#!/usr/bin/env bash
# =============================================================================
# felhom-controller — Docker image build script
# =============================================================================
# Location: /mnt/5_hdd/felhom.eu/build/felhom-controller/build.sh (moved off the DooPlex SSD 2026-07-18)
#
# Copies source from the git repo, syncs app assets, and builds the image.
# Build artifacts stay here — the git repo stays clean.
#
# Usage:
#   ./build.sh                    # Build for current platform, tag as :dev
#   ./build.sh 0.1.0              # Build with version tag
#   ./build.sh 0.1.0 --push       # Build + push to Gitea registry
#   ./build.sh 0.1.0 --multiarch  # Build amd64+arm64 + push
# =============================================================================
set -euo pipefail

# --- Configuration (edit these if your paths differ) ---
# The default is the shared DooPlex clone, and the release runbook names it. It is overridable
# because that clone is shared: when another session has work in progress in it, the clean-tree gate
# rightly forbids building over them, and the way to ship is a clean clone at the pushed commit —
# not stashing somebody else's work. Set FELHOM_REPO_DIR to that clone.
REPO_DIR="${FELHOM_REPO_DIR:-/mnt/5_hdd/felhom.eu/git/felhom-controller}"
CONTROLLER_SRC="${REPO_DIR}/controller"
WEBSITE_ASSETS_DIR="/mnt/5_hdd/felhom.eu/git/felhom.eu/website/assets"
REGISTRY="gitea.dooplex.hu/admin"
IMAGE="${REGISTRY}/felhom-controller"

# Build workspace — a temp directory next to this script, NOT in the git repo
SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
BUILD_DIR="${SCRIPT_DIR}/workspace"

# --- Parse arguments ---
VERSION="${1:-dev}"
ACTION="${2:-}"  # --push or --multiarch

# --- Colors ---
RED='\033[0;31m'; GREEN='\033[0;32m'; YELLOW='\033[1;33m'; CYAN='\033[0;36m'; NC='\033[0m'
info()  { echo -e "${GREEN}[INFO]${NC}  $*"; }
warn()  { echo -e "${YELLOW}[WARN]${NC}  $*"; }
error() { echo -e "${RED}[ERROR]${NC} $*"; }
step()  { echo -e "${CYAN}[STEP]${NC}  $*"; }

# --- Pre-flight checks ---
if [[ ! -d "${CONTROLLER_SRC}" ]]; then
    error "Controller source not found: ${CONTROLLER_SRC}"
    error "Clone the repo first: git clone https://gitea.dooplex.hu/admin/felhom-controller.git ${REPO_DIR}"
    exit 1
fi

if ! command -v docker &>/dev/null; then
    error "Docker not found."
    exit 1
fi

# Git metadata from the repo
GIT_COMMIT="unknown"
if [[ -d "${REPO_DIR}/.git" ]]; then
    GIT_COMMIT=$(cd "${REPO_DIR}" && git rev-parse --short HEAD 2>/dev/null || echo "unknown")
fi

echo ""
info "╔══════════════════════════════════════╗"
info "║  felhom-controller image builder     ║"
info "╚══════════════════════════════════════╝"
info "Version:    ${VERSION}"
info "Commit:     ${GIT_COMMIT}"
info "Repo:       ${REPO_DIR}"
info "Source:     ${CONTROLLER_SRC}"
info "Build dir:  ${BUILD_DIR}"
info "Image:      ${IMAGE}:${VERSION}"
echo ""

# =========================================================================
# A VERSION NUMBER IS PUSHED ONCE (v0.316.0)
# =========================================================================
# 0.315.0 was built and pushed THREE times from three different commits. A box that pulled between
# the first and the last runs different code under the same number — and will never fetch the fix,
# because to the box, and to the floor, that number is already current (`09-update-architecture.md`:
# a box compares VERSIONS, and re-pulls a tag it already has only when the tag changes). Nothing in
# the build stopped it. This does.
#
# The check runs BEFORE the build, so a refusal costs no minutes. A registry that cannot be reached
# is a REFUSAL too: the point is to prove the tag is new, and "I could not ask" is not that proof.
# Local builds (no --push) are unaffected — reusing a version while iterating is the normal case.
#
# `docker manifest inspect` is the probe, so a test can put a fake `docker` on PATH
# (scripts/test_build_push_once.sh).
if [[ "${ACTION}" == "--push" || "${ACTION}" == "--multiarch" ]]; then
    step "0/4 — Checking the registry: is ${VERSION} already published?"
    # `set -e` is on, and a failing command substitution would abort the script before the rc is
    # ever read — which would turn "the registry said no such tag" into a silent exit. The `|| true`
    # keeps the failure for us to classify; that classification is the whole check.
    probe_rc=0
    probe_out=$(docker manifest inspect "${IMAGE}:${VERSION}" 2>&1) || probe_rc=$?
    if [[ ${probe_rc} -eq 0 ]]; then
        error "${IMAGE}:${VERSION} already exists in the registry — bump the version."
        error "A version number is pushed once. Two images under one number mean a box can run"
        error "either of them and never learn the difference. If this is a fix for something already"
        error "pushed, release it as the next patch version instead."
        exit 1
    fi
    # Absent is the ONLY other acceptable answer. Anything that is not a clean "not found" (the
    # registry is down, the login expired, DNS failed) leaves the question unanswered, and an
    # unanswered question is a refusal.
    if ! grep -qiE 'no such manifest|manifest unknown|not found|does not exist|NAME_UNKNOWN|MANIFEST_UNKNOWN' <<<"${probe_out}"; then
        error "Could not establish whether ${IMAGE}:${VERSION} exists — refusing to build."
        error "The registry answered: ${probe_out}"
        error "Proving the tag is new is the point of this check; 'I could not ask' is not that proof."
        exit 1
    fi
    info "${VERSION} is not present in the registry — proceeding."

    # AND THE TREE IT BUILDS FROM MUST BE CLEAN AND PUSHED.
    #
    # Until v0.316.3 this was a sentence in a runbook, and a rule without a mechanism is a wish. It
    # cost a bad push the same evening it was written down: the shared clone had 31 files of another
    # session's work in progress, and a build from it put their unreleased code into a published
    # image under my version number. Nobody deployed it; that was luck, not a control.
    #
    # Two questions, both of which must be YES:
    #   is every tracked file committed?      — otherwise the image holds something git does not
    #   is HEAD what origin/main has?         — otherwise the image holds something nobody can fetch
    # „An unpushed change does not exist" (workspace CLAUDE.md), and an image built from one is a
    # thing that exists and cannot be reproduced.
    if [[ -d "${REPO_DIR}/.git" ]]; then
        dirty=$(cd "${REPO_DIR}" && git status --porcelain 2>/dev/null | wc -l)
        if [[ "${dirty}" -ne 0 ]]; then
            error "${REPO_DIR} has ${dirty} uncommitted change(s) — refusing to push a build from it."
            error "An image built from a dirty tree cannot be reproduced, and on a SHARED clone it"
            error "may carry work that is not yours. Commit and push, or build from a clean clone"
            error "with FELHOM_REPO_DIR pointing at it."
            (cd "${REPO_DIR}" && git status --porcelain | head -10 | sed 's/^/          /')
            exit 1
        fi
        head_sha=$(cd "${REPO_DIR}" && git rev-parse HEAD 2>/dev/null || echo unknown)
        main_sha=$(cd "${REPO_DIR}" && git rev-parse origin/main 2>/dev/null || echo unknown)
        if [[ "${head_sha}" != "${main_sha}" ]]; then
            error "${REPO_DIR} is not at origin/main — refusing to push."
            error "  HEAD        ${head_sha}"
            error "  origin/main ${main_sha}"
            error "An unpushed change does not exist; an image built from one cannot be fetched again."
            exit 1
        fi
        info "Source tree is clean and at origin/main."
    else
        error "${REPO_DIR} is not a git checkout — refusing to push a build whose source cannot be identified."
        exit 1
    fi
fi

# =========================================================================
# Step 1: Prepare clean build workspace
# =========================================================================
step "1/4 — Preparing build workspace..."

rm -rf "${BUILD_DIR}"
mkdir -p "${BUILD_DIR}"

# Copy the entire controller directory (preserving subdirectory structure)
cp -a "${CONTROLLER_SRC}/." "${BUILD_DIR}/"

# Verify the expected Go package structure exists
MISSING=()
for required in cmd/controller/main.go internal/config/config.go internal/stacks/manager.go internal/api/router.go internal/web/server.go; do
    if [[ ! -f "${BUILD_DIR}/${required}" ]]; then
        MISSING+=("${required}")
    fi
done

if [[ ${#MISSING[@]} -gt 0 ]]; then
    error "Directory structure check FAILED. Missing files:"
    for f in "${MISSING[@]}"; do
        error "  ✗ ${f}"
    done
    error ""
    error "The Go source must be in package subdirectories, not flat."
    error "Run the restructure script first:"
    error "  cd ${CONTROLLER_SRC} && bash restructure.sh"
    error "  git add -A && git commit -m 'Restructure into Go package dirs'"
    rm -rf "${BUILD_DIR}"
    exit 1
fi

GO_COUNT=$(find "${BUILD_DIR}" -name '*.go' | wc -l)
info "Source copied: ${GO_COUNT} Go files"

# =========================================================================
# Step 2: Sync app assets (logos + screenshots)
# =========================================================================
step "2/4 — Syncing app assets..."

mkdir -p "${BUILD_DIR}/assets"

if [[ -d "${WEBSITE_ASSETS_DIR}" ]]; then
    # Count before copy
    SVG_N=$(find "${WEBSITE_ASSETS_DIR}" -maxdepth 1 -name '*-logo.svg' 2>/dev/null | wc -l)
    PNG_N=$(find "${WEBSITE_ASSETS_DIR}" -maxdepth 1 -name '*-logo.png' 2>/dev/null | wc -l)
    SS_N=$(find "${WEBSITE_ASSETS_DIR}" -maxdepth 1 -name '*-screenshot-*.webp' 2>/dev/null | wc -l)

    cp "${WEBSITE_ASSETS_DIR}"/*-logo.svg "${BUILD_DIR}/assets/" 2>/dev/null || true
    cp "${WEBSITE_ASSETS_DIR}"/*-logo.png "${BUILD_DIR}/assets/" 2>/dev/null || true
    cp "${WEBSITE_ASSETS_DIR}"/*-screenshot-*.webp "${BUILD_DIR}/assets/" 2>/dev/null || true

    TOTAL=$(find "${BUILD_DIR}/assets" -type f ! -name 'README.md' 2>/dev/null | wc -l)
    info "Synced ${TOTAL} assets (${SVG_N} SVG + ${PNG_N} PNG logos, ${SS_N} screenshots)"
else
    warn "Website assets not found: ${WEBSITE_ASSETS_DIR}"
    warn "Building without logos/screenshots. Set WEBSITE_ASSETS_DIR if needed."
fi

# =========================================================================
# Step 3: Run go mod tidy (to generate go.sum if missing)
# =========================================================================
step "3/4 — Preparing Go modules..."

cd "${BUILD_DIR}"

# The Dockerfile handles go mod download internally, but verify go.mod exists
if [[ ! -f "go.mod" ]]; then
    error "go.mod not found in build workspace!"
    exit 1
fi

# If go is installed locally, run tidy to catch issues early
if command -v go &>/dev/null; then
    info "Running go mod tidy..."
    go mod tidy 2>&1 || warn "go mod tidy had issues (Docker build may still work)"
else
    info "Go not installed locally — Docker build stage will handle dependencies."
fi

# =========================================================================
# Step 4: Docker build
# =========================================================================
step "4/4 — Building Docker image..."

BUILD_ARGS=(
    --build-arg "VERSION=${VERSION}"
    --build-arg "GIT_COMMIT=${GIT_COMMIT}"
)

case "${ACTION}" in
    --push)
        info "Building for current platform + pushing..."
        docker build "${BUILD_ARGS[@]}" \
            -t "${IMAGE}:${VERSION}" \
            -t "${IMAGE}:latest" \
            .

        info "Pushing..."
        docker push "${IMAGE}:${VERSION}"
        docker push "${IMAGE}:latest"
        ;;

    --multiarch)
        info "Building multi-arch (amd64 + arm64) + pushing..."

        # Ensure buildx builder exists
        if ! docker buildx inspect felhom-builder &>/dev/null; then
            info "Creating buildx builder (one-time setup)..."
            docker buildx create --name felhom-builder --use --bootstrap
        else
            docker buildx use felhom-builder
        fi

        docker buildx build "${BUILD_ARGS[@]}" \
            --platform linux/amd64,linux/arm64 \
            -t "${IMAGE}:${VERSION}" \
            -t "${IMAGE}:latest" \
            --push \
            .
        ;;

    *)
        info "Building for current platform (local only)..."
        docker build "${BUILD_ARGS[@]}" \
            -t "${IMAGE}:${VERSION}" \
            -t "${IMAGE}:latest" \
            .
        ;;
esac

# =========================================================================
# Summary
# =========================================================================
echo ""
info "╔══════════════════════════════════════╗"
info "║  Build complete ✓                    ║"
info "╚══════════════════════════════════════╝"
info "Image: ${IMAGE}:${VERSION}"

# Show image size if available locally
SIZE=$(docker image inspect "${IMAGE}:${VERSION}" --format='{{.Size}}' 2>/dev/null || echo "")
if [[ -n "${SIZE}" ]]; then
    SIZE_HUMAN=$(numfmt --to=iec "${SIZE}" 2>/dev/null || echo "${SIZE} bytes")
    info "Size:  ${SIZE_HUMAN}"
fi

echo ""
if [[ "${ACTION}" == "" ]]; then
    info "Image is local only. To push:"
    info "  ./build.sh ${VERSION} --push        # current arch"
    info "  ./build.sh ${VERSION} --multiarch   # amd64 + arm64"
fi