#!/usr/bin/env bash
set -euo pipefail

# ============================================================================
# build-and-push.sh
# Location: repo root (e.g. /docker/develop/backup-monitoring)
#
# Purpose:
# - Automatic version bump:
#     1 = patch, 2 = minor, 3 = major, t = test
# - Test builds: only update :dev (no commit/tag)
# - Release builds: update version.txt, commit, tag, push (to the current branch)
# - Build & push Docker images for each service under ./compose/*
# - Preflight checks: Docker daemon up, logged in to registry, valid names/tags
# - Summary: show all images + tags built and pushed
# - Branch visibility:
#     - Shows currently checked out branch (authoritative)
#     - Reads .last-branch for info (if present) when BRANCH is not set
#     - Writes the current branch back to .last-branch at the end
#
# Usage:
#   BRANCH=<branch> ./build-and-push.sh [bump]   # BRANCH is optional; informative only
#   ./build-and-push.sh [bump]
# If [bump] is omitted, you will be prompted (default = t).
#
# Tagging rules:
# - Release build (1/2/3): push :<version>, :dev, :latest
# - Test build (t): push only :dev (no :latest, no version tag)
# ============================================================================

DOCKER_REGISTRY="gitea.oskamp.info"
DOCKER_NAMESPACE="ivooskamp"

VERSION_FILE="version.txt"
START_VERSION="v0.1.0"
COMPOSE_DIR="containers"
LAST_BRANCH_FILE=".last-branch"   # stored in repo root

# --- Input: prompt if missing ------------------------------------------------
BUMP="${1:-}"
if [[ -z "${BUMP}" ]]; then
  echo "Select bump type: [1] patch, [2] minor, [3] major, [t] test (default: t)"
  read -r BUMP
  BUMP="${BUMP:-t}"
fi

if [[ "$BUMP" != "1" && "$BUMP" != "2" && "$BUMP" != "3" && "$BUMP" != "t" ]]; then
  echo "[ERROR] Unknown bump type '$BUMP' (use 1, 2, 3, or t)."
  exit 1
fi

# --- Helpers -----------------------------------------------------------------
read_version() {
  if [[ -f "$VERSION_FILE" ]]; then
    tr -d ' \t\n\r' < "$VERSION_FILE"
  else
    echo "$START_VERSION"
  fi
}

write_version() {
  echo "$1" > "$VERSION_FILE"
}

bump_version() {
  local cur="$1"
  local kind="$2"
  local core="${cur#v}"
  IFS='.' read -r MA MI PA <<< "$core"
  case "$kind" in
    1) PA=$((PA + 1));;
    2) MI=$((MI + 1)); PA=0;;
    3) MA=$((MA + 1)); MI=0; PA=0;;
    *) echo "[ERROR] Unknown bump kind"; exit 1;;
  esac
  echo "v${MA}.${MI}.${PA}"
}

check_docker_ready() {
  if ! docker info >/dev/null 2>&1; then
    echo "[ERROR] Docker daemon not reachable. Is Docker running and do you have permission to use it?"
    exit 1
  fi
}

ensure_registry_login() {
  local cfg="${HOME}/.docker/config.json"
  if [[ ! -f "$cfg" ]]; then
    echo "[ERROR] Docker config not found at $cfg. Please login:  docker login ${DOCKER_REGISTRY}"
    exit 1
  fi
  if ! grep -q "\"${DOCKER_REGISTRY}\"" "$cfg"; then
    echo "[ERROR] No registry auth found for ${DOCKER_REGISTRY}. Please run:  docker login ${DOCKER_REGISTRY}"
    exit 1
  fi
}

validate_repo_component() {
  local comp="$1"
  if [[ ! "$comp" =~ ^[a-z0-9]+([._-][a-z0-9]+)*$ ]]; then
    echo "[ERROR] Invalid repository component '$comp'."
    echo "        Must match: ^[a-z0-9]+([._-][a-z0-9]+)*$ (lowercase, digits, ., _, - as separators)."
    return 1
  fi
}

validate_tag() {
  local tag="$1"
  local len="${#tag}"
  if (( len < 1 || len > 128 )); then
    echo "[ERROR] Invalid tag length ($len). Must be between 1 and 128 characters."
    return 1
  fi
  if [[ ! "$tag" =~ ^[A-Za-z0-9_][A-Za-z0-9_.-]*$ ]]; then
    echo "[ERROR] Invalid tag '$tag'. Allowed: [A-Za-z0-9_.-], must start with alphanumeric or underscore."
    return 1
  fi
}

# --- Preflight ---------------------------------------------------------------
if [[ ! -d ".git" ]]; then
  echo "[ERROR] Not a git repository (.git missing)."
  exit 1
fi

if [[ ! -d "$COMPOSE_DIR" ]]; then
  echo "[ERROR] '$COMPOSE_DIR' directory missing. Expected ./compose/<service>/ with a Dockerfile."
  exit 1
fi

check_docker_ready
ensure_registry_login
validate_repo_component "$DOCKER_NAMESPACE"

# Detect currently checked out branch (authoritative for this script)
DETECTED_BRANCH="$(git branch --show-current 2>/dev/null || true)"
if [[ -z "$DETECTED_BRANCH" ]]; then
  DETECTED_BRANCH="$(git symbolic-ref --quiet --short HEAD 2>/dev/null || true)"
fi
if [[ -z "$DETECTED_BRANCH" ]]; then
  # Try to derive from upstream
  UPSTREAM_REF_DERIVED="$(git rev-parse --abbrev-ref --symbolic-full-name @{u} 2>/dev/null || true)"
  if [[ -n "$UPSTREAM_REF_DERIVED" ]]; then
    DETECTED_BRANCH="${UPSTREAM_REF_DERIVED#origin/}"
  fi
fi
if [[ -z "$DETECTED_BRANCH" ]]; then
  DETECTED_BRANCH="main"
fi

# Optional signals: BRANCH env and .last-branch (informational only)
ENV_BRANCH="${BRANCH:-}"
LAST_BRANCH_FILE_PATH="$(pwd)/$LAST_BRANCH_FILE"
LAST_BRANCH_VALUE=""
if [[ -z "$ENV_BRANCH" && -f "$LAST_BRANCH_FILE_PATH" ]]; then
  LAST_BRANCH_VALUE="$(tr -d ' \t\n\r' < "$LAST_BRANCH_FILE_PATH")"
fi

UPSTREAM_REF="$(git rev-parse --abbrev-ref --symbolic-full-name @{u} 2>/dev/null || echo "origin/$DETECTED_BRANCH")"
HEAD_SHA="$(git rev-parse --short HEAD 2>/dev/null || echo "unknown")"

echo "[INFO] Repo:             $(pwd)"
echo "[INFO] Current branch:   $DETECTED_BRANCH"
echo "[INFO] Upstream:         $UPSTREAM_REF"
echo "[INFO] HEAD (sha):       $HEAD_SHA"

if [[ -n "$ENV_BRANCH" && "$ENV_BRANCH" != "$DETECTED_BRANCH" ]]; then
  echo "[WARNING] BRANCH='$ENV_BRANCH' differs from checked out branch '$DETECTED_BRANCH'."
  echo "[WARNING] This script does not switch branches; continuing on '$DETECTED_BRANCH'."
fi

if [[ -n "$LAST_BRANCH_VALUE" && "$LAST_BRANCH_VALUE" != "$DETECTED_BRANCH" && -z "$ENV_BRANCH" ]]; then
  echo "[INFO] .last-branch suggests '$LAST_BRANCH_VALUE', but current checkout is '$DETECTED_BRANCH'."
  echo "[INFO] If you intended to build '$LAST_BRANCH_VALUE', switch branches first (use update-and-build.sh)."
fi

# --- Versioning --------------------------------------------------------------
CURRENT_VERSION="$(read_version)"
NEW_VERSION="$CURRENT_VERSION"
DO_TAG_AND_BUMP=true

if [[ "$BUMP" == "t" ]]; then
  echo "[INFO] Test build: keeping version $CURRENT_VERSION; will only update :dev."
  DO_TAG_AND_BUMP=false
else
  NEW_VERSION="$(bump_version "$CURRENT_VERSION" "$BUMP")"
  echo "[INFO] New version: $NEW_VERSION"
fi

if $DO_TAG_AND_BUMP; then
  validate_tag "$NEW_VERSION"
  validate_tag "latest"
fi
validate_tag "dev"

# --- Version update + VCS ops (release builds only) --------------------------
if $DO_TAG_AND_BUMP; then
  echo "[INFO] Writing $NEW_VERSION to $VERSION_FILE"
  write_version "$NEW_VERSION"

  echo "[INFO] Git add + commit (branch: $DETECTED_BRANCH)"
  git add "$VERSION_FILE"
  git commit -m "Release $NEW_VERSION on branch $DETECTED_BRANCH (bump type $BUMP)"

  echo "[INFO] Git tag $NEW_VERSION"
  git tag -a "$NEW_VERSION" -m "Release $NEW_VERSION"

  echo "[INFO] Git push + tags"
  git push origin "$DETECTED_BRANCH"
  git push --tags
else
  echo "[INFO] Skipping commit/tagging (test build)."
fi

# --- Build & push per service ------------------------------------------------
shopt -s nullglob
services=( "$COMPOSE_DIR"/* )
if [[ ${#services[@]} -eq 0 ]]; then
  echo "[ERROR] No services found under $COMPOSE_DIR"
  exit 1
fi

BUILT_IMAGES=()

for svc_path in "${services[@]}"; do
  [[ -d "$svc_path" ]] || continue
  svc="$(basename "$svc_path")"
  dockerfile="$svc_path/Dockerfile"

  validate_repo_component "$svc"

  if [[ ! -f "$dockerfile" ]]; then
    echo "[WARNING] Skipping '${svc}': Dockerfile not found in ${svc_path}"
    continue
  fi

  IMAGE_BASE="${DOCKER_REGISTRY}/${DOCKER_NAMESPACE}/${svc}"

  if $DO_TAG_AND_BUMP; then
    echo "============================================================"
    echo "[INFO] Building ${svc} -> tags: ${NEW_VERSION}, dev, latest"
    echo "============================================================"
    docker build \
      -t "${IMAGE_BASE}:${NEW_VERSION}" \
      -t "${IMAGE_BASE}:dev" \
      -t "${IMAGE_BASE}:latest" \
      "$svc_path"

    docker push "${IMAGE_BASE}:${NEW_VERSION}"
    docker push "${IMAGE_BASE}:dev"
    docker push "${IMAGE_BASE}:latest"

    BUILT_IMAGES+=("${IMAGE_BASE}:${NEW_VERSION}" "${IMAGE_BASE}:dev" "${IMAGE_BASE}:latest")
  else
    echo "============================================================"
    echo "[INFO] Test build ${svc} -> tag: dev"
    echo "============================================================"
    docker build -t "${IMAGE_BASE}:dev" "$svc_path"
    docker push "${IMAGE_BASE}:dev"
    BUILT_IMAGES+=("${IMAGE_BASE}:dev")
  fi
done

# --- Persist current branch to .last-branch ----------------------------------
# (This helps script 1 to preselect next time, and is informative if you run script 2 standalone)
echo "$DETECTED_BRANCH" > "$LAST_BRANCH_FILE_PATH"

# --- Summary -----------------------------------------------------------------
echo ""
echo "============================================================"
echo "[SUMMARY] Build & push complete (branch: $DETECTED_BRANCH)"
if $DO_TAG_AND_BUMP; then
  echo "[INFO] Release version: $NEW_VERSION"
else
  echo "[INFO] Test build (no version bump)"
fi
echo "[INFO] Images pushed:"
for img in "${BUILT_IMAGES[@]}"; do
  echo "  - $img"
done
echo "============================================================"