name: query_mail_messages
desc: 通过 iAs 邮件 HTTP API 查询邮件列表或搜索邮件，支持关键词、邮箱目录、来源和分页过滤。返回邮件总数、分页信息和当前页邮件 JSON 列表。
params:
    - name: base_url
      type: string
      required: false
      default: "http://127.0.0.1:9003"
      description: iAs HTTP 服务地址，默认 http://127.0.0.1:9003；如果服务绑定了其他地址可覆盖。
    - name: q
      type: string
      required: false
      default: ""
      description: 搜索关键词，会匹配发件人、主题、摘要、正文和 Message-ID。
    - name: mailbox
      type: string
      required: false
      default: ""
      description: 邮箱目录过滤，例如 INBOX；为空则不过滤。
    - name: source_key
      type: string
      required: false
      default: ""
      description: 邮件来源过滤；为空则不过滤。
    - name: page
      type: integer
      required: false
      default: "1"
      description: 页码，默认 1。
    - name: per_page
      type: integer
      required: false
      default: "10"
      description: 每页数量，默认 10，接口最大 100。
steps:
    - url: ${param:base_url}/v1/mail/messages
      method: GET
      query:
          - [q, "${param:q}"]
          - [mailbox, "${param:mailbox}"]
          - [source_key, "${param:source_key}"]
          - [page, "${param:page}"]
          - [per_page, "${param:per_page}"]
      timeout: 20
      var:
          - name: success
            extract: success
            default: "false"
          - name: page
            extract: page
            default: "1"
          - name: per_page
            extract: per_page
            default: "0"
          - name: total
            extract: total
            default: "0"
          - name: messages
            extract: messages
            default: "[]"
      result: |
          邮件查询 success=${step0:success}, page=${step0:page}, per_page=${step0:per_page}, total=${step0:total}
          messages=${step0:messages}