"""企业微信模板卡片构建模块。

将契约层 ``RichMessage`` DTO 映射为企业微信模板卡片 JSON，支持 5 种子类型：
- ``text_notice``: 文本通知型
- ``news_notice``: 图文展示型
- ``button_interaction``: 按钮交互型
- ``vote_interaction``: 投票选择型
- ``multiple_interaction``: 多项选择型

并提供降级 Markdown 文本的构建能力。仅依赖契约层 DTO 与标准库。
"""

from __future__ import annotations

from typing import Any

from yuxi.channels.contract.dtos.outbound import RichMessage


def build_template_card_from_rich_message(rich_message: RichMessage) -> dict[str, Any]:
    """将 ``RichMessage`` 映射为企业微信模板卡片 JSON。

    映射规则：
        - 有 ``buttons`` → ``button_interaction`` 类型
        - 有 ``checkboxes`` → ``multiple_interaction`` 类型
        - 有 ``selects`` 且无 buttons → ``vote_interaction`` 类型
        - 有 ``image_url`` 且无交互元素 → ``news_notice`` 类型
        - 默认 → ``text_notice`` 类型

    Returns:
        ``{"msgtype": "template_card", "template_card": {...}}`` 格式 dict。
    """
    card_type = _infer_card_type(rich_message)
    card: dict[str, Any] = {
        "card_type": card_type,
    }

    if rich_message.title:
        card["main_title"] = {"title": rich_message.title}

    if rich_message.text:
        card.setdefault("main_title", {})["desc"] = rich_message.text

    if rich_message.description:
        card["subtitle"] = rich_message.description

    if rich_message.image_url and card_type == "news_notice":
        card["image_url"] = rich_message.image_url

    if card_type == "button_interaction":
        card["button_list"] = _build_button_list(rich_message.buttons)

    if card_type == "vote_interaction":
        # 企业微信 vote_interaction 卡片使用 option_list 字段（非 checkboxes，
        # 与 multiple_interaction 区分），否则 API 拒绝
        card["option_list"] = _build_vote_options(rich_message.selects)

    if card_type == "multiple_interaction":
        card["checkboxes"] = _build_multiple_options(rich_message.checkboxes)

    return {"msgtype": "template_card", "template_card": card}


def build_text_notice_card(
    title: str,
    description: str,
    *,
    url: str | None = None,
) -> dict[str, Any]:
    """构建文本通知型模板卡片。

    用于流式输出首块占位卡片（决策 4）。
    """
    card: dict[str, Any] = {
        "card_type": "text_notice",
        "main_title": {"title": title, "desc": description},
    }
    if url:
        card["url"] = url
    return {"msgtype": "template_card", "template_card": card}


def build_markdown_message(content: str) -> dict[str, Any]:
    """构建 Markdown 消息。

    企业微信 Markdown 消息格式：``{"msgtype": "markdown", "markdown": {"content": "..."}}``。
    """
    return {"msgtype": "markdown", "markdown": {"content": content}}


def build_text_message(content: str) -> dict[str, Any]:
    """构建文本消息。

    企业微信文本消息格式：``{"msgtype": "text", "text": {"content": "..."}}``。
    """
    return {"msgtype": "text", "text": {"content": content}}


def build_image_message(media_id: str) -> dict[str, Any]:
    """构建图片消息。"""
    return {"msgtype": "image", "image": {"media_id": media_id}}


def build_video_message(media_id: str, thumb_media_id: str = "") -> dict[str, Any]:
    """构建视频消息。"""
    return {"msgtype": "video", "video": {"media_id": media_id, "thumb_media_id": thumb_media_id}}


def build_voice_message(media_id: str) -> dict[str, Any]:
    """构建语音消息。"""
    return {"msgtype": "voice", "voice": {"media_id": media_id}}


def build_file_message(media_id: str) -> dict[str, Any]:
    """构建文件消息。"""
    return {"msgtype": "file", "file": {"media_id": media_id}}


def degrade_to_markdown(rich_message: RichMessage) -> str:
    """将 ``RichMessage`` 降级为 Markdown 文本，空字段跳过。

    标题用 ``# `` 前缀，按钮用 ``- [label](value)`` 列表。
    """
    lines: list[str] = []
    if rich_message.title:
        lines.append(f"# {rich_message.title}")
    if rich_message.text:
        lines.append(rich_message.text)
    if rich_message.description:
        lines.append(rich_message.description)
    if rich_message.buttons:
        for btn in rich_message.buttons:
            target = btn.value or btn.action
            lines.append(f"- [{btn.label}]({target})")
    return "\n".join(lines)


def _infer_card_type(rich_message: RichMessage) -> str:
    """根据 RichMessage 字段推断模板卡片子类型。"""
    if rich_message.buttons:
        return "button_interaction"
    if rich_message.checkboxes:
        return "multiple_interaction"
    if rich_message.selects:
        return "vote_interaction"
    if rich_message.image_url:
        return "news_notice"
    return "text_notice"


def _build_button_list(buttons: tuple[Any, ...]) -> list[dict[str, Any]]:
    """构建按钮交互型 button_list。"""
    result: list[dict[str, Any]] = []
    for btn in buttons:
        item: dict[str, Any] = {"text": btn.label, "style": 1}
        if btn.value is not None:
            item["key"] = btn.value
        elif btn.action:
            item["key"] = btn.action
        result.append(item)
    return result


def _build_vote_options(selects: tuple[Any, ...]) -> list[dict[str, Any]]:
    """构建投票选择型 option。"""
    result: list[dict[str, Any]] = []
    for sel in selects:
        for opt in sel.options:
            result.append({"text": opt.label, "key": opt.value})
    return result


def _build_multiple_options(checkboxes: tuple[Any, ...]) -> list[dict[str, Any]]:
    """构建多项选择型 checkboxes。"""
    result: list[dict[str, Any]] = []
    for cb in checkboxes:
        for opt in cb.options:
            result.append({"text": opt.label, "key": opt.value})
    return result