#!/bin/bash
#
# AzerothCore Build Script
# Handles all module compilation and image building for custom configurations
#

set -euo pipefail

ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
ENV_PATH="$ROOT_DIR/.env"
ASSUME_YES=0
FORCE_REBUILD=0
SKIP_SOURCE_SETUP=0
CUSTOM_SOURCE_PATH=""
MIGRATE_HOST=""
MIGRATE_USER=""
MIGRATE_PORT="22"
MIGRATE_IDENTITY=""
MIGRATE_PROJECT_DIR=""
MIGRATE_SKIP_STORAGE=0

BLUE='\033[0;34m'; GREEN='\033[0;32m'; YELLOW='\033[1;33m'; RED='\033[0;31m'; NC='\033[0m'
info(){ printf '%b\n' "${BLUE}ℹ️  $*${NC}"; }
ok(){ printf '%b\n' "${GREEN}✅ $*${NC}"; }
warn(){ printf '%b\n' "${YELLOW}⚠️  $*${NC}"; }
err(){ printf '%b\n' "${RED}❌ $*${NC}"; }

show_build_header(){
  printf '\n%b\n' "${BLUE}🔨 AZEROTHCORE BUILD SYSTEM 🔨${NC}"
  printf '%b\n' "${BLUE}═══════════════════════════════════${NC}"
  printf '%b\n\n' "${BLUE}⚒️  Forging Your Custom Realm ⚒️${NC}"
}

usage(){
  cat <<EOF
Usage: $(basename "$0") [options]

Build AzerothCore with custom modules and create deployment-ready images.

Options:
  --yes, -y                    Auto-confirm all prompts
  --force                      Force rebuild even if no changes detected
  --source-path PATH           Custom source repository path
  --skip-source-setup          Skip automatic source repository setup
  --migrate-host HOST          Migrate built images to remote host after build
  --migrate-user USER          SSH username for remote migration
  --migrate-port PORT          SSH port for remote migration (default: 22)
  --migrate-identity PATH      SSH private key for remote migration
  --migrate-project-dir DIR    Remote project directory (default: auto-detect)
  --migrate-skip-storage       Skip storage sync during migration
  -h, --help                   Show this help

This script handles:
• Source repository preparation and updates
• Module staging and configuration
• AzerothCore compilation with enabled modules
• Docker image building and tagging
• Build state management
• Optional remote migration

Examples:
  ./build.sh                   Interactive build
  ./build.sh --yes             Auto-confirm build
  ./build.sh --force           Force rebuild regardless of state
  ./build.sh --yes \\
    --migrate-host prod-server \\
    --migrate-user deploy      Build and migrate to remote server
EOF
}

while [[ $# -gt 0 ]]; do
  case "$1" in
    --yes|-y) ASSUME_YES=1; shift;;
    --force) FORCE_REBUILD=1; shift;;
    --source-path) CUSTOM_SOURCE_PATH="$2"; shift 2;;
    --skip-source-setup) SKIP_SOURCE_SETUP=1; shift;;
    --migrate-host) MIGRATE_HOST="$2"; shift 2;;
    --migrate-user) MIGRATE_USER="$2"; shift 2;;
    --migrate-port) MIGRATE_PORT="$2"; shift 2;;
    --migrate-identity) MIGRATE_IDENTITY="$2"; shift 2;;
    --migrate-project-dir) MIGRATE_PROJECT_DIR="$2"; shift 2;;
    --migrate-skip-storage) MIGRATE_SKIP_STORAGE=1; shift;;
    -h|--help) usage; exit 0;;
    *) err "Unknown option: $1"; usage; exit 1;;
  esac
done

require_cmd(){
  command -v "$1" >/dev/null 2>&1 || { err "Missing required command: $1"; exit 1; }
}

require_cmd docker

# Validate migration parameters if any are provided
if [ -n "$MIGRATE_HOST" ] || [ -n "$MIGRATE_USER" ]; then
  if [ -z "$MIGRATE_HOST" ]; then
    err "Migration requires --migrate-host to be specified"
    exit 1
  fi
  if [ -z "$MIGRATE_USER" ]; then
    err "Migration requires --migrate-user to be specified"
    exit 1
  fi
  # Check that migrate-stack.sh exists
  if [ ! -f "$ROOT_DIR/scripts/migrate-stack.sh" ]; then
    err "Migration script not found: $ROOT_DIR/scripts/migrate-stack.sh"
    exit 1
  fi
fi

read_env(){
  local key="$1" default="${2:-}"
  local value=""
  if [ -f "$ENV_PATH" ]; then
    value="$(grep -E "^${key}=" "$ENV_PATH" 2>/dev/null | tail -n1 | cut -d'=' -f2- | tr -d '\r' | sed 's/[[:space:]]*#.*//' | sed 's/[[:space:]]*$//')"
  fi
  if [ -z "$value" ]; then
    value="$default"
  fi
  echo "$value"
}

# Module detection logic (extracted from deploy.sh)
COMPILE_MODULE_VARS=(
  MODULE_AOE_LOOT MODULE_LEARN_SPELLS MODULE_FIREWORKS MODULE_INDIVIDUAL_PROGRESSION MODULE_AHBOT MODULE_AUTOBALANCE
  MODULE_TRANSMOG MODULE_NPC_BUFFER MODULE_DYNAMIC_XP MODULE_SOLO_LFG MODULE_1V1_ARENA MODULE_PHASED_DUELS
  MODULE_BREAKING_NEWS MODULE_BOSS_ANNOUNCER MODULE_ACCOUNT_ACHIEVEMENTS MODULE_AUTO_REVIVE MODULE_GAIN_HONOR_GUARD
  MODULE_TIME_IS_TIME MODULE_POCKET_PORTAL MODULE_RANDOM_ENCHANTS MODULE_SOLOCRAFT MODULE_PVP_TITLES MODULE_NPC_BEASTMASTER
  MODULE_NPC_ENCHANTER MODULE_INSTANCE_RESET MODULE_LEVEL_GRANT MODULE_ARAC MODULE_ASSISTANT MODULE_REAGENT_BANK
  MODULE_CHALLENGE_MODES MODULE_OLLAMA_CHAT MODULE_PLAYER_BOT_LEVEL_BRACKETS MODULE_STATBOOSTER MODULE_DUNGEON_RESPAWN
  MODULE_SKELETON_MODULE MODULE_BG_SLAVERYVALLEY MODULE_AZEROTHSHARD MODULE_WORGOBLIN
)

requires_playerbot_source(){
  if [ "$(read_env MODULE_PLAYERBOTS "0")" = "1" ]; then
    return 0
  fi
  local var
  for var in "${COMPILE_MODULE_VARS[@]}"; do
    if [ "$(read_env "$var" "0")" = "1" ]; then
      return 0
    fi
  done
  return 1
}

ensure_source_repo(){
  local use_playerbot_source=0
  if requires_playerbot_source; then
    use_playerbot_source=1
  fi

  local local_root
  local_root="$(read_env STORAGE_PATH_LOCAL "./local-storage")"
  local_root="${local_root%/}"
  [ -z "$local_root" ] && local_root="."

  local default_source="${local_root}/source/azerothcore"
  if [ "$use_playerbot_source" = "1" ]; then
    default_source="${local_root}/source/azerothcore-playerbots"
  fi

  local src_path
  if [ -n "$CUSTOM_SOURCE_PATH" ]; then
    src_path="$CUSTOM_SOURCE_PATH"
  else
    src_path="$(read_env MODULES_REBUILD_SOURCE_PATH "$default_source")"
  fi

  if [[ "$src_path" != /* ]]; then
    src_path="$ROOT_DIR/$src_path"
  fi

  # Normalize path (extracted from deploy.sh)
  if command -v readlink >/dev/null 2>&1 && [[ -e "$src_path" || -e "$(dirname "$src_path")" ]]; then
    src_path="$(readlink -f "$src_path" 2>/dev/null || echo "$src_path")"
  else
    src_path="$(cd "$ROOT_DIR" && realpath -m "$src_path" 2>/dev/null || echo "$src_path")"
  fi
  src_path="${src_path//\/.\//\/}"

  if [ -d "$src_path/.git" ]; then
    echo "$src_path"
    return
  fi

  if [ "$SKIP_SOURCE_SETUP" = "1" ]; then
    err "Source repository not found at $src_path and --skip-source-setup specified"
    exit 1
  fi

  warn "AzerothCore source not found at $src_path; running setup-source.sh"
  if ! (cd "$ROOT_DIR" && ./scripts/setup-source.sh); then
    err "Failed to setup source repository"
    exit 1
  fi

  # Verify the source was actually created
  if [ ! -d "$src_path/.git" ]; then
    err "Source repository setup failed - no git directory at $src_path"
    exit 1
  fi

  echo "$src_path"
}

# Build state detection (extracted from setup.sh and deploy.sh)
modules_need_rebuild(){
  local storage_path
  storage_path="$(read_env STORAGE_PATH "./storage")"
  if [[ "$storage_path" != /* ]]; then
    storage_path="$ROOT_DIR/$storage_path"
  fi
  local sentinel="$storage_path/modules/.requires_rebuild"
  [[ -f "$sentinel" ]]
}

detect_rebuild_reasons(){
  local reasons=()

  # Check sentinel file
  if modules_need_rebuild; then
    reasons+=("Module changes detected (sentinel file present)")
  fi

  # Check if any C++ modules are enabled but modules-latest images don't exist
  local any_cxx_modules=0
  local var
  for var in "${COMPILE_MODULE_VARS[@]}"; do
    if [ "$(read_env "$var" "0")" = "1" ]; then
      any_cxx_modules=1
      break
    fi
  done

  if [ "$any_cxx_modules" = "1" ]; then
    local authserver_modules_image
    local worldserver_modules_image
    authserver_modules_image="$(read_env AC_AUTHSERVER_IMAGE_MODULES "uprightbass360/azerothcore-wotlk-playerbots:authserver-modules-latest")"
    worldserver_modules_image="$(read_env AC_WORLDSERVER_IMAGE_MODULES "uprightbass360/azerothcore-wotlk-playerbots:worldserver-modules-latest")"

    if ! docker image inspect "$authserver_modules_image" >/dev/null 2>&1; then
      reasons+=("C++ modules enabled but authserver modules image $authserver_modules_image is missing")
    fi
    if ! docker image inspect "$worldserver_modules_image" >/dev/null 2>&1; then
      reasons+=("C++ modules enabled but worldserver modules image $worldserver_modules_image is missing")
    fi
  fi

  printf '%s\n' "${reasons[@]}"
}

confirm_build(){
  local reasons=("$@")

  if [ ${#reasons[@]} -eq 0 ] && [ "$FORCE_REBUILD" = "0" ]; then
    info "No build required - all images are up to date"
    return 1  # No build needed
  fi

  # Skip duplicate output if called from deploy.sh (reasons already shown)
  local show_reasons=1
  if [ "$ASSUME_YES" -eq 1 ] && [ ${#reasons[@]} -gt 0 ]; then
    show_reasons=0  # deploy.sh already showed the reasons
  fi

  if [ "$show_reasons" -eq 1 ]; then
    echo
    if [ "$FORCE_REBUILD" = "1" ]; then
      warn "Force rebuild requested (--force flag)"
    elif [ ${#reasons[@]} -gt 0 ]; then
      warn "Build appears to be required:"
      local reason
      for reason in "${reasons[@]}"; do
        warn "  • $reason"
      done
    fi
    echo
  fi

  # Skip prompt if --yes flag is provided
  if [ "$ASSUME_YES" -eq 1 ]; then
    info "Auto-confirming build (--yes supplied)."
    return 0
  fi

  # Interactive prompt
  info "This will rebuild AzerothCore from source with your enabled modules."
  warn "⏱️  This process typically takes 15-45 minutes depending on your system."
  echo
  if [ -t 0 ]; then
    local reply
    read -r -p "Proceed with build? [y/N]: " reply
    reply="${reply:-n}"
    case "$reply" in
      [Yy]*)
        info "Build confirmed."
        return 0
        ;;
      *)
        info "Build cancelled."
        return 1
        ;;
    esac
  else
    warn "Standard input is not interactive; use --yes to auto-confirm."
    return 1
  fi
}

# Module staging logic (extracted from setup.sh)
sync_modules(){
  local storage_path
  storage_path="$(read_env STORAGE_PATH "./storage")"
  if [[ "$storage_path" != /* ]]; then
    storage_path="$ROOT_DIR/$storage_path"
  fi

  info "Synchronising modules (ac-modules container)"
  local project_name
  project_name="$(resolve_project_name)"
  docker compose --project-name "$project_name" -f "$ROOT_DIR/docker-compose.yml" --profile db --profile modules up ac-modules
  docker compose --project-name "$project_name" -f "$ROOT_DIR/docker-compose.yml" --profile db --profile modules down >/dev/null 2>&1 || true
}

resolve_project_name(){
  local raw_name="$(read_env COMPOSE_PROJECT_NAME "acore-compose")"
  local sanitized
  sanitized="$(echo "$raw_name" | tr '[:upper:]' '[:lower:]')"
  sanitized="${sanitized// /-}"
  sanitized="$(echo "$sanitized" | tr -cd 'a-z0-9_-')"
  if [[ -z "$sanitized" ]]; then
    sanitized="acore-compose"
  elif [[ ! "$sanitized" =~ ^[a-z0-9] ]]; then
    sanitized="ac${sanitized}"
  fi
  echo "$sanitized"
}

stage_modules(){
  local src_path="$1"
  local storage_path
  storage_path="$(read_env STORAGE_PATH "./storage")"
  if [[ "$storage_path" != /* ]]; then
    storage_path="$ROOT_DIR/$storage_path"
  fi

  info "Staging modules to source directory: $src_path/modules"

  # Verify source path exists
  if [ ! -d "$src_path" ]; then
    err "Source path does not exist: $src_path"
    return 1
  fi

  local local_modules_dir="${src_path}/modules"
  mkdir -p "$local_modules_dir"

  # Export module variables for the script
  local module_vars=(
    MODULE_PLAYERBOTS MODULE_AOE_LOOT MODULE_LEARN_SPELLS MODULE_FIREWORKS MODULE_INDIVIDUAL_PROGRESSION MODULE_AHBOT MODULE_AUTOBALANCE
    MODULE_TRANSMOG MODULE_NPC_BUFFER MODULE_DYNAMIC_XP MODULE_SOLO_LFG MODULE_1V1_ARENA MODULE_PHASED_DUELS
    MODULE_BREAKING_NEWS MODULE_BOSS_ANNOUNCER MODULE_ACCOUNT_ACHIEVEMENTS MODULE_AUTO_REVIVE MODULE_GAIN_HONOR_GUARD
    MODULE_ELUNA MODULE_TIME_IS_TIME MODULE_POCKET_PORTAL MODULE_RANDOM_ENCHANTS MODULE_SOLOCRAFT MODULE_PVP_TITLES
    MODULE_NPC_BEASTMASTER MODULE_NPC_ENCHANTER MODULE_INSTANCE_RESET MODULE_LEVEL_GRANT MODULE_ARAC MODULE_ASSISTANT
    MODULE_REAGENT_BANK MODULE_BLACK_MARKET_AUCTION_HOUSE MODULE_CHALLENGE_MODES MODULE_OLLAMA_CHAT
    MODULE_PLAYER_BOT_LEVEL_BRACKETS MODULE_STATBOOSTER MODULE_DUNGEON_RESPAWN MODULE_SKELETON_MODULE
    MODULE_BG_SLAVERYVALLEY MODULE_AZEROTHSHARD MODULE_WORGOBLIN MODULE_ELUNA_TS
  )

  local module_export_var
  for module_export_var in "${module_vars[@]}"; do
    export "$module_export_var"
  done

  local host_modules_dir="${storage_path}/modules"
  export MODULES_HOST_DIR="$host_modules_dir"

  # Prepare isolated git config for the module script
  local prev_git_config_global="${GIT_CONFIG_GLOBAL:-}"
  local git_temp_config=""
  if command -v mktemp >/dev/null 2>&1; then
    if ! git_temp_config="$(mktemp)"; then
      git_temp_config=""
    fi
  fi
  if [ -z "$git_temp_config" ]; then
    git_temp_config="$local_modules_dir/.gitconfig.tmp"
    : > "$git_temp_config"
  fi
  export GIT_CONFIG_GLOBAL="$git_temp_config"

  # Run module staging script in local modules directory
  export MODULES_LOCAL_RUN=1
  if [ -n "$host_modules_dir" ]; then
    mkdir -p "$host_modules_dir"
    rm -f "$host_modules_dir/.modules_state" "$host_modules_dir/.requires_rebuild" 2>/dev/null || true
  fi

  if (cd "$local_modules_dir" && bash "$ROOT_DIR/scripts/manage-modules.sh"); then
    ok "Module repositories staged to $local_modules_dir"
    if [ -n "$host_modules_dir" ]; then
      if [ -f "$local_modules_dir/.modules_state" ]; then
        cp "$local_modules_dir/.modules_state" "$host_modules_dir/.modules_state" 2>/dev/null || true
      fi
    fi
  else
    warn "Module staging encountered issues, but continuing with build"
  fi

  # Cleanup
  export GIT_CONFIG_GLOBAL="$prev_git_config_global"
  unset MODULES_LOCAL_RUN
  unset MODULES_HOST_DIR
  [ -n "$git_temp_config" ] && [ -f "$git_temp_config" ] && rm -f "$git_temp_config"
}

# Build execution (extracted from setup.sh)
execute_build(){
  local src_path="$1"

  # Verify source path exists
  if [ ! -d "$src_path" ]; then
    err "Source path does not exist: $src_path"
    return 1
  fi

  local compose_file="$src_path/docker-compose.yml"
  if [ ! -f "$compose_file" ]; then
    err "Source docker-compose.yml missing at $compose_file"
    return 1
  fi

  info "Building AzerothCore with modules (this may take a while)"
  docker compose -f "$compose_file" down --remove-orphans >/dev/null 2>&1 || true

  if (cd "$ROOT_DIR" && ./scripts/rebuild-with-modules.sh --yes --source "$src_path"); then
    ok "Source build completed"
  else
    err "Source build failed"
    return 1
  fi

  docker compose -f "$compose_file" down --remove-orphans >/dev/null 2>&1 || true
}

# Image tagging (extracted from setup.sh and deploy.sh)
tag_module_images(){
  local source_auth
  local source_world
  local target_auth
  local target_world

  source_auth="$(read_env AC_AUTHSERVER_IMAGE_PLAYERBOTS "uprightbass360/azerothcore-wotlk-playerbots:authserver-Playerbot")"
  source_world="$(read_env AC_WORLDSERVER_IMAGE_PLAYERBOTS "uprightbass360/azerothcore-wotlk-playerbots:worldserver-Playerbot")"
  target_auth="$(read_env AC_AUTHSERVER_IMAGE_MODULES "uprightbass360/azerothcore-wotlk-playerbots:authserver-modules-latest")"
  target_world="$(read_env AC_WORLDSERVER_IMAGE_MODULES "uprightbass360/azerothcore-wotlk-playerbots:worldserver-modules-latest")"

  if docker image inspect "$source_auth" >/dev/null 2>&1; then
    docker tag "$source_auth" "$target_auth"
    ok "Tagged $target_auth from $source_auth"
  else
    warn "Source authserver image $source_auth not found; skipping modules tag"
  fi

  if docker image inspect "$source_world" >/dev/null 2>&1; then
    docker tag "$source_world" "$target_world"
    ok "Tagged $target_world from $source_world"
  else
    warn "Source worldserver image $source_world not found; skipping modules tag"
  fi
}

run_migration(){
  if [ -z "$MIGRATE_HOST" ] || [ -z "$MIGRATE_USER" ]; then
    return 0  # No migration requested
  fi

  info "Starting remote migration to $MIGRATE_USER@$MIGRATE_HOST"

  # Build migrate-stack.sh arguments
  local migrate_args=(
    --host "$MIGRATE_HOST"
    --user "$MIGRATE_USER"
  )

  if [ "$MIGRATE_PORT" != "22" ]; then
    migrate_args+=(--port "$MIGRATE_PORT")
  fi

  if [ -n "$MIGRATE_IDENTITY" ]; then
    migrate_args+=(--identity "$MIGRATE_IDENTITY")
  fi

  if [ -n "$MIGRATE_PROJECT_DIR" ]; then
    migrate_args+=(--project-dir "$MIGRATE_PROJECT_DIR")
  fi

  if [ "$MIGRATE_SKIP_STORAGE" = "1" ]; then
    migrate_args+=(--skip-storage)
  fi

  if [ "$ASSUME_YES" = "1" ]; then
    migrate_args+=(--yes)
  fi

  if (cd "$ROOT_DIR" && ./scripts/migrate-stack.sh "${migrate_args[@]}"); then
    ok "Migration completed successfully"
    echo
    info "Remote deployment ready! Run on $MIGRATE_HOST:"
    printf '  %bcd %s && ./deploy.sh --no-watch%b\n' "$YELLOW" "${MIGRATE_PROJECT_DIR:-~/acore-compose}" "$NC"
  else
    warn "Migration failed, but build completed successfully"
    return 1
  fi
}

show_build_complete(){
  printf '\n%b\n' "${GREEN}🔨 Build Complete! 🔨${NC}"
  printf '%b\n' "${GREEN}⚒️  Your custom AzerothCore images are ready${NC}"
  if [ -n "$MIGRATE_HOST" ]; then
    printf '%b\n\n' "${GREEN}🌐 Remote migration completed${NC}"
  else
    printf '%b\n\n' "${GREEN}🚀 Ready for deployment with ./deploy.sh${NC}"
  fi
}

main(){
  show_build_header

  local src_dir
  local rebuild_reasons

  info "Step 1/7: Setting up source repository"
  src_dir="$(ensure_source_repo)"

  info "Step 2/7: Detecting build requirements"
  readarray -t rebuild_reasons < <(detect_rebuild_reasons)

  if ! confirm_build "${rebuild_reasons[@]}"; then
    info "Build cancelled or not required."
    exit 0
  fi

  info "Step 3/7: Syncing modules to container storage"
  sync_modules

  info "Step 4/7: Staging modules to source directory"
  stage_modules "$src_dir"

  info "Step 5/7: Building AzerothCore with modules"
  execute_build "$src_dir"

  info "Step 6/7: Tagging images for deployment"
  tag_module_images

  # Clear build sentinel after successful build
  local storage_path
  storage_path="$(read_env STORAGE_PATH "./storage")"
  if [[ "$storage_path" != /* ]]; then
    storage_path="$ROOT_DIR/$storage_path"
  fi
  local sentinel="$storage_path/modules/.requires_rebuild"
  rm -f "$sentinel" 2>/dev/null || true

  # Run remote migration if requested
  if [ -n "$MIGRATE_HOST" ]; then
    echo
    info "Step 7/7: Migrating images to remote host"
    run_migration
  fi

  show_build_complete
}

main "$@"