_CONFIG_PATH}" ]; then
    register_runner
else
    echo "[INFO] Existing config found at ${RUNNER_CONFIG_PATH}. Skipping registration."
fi

echo "[START] Starting act_runner daemon ..."
exec act_runner daemon --config "${RUNNER_CONFIG_PATH}"