#!/usr/bin/env bash
# =============================================================================
# kamos-build.sh
#
# Build the KAMOS Gaming OS image directly on this Mac, push to Forgejo,
# and sign it. Replaces the broken Forgejo CI workflow.
#
# Usage:
#   chmod +x kamos-build.sh
#   ./kamos-build.sh
#
# What it does:
#   1. Checks Podman + cosign are installed (offers to install if not)
#   2. Starts the Podman virtual machine (Linux env on macOS)
#   3. Builds linux/amd64 image (uses QEMU emulation on Apple Silicon - slow
#      first time, ~30-60 min; faster afterwards because layers cache)
#   4. Logs into your Forgejo registry
#   5. Pushes the image
#   6. Signs it with cosign
# =============================================================================

set -euo pipefail

# ---- config ----------------------------------------------------------------
REGISTRY="cgi.medsys.cloud"
NAMESPACE="mkm1971"
IMAGE_NAME="kamos"
IMAGE_REF="${REGISTRY}/${NAMESPACE}/${IMAGE_NAME}"
TAGS=("stable" "latest" "$(date +%Y%m%d)")

GREEN="\033[0;32m"
YELLOW="\033[1;33m"
RED="\033[0;31m"
NC="\033[0m"

log()  { echo -e "${GREEN}==>${NC} $*"; }
warn() { echo -e "${YELLOW}!! ${NC} $*"; }
err()  { echo -e "${RED}!! ${NC} $*" >&2; }

# ---- preflight -------------------------------------------------------------
log "Pre-flight checks"

if ! command -v brew >/dev/null 2>&1; then
    err "Homebrew is not installed. Install it first from https://brew.sh"
    exit 1
fi

for tool in podman cosign; do
    if ! command -v "$tool" >/dev/null 2>&1; then
        warn "$tool not found. Installing via brew..."
        brew install "$tool"
    fi
done

# ---- podman machine --------------------------------------------------------
log "Ensure podman machine is running"

if ! podman machine list --format '{{.Name}} {{.Running}}' | grep -q "true"; then
    if ! podman machine list --format '{{.Name}}' | grep -q .; then
        log "No podman machine yet - creating one (8 GB RAM, 80 GB disk)"
        podman machine init --cpus 6 --memory 8192 --disk-size 80
    fi
    log "Starting podman machine"
    podman machine start
fi

# ---- build ----------------------------------------------------------------
log "Build linux/amd64 image (this is the slow step on Apple Silicon)"

build_args=()
for t in "${TAGS[@]}"; do
    build_args+=(--tag "${IMAGE_REF}:${t}")
done

podman build \
    --platform=linux/amd64 \
    --pull=newer \
    "${build_args[@]}" \
    .

log "Build complete"
podman images | grep "${IMAGE_NAME}" || true

# ---- login ----------------------------------------------------------------
log "Login to Forgejo registry at ${REGISTRY}"
warn "When prompted: username = ${NAMESPACE}, password = your REGISTRY_TOKEN"

podman login "${REGISTRY}" --username "${NAMESPACE}"

# ---- push -----------------------------------------------------------------
log "Push image with all tags"

for t in "${TAGS[@]}"; do
    log "  pushing ${IMAGE_REF}:${t}"
    podman push "${IMAGE_REF}:${t}"
done

# ---- sign (optional, best-effort) -----------------------------------------
# Cosign on macOS sometimes can't find podman's auth credentials (they're at
# ~/.config/containers/auth.json instead of ~/.docker/config.json). We point
# it at podman's auth file and don't fail the script if signing breaks - the
# image is already pushed, signing is just a verification add-on.
if [ -f cosign.key ] && [ "${SKIP_SIGN:-0}" != "1" ]; then
    log "Sign image with cosign (best-effort)"

    # Tell cosign where podman stored credentials.
    PODMAN_AUTH="${HOME}/.config/containers/auth.json"
    if [ -f "${PODMAN_AUTH}" ]; then
        export DOCKER_CONFIG="${HOME}/.config/containers"
    fi

    for t in "${TAGS[@]}"; do
        digest=$(skopeo inspect \
            --authfile "${PODMAN_AUTH}" \
            --format '{{.Digest}}' \
            "docker://${IMAGE_REF}:${t}" 2>/dev/null || true)
        if [ -n "$digest" ]; then
            log "  signing ${IMAGE_REF}@${digest}"
            COSIGN_PASSWORD="" cosign sign --yes \
                --key cosign.key \
                "${IMAGE_REF}@${digest}" \
                || warn "Sign failed for tag ${t} (image still pushed and usable)"
        else
            warn "Could not get digest for tag ${t} - skipping sign"
        fi
    done
else
    warn "Skipping image signing (set SKIP_SIGN=0 with cosign.key present to enable)"
fi

# ---- done -----------------------------------------------------------------
echo
log "All done."
echo
echo "  Image:    ${IMAGE_REF}"
echo "  Tags:     ${TAGS[*]}"
echo
echo "  Switch your NVIDIA PC to it with:"
echo
echo "    sudo bootc switch ${IMAGE_REF}:stable"
echo "    sudo systemctl reboot"
echo