#!/usr/bin/env bash
set -u

APPFACTORY_ROOT="/opt/appfactory"
ENV_FILE="$APPFACTORY_ROOT/config/appfactory.env"

BACKUP_WARN_HOURS="${BACKUP_WARN_HOURS:-24}"
BACKUP_FAIL_HOURS="${BACKUP_FAIL_HOURS:-72}"

DISK_WARN_PERCENT="${DISK_WARN_PERCENT:-80}"
DISK_FAIL_PERCENT="${DISK_FAIL_PERCENT:-90}"

OK_COUNT=0
WARN_COUNT=0
FAIL_COUNT=0

ok(){ OK_COUNT=$((OK_COUNT+1)); echo "[OK]   $1"; }
warn(){ WARN_COUNT=$((WARN_COUNT+1)); echo "[WARN] $1"; }
fail(){ FAIL_COUNT=$((FAIL_COUNT+1)); echo "[FAIL] $1"; }
section(){ echo; echo "== $1 =="; }

check_command() {
  command -v "$1" >/dev/null 2>&1 && ok "Command available: $1" || fail "Command missing: $1"
}

load_env() {
  section "Environment"

  if [ ! -f "$ENV_FILE" ]; then
    fail "Env file missing: $ENV_FILE"
    return
  fi

  ok "Env file exists: $ENV_FILE"

  set -a
  # shellcheck disable=SC1090
  source "$ENV_FILE"
  set +a

  for key in APPFACTORY_UID APPFACTORY_GID APPFACTORY_DOCKER_GID; do
    [ -n "${!key:-}" ] && ok "$key=${!key}" || fail "$key is missing"
  done

  for key in APPFACTORY_DOMAIN APPFACTORY_PORTAL_DOMAIN APPFACTORY_GITEA_DOMAIN APPFACTORY_REGISTRY_DOMAIN; do
    [ -n "${!key:-}" ] && ok "$key=${!key}" || warn "$key is empty"
  done

  [ -n "${APPFACTORY_ENABLE_HTTPS:-}" ] && ok "APPFACTORY_ENABLE_HTTPS=$APPFACTORY_ENABLE_HTTPS" || warn "APPFACTORY_ENABLE_HTTPS is missing"

  for key in SMTP_HOST SMTP_PORT SMTP_USERNAME SMTP_FROM SMTP_PASSWORD; do
    [ -n "${!key:-}" ] && ok "$key configured" || warn "$key is empty"
  done

  if [ -n "${GOOGLE_CLIENT_ID:-}" ] && [ -n "${GOOGLE_CLIENT_SECRET:-}" ]; then
    ok "Google OAuth configured"
  else
    warn "Google OAuth not configured"
  fi
}

check_directories() {
  section "Directories"

  for dir in apps backups config data deploy gateway services templates tools workspace; do
    path="$APPFACTORY_ROOT/$dir"
    [ -d "$path" ] && ok "Directory exists: $path" || fail "Directory missing: $path"
  done
}

check_ownership() {
  section "Ownership"

  uid="${APPFACTORY_UID:-}"
  gid="${APPFACTORY_GID:-}"

  if [ -z "$uid" ] || [ -z "$gid" ]; then
    fail "Cannot check ownership because APPFACTORY_UID/GID is missing"
    return
  fi

  for path in "$APPFACTORY_ROOT" "$APPFACTORY_ROOT/data" "$APPFACTORY_ROOT/workspace" "$APPFACTORY_ROOT/backups"; do
    if [ ! -e "$path" ]; then
      fail "Path missing for ownership check: $path"
      continue
    fi

    actual_uid="$(stat -c '%u' "$path")"
    actual_gid="$(stat -c '%g' "$path")"

    if [ "$actual_uid" = "$uid" ] && [ "$actual_gid" = "$gid" ]; then
      ok "Ownership OK: $path ($actual_uid:$actual_gid)"
    else
      fail "Ownership mismatch: $path is $actual_uid:$actual_gid, expected $uid:$gid"
    fi
  done
}

check_docker() {
  section "Docker"

  check_command docker

  docker compose version >/dev/null 2>&1 && ok "docker compose available" || fail "docker compose not available"

  [ -S /var/run/docker.sock ] && ok "Docker socket exists" || fail "Docker socket missing"

  if getent group docker >/dev/null 2>&1; then
    docker_group_gid="$(getent group docker | cut -d: -f3)"
    ok "Docker group exists in current runtime with gid=$docker_group_gid"
  else
    warn "Docker group does not exist in current runtime"
  fi

  if [ -S /var/run/docker.sock ]; then
    docker_sock_gid="$(stat -c '%g' /var/run/docker.sock)"
    ok "Docker socket gid=$docker_sock_gid"

    if [ -n "${APPFACTORY_DOCKER_GID:-}" ] && [ "$docker_sock_gid" = "$APPFACTORY_DOCKER_GID" ]; then
      ok "APPFACTORY_DOCKER_GID matches docker socket gid"
    else
      fail "APPFACTORY_DOCKER_GID mismatch. env=${APPFACTORY_DOCKER_GID:-empty}, docker_sock_gid=$docker_sock_gid"
    fi
  fi

  docker ps >/dev/null 2>&1 && ok "docker ps works from host/runtime" || fail "docker ps failed from host/runtime"
}

check_containers() {
  section "Containers"

  for name in appfactory-portal appfactory-worker appfactory-monitor appfactory-webhook appfactory-gitea appfactory-registry appfactory-caddy; do
    if ! docker inspect "$name" >/dev/null 2>&1; then
      warn "Container missing: $name"
      continue
    fi

    state="$(docker inspect -f '{{.State.Status}}' "$name" 2>/dev/null || true)"
    health="$(docker inspect -f '{{if .State.Health}}{{.State.Health.Status}}{{else}}none{{end}}' "$name" 2>/dev/null || true)"

    if [ "$state" != "running" ]; then
      fail "Container not running: $name status=$state"
    elif [ "$health" = "unhealthy" ]; then
      fail "Container unhealthy: $name"
    else
      ok "Container running: $name health=$health"
    fi
  done
}

check_container_docker_access() {
  section "Container Docker Access"

  for name in appfactory-portal appfactory-worker appfactory-webhook; do
    if ! docker inspect "$name" >/dev/null 2>&1; then
      warn "Skipping docker access check, container missing: $name"
      continue
    fi

    if docker exec "$name" docker ps >/dev/null 2>&1; then
      ok "Docker access from container works: $name"
    else
      fail "Docker access from container failed: $name"
    fi
  done
}

find_portal_db() {
  candidates="$(find "$APPFACTORY_ROOT" -maxdepth 7 -type f \( -name '*.db' -o -name '*.sqlite' -o -name '*.sqlite3' \) 2>/dev/null || true)"

  for db in $candidates; do
    has_apps="$(sqlite3 "$db" "select name from sqlite_master where type='table' and name='apps';" 2>/dev/null || true)"
    has_jobs="$(sqlite3 "$db" "select name from sqlite_master where type='table' and name='jobs';" 2>/dev/null || true)"
    has_templates="$(sqlite3 "$db" "select name from sqlite_master where type='table' and name='app_templates';" 2>/dev/null || true)"

    if [ "$has_apps" = "apps" ] && [ "$has_jobs" = "jobs" ] && [ "$has_templates" = "app_templates" ]; then
      echo "$db"
      return 0
    fi
  done

  return 1
}

check_sqlite() {
  section "SQLite"

  check_command sqlite3

  db_path="$(find_portal_db || true)"

  if [ -z "$db_path" ]; then
    fail "Portal SQLite DB not found. No DB contains apps + jobs + app_templates."
    return
  fi

  ok "Portal SQLite DB found: $db_path"

  [ -r "$db_path" ] && ok "DB readable" || fail "DB not readable: $db_path"
  [ -w "$db_path" ] && ok "DB writable" || fail "DB not writable: $db_path"

  for table in apps app_templates jobs scheduled_scripts alert_rules alert_events; do
    exists="$(sqlite3 "$db_path" "select name from sqlite_master where type='table' and name='$table';" 2>/dev/null || true)"
    [ "$exists" = "$table" ] && ok "Table exists: $table" || fail "Table missing: $table"
  done

  template_count="$(sqlite3 "$db_path" "select count(*) from app_templates where is_enabled=1;" 2>/dev/null || echo 0)"
  if [ "$template_count" -gt 0 ] 2>/dev/null; then
    ok "Enabled app templates: $template_count"
    sqlite3 "$db_path" "select '- ' || coalesce(name, template) || ' [' || coalesce(template, '') || ']' from app_templates where is_enabled=1 order by 1;" 2>/dev/null || true
  else
    fail "No enabled app templates found"
  fi
}

check_alerting() {
  section "Alerting"

  alerts_dir="$APPFACTORY_ROOT/workspace/appfactory-tools/alerts"

  [ -d "$alerts_dir" ] && ok "Alert scripts directory exists: $alerts_dir" || { fail "Alert scripts directory missing: $alerts_dir"; return; }

  count="$(find "$alerts_dir" -maxdepth 1 -type f -name '*.sh' | wc -l | tr -d ' ')"
  if [ "$count" -gt 0 ]; then
    ok "Alert scripts found: $count"
    find "$alerts_dir" -maxdepth 1 -type f -name '*.sh' -printf '%f\n' | sort | sed 's/^/- /'
  else
    warn "No alert scripts found"
  fi
}

check_scheduler() {
  section "Scheduler"

  maintenance_dir="$APPFACTORY_ROOT/workspace/appfactory-tools/maintenance"

  [ -d "$maintenance_dir" ] && ok "Maintenance scripts directory exists: $maintenance_dir" || { fail "Maintenance scripts directory missing: $maintenance_dir"; return; }

  count="$(find "$maintenance_dir" -maxdepth 1 -type f -name '*.sh' | wc -l | tr -d ' ')"
  if [ "$count" -gt 0 ]; then
    ok "Maintenance scripts found: $count"
    find "$maintenance_dir" -maxdepth 1 -type f -name '*.sh' -printf '%f\n' | sort | sed 's/^/- /'
  else
    warn "No maintenance scripts found"
  fi
}

check_disk_space() {
  section "Disk Space"

  for path in "$APPFACTORY_ROOT" "$APPFACTORY_ROOT/data" "$APPFACTORY_ROOT/backups"; do
    if [ ! -d "$path" ]; then
      fail "Cannot check disk space, path missing: $path"
      continue
    fi

    used_percent="$(df -P "$path" | awk 'NR==2 {gsub("%","",$5); print $5}')"
    available="$(df -hP "$path" | awk 'NR==2 {print $4}')"
    mountpoint="$(df -P "$path" | awk 'NR==2 {print $6}')"

    if [ -z "$used_percent" ]; then
      warn "Could not read disk usage for $path"
      continue
    fi

    if [ "$used_percent" -ge "$DISK_FAIL_PERCENT" ] 2>/dev/null; then
      fail "Disk usage critical for $path: ${used_percent}% used, available=$available, mount=$mountpoint"
    elif [ "$used_percent" -ge "$DISK_WARN_PERCENT" ] 2>/dev/null; then
      warn "Disk usage high for $path: ${used_percent}% used, available=$available, mount=$mountpoint"
    else
      ok "Disk usage OK for $path: ${used_percent}% used, available=$available, mount=$mountpoint"
    fi
  done
}

check_backup_freshness() {
  section "Backup Freshness"

  backup_dir="$APPFACTORY_ROOT/backups"

  if [ ! -d "$backup_dir" ]; then
    fail "Backup directory missing: $backup_dir"
    return
  fi

  latest_backup="$(find "$backup_dir" -type f \
    \( -name '*.tar' -o -name '*.tar.gz' -o -name '*.tgz' -o -name '*.zip' -o -name '*.db' -o -name '*.sqlite' -o -name '*.sqlite3' \) \
    -printf '%T@ %p\n' 2>/dev/null | sort -nr | head -n 1 | cut -d' ' -f2- || true)"

  if [ -z "$latest_backup" ]; then
    warn "No backup files found in $backup_dir"
    return
  fi

  now_epoch="$(date +%s)"
  backup_epoch="$(stat -c '%Y' "$latest_backup")"
  age_seconds=$((now_epoch - backup_epoch))
  age_hours=$((age_seconds / 3600))

  backup_size="$(du -h "$latest_backup" 2>/dev/null | awk '{print $1}')"
  backup_time="$(date -d "@$backup_epoch" '+%Y-%m-%d %H:%M:%S %z' 2>/dev/null || date -r "$backup_epoch" '+%Y-%m-%d %H:%M:%S' 2>/dev/null || echo "$backup_epoch")"

  if [ "$age_hours" -ge "$BACKUP_FAIL_HOURS" ]; then
    warn "Latest backup is too old: ${age_hours}h, file=$latest_backup, size=$backup_size, time=$backup_time"
  elif [ "$age_hours" -ge "$BACKUP_WARN_HOURS" ]; then
    warn "Latest backup is older than warning threshold: ${age_hours}h, file=$latest_backup, size=$backup_size, time=$backup_time"
  else
    ok "Latest backup fresh: ${age_hours}h, file=$latest_backup, size=$backup_size, time=$backup_time"
  fi
}

check_gitea_readiness() {
  section "Gitea Readiness"

  gitea_container="appfactory-gitea"

  if docker inspect "$gitea_container" >/dev/null 2>&1; then
    state="$(docker inspect -f '{{.State.Status}}' "$gitea_container" 2>/dev/null || true)"
    [ "$state" = "running" ] && ok "Gitea container running" || fail "Gitea container not running: $state"
  else
    fail "Gitea container missing: $gitea_container"
  fi

  gitea_db_candidates=(
    "$APPFACTORY_ROOT/data/gitea/gitea/gitea.db"
    "$APPFACTORY_ROOT/data/gitea/gitea.db"
  )

  gitea_db=""
  for candidate in "${gitea_db_candidates[@]}"; do
    if [ -f "$candidate" ]; then
      gitea_db="$candidate"
      break
    fi
  done

  if [ -n "$gitea_db" ]; then
    ok "Gitea DB exists: $gitea_db"
    [ -r "$gitea_db" ] && ok "Gitea DB readable" || fail "Gitea DB not readable: $gitea_db"
    [ -w "$gitea_db" ] && ok "Gitea DB writable" || warn "Gitea DB not writable from current runtime: $gitea_db"

    if command -v sqlite3 >/dev/null 2>&1; then
      repo_table="$(sqlite3 "$gitea_db" "select name from sqlite_master where type='table' and name='repository';" 2>/dev/null || true)"
      [ "$repo_table" = "repository" ] && ok "Gitea repository table exists" || warn "Gitea repository table not found"
    fi
  else
    warn "Gitea DB not found in expected paths"
  fi

  repo_dirs=(
    "$APPFACTORY_ROOT/data/gitea/git/repositories"
    "$APPFACTORY_ROOT/data/gitea/gitea-repositories"
    "$APPFACTORY_ROOT/data/gitea/repositories"
  )

  repo_dir_found=""
  for candidate in "${repo_dirs[@]}"; do
    if [ -d "$candidate" ]; then
      repo_dir_found="$candidate"
      break
    fi
  done

  if [ -n "$repo_dir_found" ]; then
    ok "Gitea repository storage exists: $repo_dir_found"
  else
    warn "Gitea repository storage not found in expected paths"
  fi
}

check_registry_readiness() {
  section "Registry Readiness"

  registry_container="appfactory-registry"

  if docker inspect "$registry_container" >/dev/null 2>&1; then
    state="$(docker inspect -f '{{.State.Status}}' "$registry_container" 2>/dev/null || true)"
    [ "$state" = "running" ] && ok "Registry container running" || fail "Registry container not running: $state"
  else
    fail "Registry container missing: $registry_container"
  fi

  registry_dirs=(
    "$APPFACTORY_ROOT/data/registry"
    "$APPFACTORY_ROOT/data/docker-registry"
    "$APPFACTORY_ROOT/registry"
  )

  registry_dir_found=""
  for candidate in "${registry_dirs[@]}"; do
    if [ -d "$candidate" ]; then
      registry_dir_found="$candidate"
      break
    fi
  done

  if [ -n "$registry_dir_found" ]; then
    ok "Registry storage exists: $registry_dir_found"
    [ -r "$registry_dir_found" ] && ok "Registry storage readable" || fail "Registry storage not readable: $registry_dir_found"
    [ -w "$registry_dir_found" ] && ok "Registry storage writable" || warn "Registry storage not writable from current runtime: $registry_dir_found"
  else
    warn "Registry storage not found in expected paths"
  fi
}

check_caddy_readiness() {
  section "Caddy Readiness"

  caddyfile="$APPFACTORY_ROOT/gateway/Caddyfile"

  if [ ! -f "$caddyfile" ]; then
    fail "Caddyfile missing: $caddyfile"
    return
  fi

  ok "Caddyfile exists: $caddyfile"

  if docker inspect appfactory-caddy >/dev/null 2>&1; then
    state="$(docker inspect -f '{{.State.Status}}' appfactory-caddy 2>/dev/null || true)"
    [ "$state" = "running" ] && ok "Caddy container running" || fail "Caddy container not running: $state"

    if docker exec appfactory-caddy caddy validate --config /etc/caddy/Caddyfile >/tmp/appfactory-caddy-validate.log 2>&1; then
      ok "Caddyfile validates inside container"
    else
      fail "Caddyfile validation failed"
      sed 's/^/[caddy] /' /tmp/appfactory-caddy-validate.log || true
    fi
  else
    fail "Caddy container missing: appfactory-caddy"
  fi

  if [ "${APPFACTORY_ENABLE_HTTPS:-false}" = "true" ]; then
    if [ -n "${APPFACTORY_PORTAL_DOMAIN:-}" ] || [ -n "${APPFACTORY_GITEA_DOMAIN:-}" ] || [ -n "${APPFACTORY_REGISTRY_DOMAIN:-}" ]; then
      ok "HTTPS mode requested with at least one domain configured"
    else
      fail "HTTPS mode enabled but no domains are configured"
    fi

    if grep -q '^:80[[:space:]]*{' "$caddyfile"; then
      fail "HTTPS mode enabled but Caddyfile still uses :80 catch-all block"
    else
      ok "Caddyfile is not using :80-only mode"
    fi
  else
    if grep -q '^:80[[:space:]]*{' "$caddyfile"; then
      ok "HTTP-only Caddyfile mode active"
    else
      warn "HTTPS disabled but Caddyfile does not contain :80 catch-all block"
    fi
  fi
}

check_readiness_flags() {
  section "Readiness Flags"

  [ "${APPFACTORY_ENABLE_HTTPS:-false}" = "true" ] && ok "HTTPS enabled" || warn "HTTPS disabled"

  [ -n "${APPFACTORY_DOMAIN:-}" ] && ok "Base domain configured: $APPFACTORY_DOMAIN" || warn "Base domain not configured"
  [ -n "${APPFACTORY_PORTAL_DOMAIN:-}" ] && ok "Portal domain configured: $APPFACTORY_PORTAL_DOMAIN" || warn "Portal domain not configured"
  [ -n "${APPFACTORY_GITEA_DOMAIN:-}" ] && ok "Gitea domain configured: $APPFACTORY_GITEA_DOMAIN" || warn "Gitea domain not configured"
  [ -n "${APPFACTORY_REGISTRY_DOMAIN:-}" ] && ok "Registry domain configured: $APPFACTORY_REGISTRY_DOMAIN" || warn "Registry domain not configured"
}

main() {
  echo "APPFACTORY PREFLIGHT CHECK"
  echo "Root: $APPFACTORY_ROOT"

  load_env
  check_directories
  check_ownership
  check_docker
  check_containers
  check_container_docker_access
  check_sqlite
  check_alerting
  check_scheduler
  check_disk_space
  check_backup_freshness
  check_gitea_readiness
  check_registry_readiness
  check_caddy_readiness
  check_readiness_flags

  echo
  echo "== Summary =="
  echo "OK:   $OK_COUNT"
  echo "WARN: $WARN_COUNT"
  echo "FAIL: $FAIL_COUNT"

  if [ "$FAIL_COUNT" -eq 0 ]; then
    echo
    echo "APPFACTORY PREFLIGHT: READY"
    exit 0
  fi

  echo
  echo "APPFACTORY PREFLIGHT: NOT READY"
  exit 1
}

main "$@"