#!/usr/bin/env bash
# ═══════════════════════════════════════════════════════════════════
# 个人资料库 — 一键更新脚本
# 支持镜像来源：Gitea 镜像仓库（拉取）/ 本地源码（重新构建）
# 失败时自动回滚至上一版本
#
# 用法：bash scripts/update.sh [--yes] [--tag <镜像标签>]
#   --yes        跳过确认提示
#   --tag <tag>  指定目标镜像标签（默认: latest）
# ═══════════════════════════════════════════════════════════════════
set -euo pipefail
IFS=$'\n\t'

# ── 脚本自身位置 & 项目根目录 ─────────────────────────────────────
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
PROJECT_DIR="$(dirname "$SCRIPT_DIR")"
STATE_FILE="$PROJECT_DIR/.deploy-state"
LOG_FILE="/tmp/resource-library-update-$(date +%Y%m%d%H%M%S).log"

# ── 颜色 & 输出 ──────────────────────────────────────────────────
RED='\033[0;31m'; GREEN='\033[0;32m'; YELLOW='\033[1;33m'
BLUE='\033[0;34m'; CYAN='\033[0;36m'; BOLD='\033[1m'; NC='\033[0m'

log()     { echo -e "$(date '+%H:%M:%S') $*" | tee -a "$LOG_FILE"; }
info()    { echo -e "${CYAN}[INFO]${NC}  $*" | tee -a "$LOG_FILE"; }
ok()      { echo -e "${GREEN}[ OK ]${NC}  $*" | tee -a "$LOG_FILE"; }
warn()    { echo -e "${YELLOW}[WARN]${NC}  $*" | tee -a "$LOG_FILE"; }
err()     { echo -e "${RED}[ERR ]${NC}  $*" | tee -a "$LOG_FILE" >&2; }
die()     { err "$*"; exit 1; }
section() { echo -e "\n${BOLD}${BLUE}── $* ─────────────────────────────────────${NC}" | tee -a "$LOG_FILE"; }

banner() {
cat << 'EOF'

  ╔═══════════════════════════════════════════╗
  ║         个人资料库  一键更新脚本          ║
  ║   Personal Resource Library  Updater      ║
  ╚═══════════════════════════════════════════╝

EOF
}

# ── 参数解析 ──────────────────────────────────────────────────────
AUTO_YES="no"
TARGET_TAG="latest"

while [ $# -gt 0 ]; do
    case "$1" in
        -y|--yes)   AUTO_YES="yes" ;;
        --tag)      shift; TARGET_TAG="${1:-latest}" ;;
        -h|--help)
            echo "用法: $0 [--yes] [--tag <镜像标签>]"
            echo "  --yes        跳过确认"
            echo "  --tag <tag>  指定镜像标签（默认: latest）"
            exit 0 ;;
        *) warn "未知参数: $1" ;;
    esac
    shift
done

# ── 工具函数 ──────────────────────────────────────────────────────
command_exists() { command -v "$1" &>/dev/null; }

confirm() {
    [ "$AUTO_YES" = "yes" ] && return 0
    echo -e "${YELLOW}[?]${NC}    $* [y/N]: "
    read -r ans
    echo "$ans" | grep -qiE "^y(es)?$"
}

# ── 读取部署状态 ──────────────────────────────────────────────────
load_state() {
    section "读取部署状态"

    [ -f "$STATE_FILE" ] || die "未找到 .deploy-state 文件，请先运行 deploy.sh"

    # shellcheck disable=SC1090
    . "$STATE_FILE"

    # 必须存在的字段
    : "${DEPLOY_MODE:?STATE 缺少 DEPLOY_MODE}"
    : "${COMPOSE_FILE:?STATE 缺少 COMPOSE_FILE}"
    : "${ENV_FILE:?STATE 缺少 ENV_FILE}"
    : "${IMAGE_SOURCE:?STATE 缺少 IMAGE_SOURCE}"

    local env_path="$PROJECT_DIR/$ENV_FILE"
    [ -f "$env_path" ] || die "env 文件不存在: $env_path"

    ok "部署模式:  $DEPLOY_MODE"
    ok "镜像来源:  $IMAGE_SOURCE"
    ok "Compose:   $COMPOSE_FILE"
    ok "上次部署:  ${DEPLOYED_AT:-未知}"
}

# ── 检测 Docker Compose 命令 ──────────────────────────────────────
detect_compose() {
    if docker compose version &>/dev/null 2>&1; then
        COMPOSE_CMD="docker compose"
    elif command_exists docker-compose; then
        COMPOSE_CMD="docker-compose"
    else
        die "未找到 docker compose / docker-compose，请先运行 deploy.sh"
    fi
    ok "Compose: $COMPOSE_CMD"
}

# ── 获取当前运行镜像的摘要 ────────────────────────────────────────
get_current_digest() {
    local container_name="${1:-resource_library_app}"
    docker inspect "$container_name" \
        --format='{{index .Config.Image}}:{{.Image}}' 2>/dev/null ||
    echo "unknown"
}

# ── 拉取最新镜像 ──────────────────────────────────────────────────
pull_image() {
    section "拉取最新镜像"
    local image="${REGISTRY_IMAGE}:${TARGET_TAG}"

    info "目标镜像: $image"
    OLD_DIGEST=$(docker inspect "$image" --format='{{.Id}}' 2>/dev/null || echo "none")
    info "当前本地摘要: ${OLD_DIGEST:0:19}…"

    info "拉取镜像…"
    if ! docker pull "$image" 2>&1 | tee -a "$LOG_FILE"; then
        err "镜像拉取失败"
        return 1
    fi

    NEW_DIGEST=$(docker inspect "$image" --format='{{.Id}}' 2>/dev/null || echo "none")
    info "最新远端摘要: ${NEW_DIGEST:0:19}…"

    if [ "$OLD_DIGEST" = "$NEW_DIGEST" ] && [ "$OLD_DIGEST" != "none" ]; then
        warn "镜像未变更（摘要相同），无需更新"
        if ! confirm "仍要重启服务吗？"; then
            ok "跳过更新"
            exit 0
        fi
    else
        ok "检测到新版本镜像"
    fi
}

# ── 本地重新构建镜像 ──────────────────────────────────────────────
build_image() {
    section "本地重新构建镜像"
    cd "$PROJECT_DIR"

    # 尝试拉取最新代码
    if command_exists git && [ -d .git ]; then
        info "拉取最新代码…"
        local branch
        branch=$(git rev-parse --abbrev-ref HEAD 2>/dev/null || echo "unknown")
        if git pull --ff-only 2>&1 | tee -a "$LOG_FILE"; then
            ok "代码已更新（分支: $branch）"
        else
            warn "git pull 失败，使用当前代码构建"
        fi
    fi

    info "重新构建镜像…"
    docker build -t resource-library:latest . 2>&1 | tee -a "$LOG_FILE"
    ok "镜像构建完成"
}

# ── 备份当前容器镜像标签（用于回滚）─────────────────────────────
backup_current_image() {
    section "备份当前镜像"

    local rollback_tag
    rollback_tag="rollback-$(date +%Y%m%d%H%M%S)"
    ROLLBACK_TAG="$rollback_tag"

    local current_image
    if [ "$IMAGE_SOURCE" = "registry" ]; then
        current_image="${REGISTRY_IMAGE}:${TARGET_TAG}"
    else
        current_image="resource-library:latest"
    fi

    if docker image inspect "$current_image" &>/dev/null; then
        local target_tag
        if [ "$IMAGE_SOURCE" = "registry" ]; then
            target_tag="${REGISTRY_IMAGE}:${rollback_tag}"
        else
            target_tag="resource-library:${rollback_tag}"
        fi
        docker tag "$current_image" "$target_tag"
        ok "备份标签: $target_tag"
        ROLLBACK_IMAGE="$target_tag"
    else
        warn "当前镜像不存在，跳过备份（首次更新？）"
        ROLLBACK_IMAGE=""
    fi
}

# ── 滚动更新服务 ──────────────────────────────────────────────────
rolling_update() {
    section "滚动更新服务"
    cd "$PROJECT_DIR"

    local compose_args=(--env-file "$ENV_FILE" -f "$COMPOSE_FILE")
    [ "${USE_NGINX:-no}" = "yes" ] && compose_args+=(--profile nginx)

    info "拉起新容器…"
    $COMPOSE_CMD "${compose_args[@]}" up -d --remove-orphans 2>&1 | tee -a "$LOG_FILE"
    ok "新容器已启动"
}

# ── 健康检查 ──────────────────────────────────────────────────────
health_check() {
    section "健康检查"
    local max_wait=90 elapsed=0 interval=5
    local url="http://localhost:${APP_PORT:-5000}/auth/login"

    info "等待服务就绪（最长 ${max_wait}s）…"
    while [ "$elapsed" -lt "$max_wait" ]; do
        if curl -fsSL --max-time 5 "$url" > /dev/null 2>&1; then
            ok "服务健康！（${elapsed}s）"
            return 0
        fi
        printf '.'
        sleep "$interval"
        elapsed=$((elapsed + interval))
    done
    echo
    err "健康检查超时"
    return 1
}

# ── 自动回滚 ──────────────────────────────────────────────────────
rollback() {
    section "⚠️  触发自动回滚"

    if [ -z "${ROLLBACK_IMAGE:-}" ]; then
        err "无备份镜像，无法回滚，请手动排查"
        exit 1
    fi

    warn "正在恢复到备份版本: $ROLLBACK_IMAGE"
    cd "$PROJECT_DIR"

    # 将备份镜像还原为目标标签
    if [ "$IMAGE_SOURCE" = "registry" ]; then
        docker tag "$ROLLBACK_IMAGE" "${REGISTRY_IMAGE}:${TARGET_TAG}"
    else
        docker tag "$ROLLBACK_IMAGE" "resource-library:latest"
    fi

    local compose_args=(--env-file "$ENV_FILE" -f "$COMPOSE_FILE")
    [ "${USE_NGINX:-no}" = "yes" ] && compose_args+=(--profile nginx)

    $COMPOSE_CMD "${compose_args[@]}" up -d 2>&1 | tee -a "$LOG_FILE"

    # 等待回滚后服务就绪
    local rb_wait=60 elapsed=0
    while [ "$elapsed" -lt "$rb_wait" ]; do
        if curl -fsSL --max-time 5 "http://localhost:${APP_PORT:-5000}/auth/login" > /dev/null 2>&1; then
            ok "回滚成功，服务已恢复（${elapsed}s）"
            echo
            err "本次更新失败，已回滚至备份版本: $ROLLBACK_IMAGE"
            err "更新日志: $LOG_FILE"
            exit 1
        fi
        sleep 5
        elapsed=$((elapsed + 5))
    done

    die "回滚后服务仍不健康，请手动检查: $COMPOSE_CMD ${compose_args[*]} logs"
}

# ── 清理旧回滚标签（保留最近 3 个）──────────────────────────────
cleanup_old_backups() {
    section "清理旧备份镜像"
    local prefix
    if [ "$IMAGE_SOURCE" = "registry" ]; then
        prefix="${REGISTRY_IMAGE}:rollback-"
    else
        prefix="resource-library:rollback-"
    fi

    # 列出所有 rollback-* 标签，按时间排序，保留最新 3 个
    local tags=()
    while IFS= read -r tag; do
        tags+=("$tag")
    done < <(docker images --format '{{.Repository}}:{{.Tag}}' | grep "^${prefix}" | sort -r)

    local keep=3
    if [ "${#tags[@]}" -gt "$keep" ]; then
        local to_delete=("${tags[@]:$keep}")
        for tag in "${to_delete[@]}"; do
            info "删除旧备份镜像: $tag"
            docker rmi "$tag" 2>/dev/null || true
        done
        ok "已清理 ${#to_delete[@]} 个旧备份"
    else
        ok "备份数量未超限（${#tags[@]}/${keep}），无需清理"
    fi
}

# ── 打印更新结果 ──────────────────────────────────────────────────
print_success() {
    local local_ip
    local_ip=$(hostname -I 2>/dev/null | awk '{print $1}') || local_ip="<服务器IP>"

    echo
    echo -e "${GREEN}${BOLD}═══════════════════════════════════════════════${NC}"
    echo -e "${GREEN}${BOLD}  🚀  更新成功！                              ${NC}"
    echo -e "${GREEN}${BOLD}═══════════════════════════════════════════════${NC}"
    echo
    echo -e "  访问地址:  ${CYAN}http://${local_ip}:${APP_PORT:-5000}${NC}"
    echo
    if [ -n "${ROLLBACK_IMAGE:-}" ]; then
        echo -e "  回滚备份:  ${YELLOW}$ROLLBACK_IMAGE${NC}"
        echo -e "  手动回滚:  ${BLUE}docker tag $ROLLBACK_IMAGE ${REGISTRY_IMAGE:-resource-library}:latest${NC}"
        echo -e "             ${BLUE}$COMPOSE_CMD -f $COMPOSE_FILE up -d${NC}"
    fi
    echo
    echo -e "  查看日志:  ${BLUE}$COMPOSE_CMD -f $COMPOSE_FILE logs -f${NC}"
    echo -e "  更新日志:  $LOG_FILE"
    echo -e "${GREEN}${BOLD}═══════════════════════════════════════════════${NC}"
    echo
}

# ── 主流程 ────────────────────────────────────────────────────────
main() {
    banner
    log "更新日志: $LOG_FILE"

    load_state
    detect_compose

    # 显示当前状态
    section "当前运行状态"
    $COMPOSE_CMD -f "$COMPOSE_FILE" ps 2>/dev/null | tee -a "$LOG_FILE" || true

    # 确认更新
    confirm "确认执行更新？" || { info "已取消"; exit 0; }

    backup_current_image

    # 根据镜像来源更新
    if [ "$IMAGE_SOURCE" = "registry" ]; then
        pull_image || { rollback; }
    else
        build_image
    fi

    rolling_update

    if ! health_check; then
        rollback
    fi

    # 更新状态文件中的时间戳
    sed -i "s/^DEPLOYED_AT=.*/DEPLOYED_AT=$(date -u '+%Y-%m-%dT%H:%M:%SZ')/" \
        "$STATE_FILE" 2>/dev/null || true

    cleanup_old_backups
    print_success
}

main "$@"