#!/bin/sh

set -eu

WEBAPP_ROOT="/home/webapp"
ENV_ROOT="$WEBAPP_ROOT/env"
APP_ROOT="$WEBAPP_ROOT/loan-pricing"
JAVA_HOME="$ENV_ROOT/java"
NGINX_HOME="$ENV_ROOT/nginx"
NGINX_CONF="$NGINX_HOME/conf/nginx.conf"
BACKEND_DIR="$APP_ROOT/backend"
FRONTEND_DIR="$APP_ROOT/frontend"
FRONTEND_DIST_DIR="$FRONTEND_DIR/dist"
BACKUP_DIR="$APP_ROOT/backup"
LOG_DIR="$APP_ROOT/logs"
RUN_DIR="$APP_ROOT/run"
TMP_DIR="$APP_ROOT/tmp"
BACKEND_JAR="$BACKEND_DIR/ruoyi-admin.jar"
FRONTEND_PORT=63311
JAVA_RESTART_SCRIPT="$WEBAPP_ROOT/restart_java.sh"

timestamp() {
    date "+%Y-%m-%d %H:%M:%S"
}

log_info() {
    printf '[%s] %s\n' "$(timestamp)" "$1"
}

log_error() {
    printf '[%s] %s\n' "$(timestamp)" "$1" >&2
}

usage() {
    cat <<'EOF'
用法:
  ./bin/prod/deploy_release.sh <发布压缩包路径>
EOF
}

require_root() {
    if [ "$(id -u)" -ne 0 ]; then
        log_error "请使用 root 用户执行部署脚本"
        exit 1
    fi
}

require_command() {
    if ! command -v "$1" >/dev/null 2>&1; then
        log_error "缺少命令: $1"
        exit 1
    fi
}

ensure_runtime_dirs() {
    mkdir -p "$BACKEND_DIR" "$FRONTEND_DIR" "$BACKUP_DIR" "$LOG_DIR" "$RUN_DIR" "$TMP_DIR"
}

cleanup() {
    if [ -n "${WORK_DIR:-}" ] && [ -d "$WORK_DIR" ]; then
        rm -rf "$WORK_DIR"
    fi
}

extract_release_package() {
    release_archive="$1"
    release_extract_dir="$2"

    mkdir -p "$release_extract_dir"

    case "$release_archive" in
        *.zip)
            unzip -oq "$release_archive" -d "$release_extract_dir"
            ;;
        *.tar.gz|*.tgz)
            tar -xzf "$release_archive" -C "$release_extract_dir"
            ;;
        *.tar)
            tar -xf "$release_archive" -C "$release_extract_dir"
            ;;
        *)
            log_error "不支持的发布包格式: $release_archive"
            exit 1
            ;;
    esac
}

assert_single_file() {
    search_dir="$1"
    file_name="$2"
    description="$3"
    count=$(find "$search_dir" -type f -name "$file_name" | wc -l | tr -d ' ')

    if [ "$count" -ne 1 ]; then
        log_error "$description 数量不正确，期望 1 个，实际 $count 个"
        exit 1
    fi

    find "$search_dir" -type f -name "$file_name" | head -n 1
}

assert_single_jar() {
    search_dir="$1"
    count=$(find "$search_dir" -type f -name '*.jar' | wc -l | tr -d ' ')

    if [ "$count" -ne 1 ]; then
        log_error "后端 jar 数量不正确，期望 1 个，实际 $count 个"
        exit 1
    fi

    find "$search_dir" -type f -name '*.jar' | head -n 1
}

backup_current_release() {
    backup_stamp=$(date "+%Y%m%d%H%M%S")
    CURRENT_BACKUP_DIR="$BACKUP_DIR/$backup_stamp"

    mkdir -p "$CURRENT_BACKUP_DIR/backend" "$CURRENT_BACKUP_DIR/frontend"

    if [ -f "$BACKEND_JAR" ]; then
        cp -a "$BACKEND_JAR" "$CURRENT_BACKUP_DIR/backend/"
    fi

    if [ -d "$FRONTEND_DIST_DIR" ]; then
        cp -a "$FRONTEND_DIST_DIR" "$CURRENT_BACKUP_DIR/frontend/"
    fi

    log_info "旧版本已备份到: $CURRENT_BACKUP_DIR"
}

deploy_backend() {
    source_jar="$1"

    rm -f "$BACKEND_DIR"/*.jar
    cp "$source_jar" "$BACKEND_JAR"
}

resolve_frontend_source_dir() {
    unzip_dir="$1"

    if [ -f "$unzip_dir/index.html" ]; then
        printf '%s\n' "$unzip_dir"
        return 0
    fi

    if [ -f "$unzip_dir/dist/index.html" ]; then
        printf '%s\n' "$unzip_dir/dist"
        return 0
    fi

    candidate=$(find "$unzip_dir" -type f -name 'index.html' | head -n 1)
    if [ -z "${candidate:-}" ]; then
        log_error "dist.zip 解压后未找到 index.html"
        exit 1
    fi

    dirname "$candidate"
}

deploy_frontend() {
    dist_zip="$1"
    dist_unpack_dir="$WORK_DIR/frontend"

    mkdir -p "$dist_unpack_dir"
    unzip -oq "$dist_zip" -d "$dist_unpack_dir"

    frontend_source_dir=$(resolve_frontend_source_dir "$dist_unpack_dir")
    rm -rf "$FRONTEND_DIST_DIR"
    mkdir -p "$FRONTEND_DIST_DIR"
    cp -a "$frontend_source_dir"/. "$FRONTEND_DIST_DIR"/
}

reload_nginx() {
    nginx_pid_file="$RUN_DIR/nginx.pid"

    "$NGINX_HOME/sbin/nginx" -t -c "$NGINX_CONF"

    if [ -f "$nginx_pid_file" ]; then
        nginx_pid=$(cat "$nginx_pid_file" 2>/dev/null || true)
        if [ -n "${nginx_pid:-}" ] && kill -0 "$nginx_pid" 2>/dev/null; then
            "$NGINX_HOME/sbin/nginx" -c "$NGINX_CONF" -s reload
            log_info "Nginx 已重载，前端端口: $FRONTEND_PORT"
            return 0
        fi
    fi

    "$NGINX_HOME/sbin/nginx" -c "$NGINX_CONF"
    log_info "Nginx 已启动，前端端口: $FRONTEND_PORT"
}

main() {
    if [ "$#" -ne 1 ]; then
        usage
        exit 1
    fi

    require_root
    require_command tar
    require_command unzip
    require_command find

    release_archive="$1"
    if [ ! -f "$release_archive" ]; then
        log_error "发布压缩包不存在: $release_archive"
        exit 1
    fi

    if [ ! -x "$JAVA_HOME/bin/java" ]; then
        log_error "未检测到 Java，请先执行 ./bin/prod/install_env.sh"
        exit 1
    fi

    if [ ! -x "$NGINX_HOME/sbin/nginx" ]; then
        log_error "未检测到 Nginx，请先执行 ./bin/prod/install_env.sh"
        exit 1
    fi

    if [ ! -x "$JAVA_RESTART_SCRIPT" ]; then
        log_error "未检测到 Java 重启脚本: $JAVA_RESTART_SCRIPT"
        exit 1
    fi

    ensure_runtime_dirs
    WORK_DIR=$(mktemp -d "$TMP_DIR/release.XXXXXX")
    trap cleanup EXIT INT TERM

    extract_release_package "$release_archive" "$WORK_DIR/package"

    backend_jar_source=$(assert_single_jar "$WORK_DIR/package")
    frontend_dist_source=$(assert_single_file "$WORK_DIR/package" 'dist.zip' '前端 dist.zip')

    backup_current_release
    "$JAVA_RESTART_SCRIPT" stop
    deploy_backend "$backend_jar_source"
    deploy_frontend "$frontend_dist_source"
    "$JAVA_RESTART_SCRIPT" start
    reload_nginx

    log_info "部署完成"
    log_info "后端 jar: $BACKEND_JAR"
    log_info "前端目录: $FRONTEND_DIST_DIR"
    log_info "备份目录: $CURRENT_BACKUP_DIR"
}

main "$@"