"""Pure parsers for inbound DingTalk ``ChatbotMessage`` payloads (no I/O, no adapter state)."""

import json
from typing import Any, List, Optional, Tuple

from gateway.platforms.base import MessageType

# DingTalk rich-text item type → runtime content type
DINGTALK_TYPE_MAPPING = {"picture": "image", "voice": "audio"}

# File extension → MIME type for DingTalk file/image messages. image/* MIMEs
# make ``extract_media`` classify msgtype='image'/'file' payloads as PHOTO.
EXT_MAP = {
    "pdf": "application/pdf", "doc": "application/msword", "xls": "application/vnd.ms-excel",
    "docx": "application/vnd.openxmlformats-officedocument.wordprocessingml.document",
    "xlsx": "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
    "png": "image/png", "jpg": "image/jpeg", "jpeg": "image/jpeg", "gif": "image/gif", "webp": "image/webp",
    "md": "text/markdown", "txt": "text/plain", "csv": "text/csv", "zip": "application/zip", "mp4": "video/mp4",
}

# rich-text runtime type → (media_types entry, MessageType promotion when still TEXT)
_RICH_MEDIA = {
    "image": ("image", MessageType.PHOTO),
    "video": ("video", MessageType.VIDEO),
    "file": ("application/octet-stream", MessageType.DOCUMENT),
}


def _extensions(message: Any) -> Any:
    return getattr(message, "extensions", {}) or {}


def _ext_content(message: Any) -> Optional[dict]:
    """``extensions['content']`` when it is a dict, else None."""
    content = _extensions(message).get("content", {})
    return content if isinstance(content, dict) else None


def _rich_list(message: Any) -> Optional[list]:
    """Rich-text item list from either SDK shape (``rich_text_content.rich_text_list`` or legacy ``rich_text``)."""
    rich_text = getattr(message, "rich_text_content", None) or getattr(message, "rich_text", None)
    if not rich_text:
        return None
    rich_list = getattr(rich_text, "rich_text_list", None) or rich_text
    return rich_list if isinstance(rich_list, list) else None


def _card_text(message: Any) -> str:
    """msgtype='card' (钉钉文档分享卡片 / link card): title + doc URL from ``extensions['card']``."""
    extensions = _extensions(message)
    content = ""
    card = extensions.get("card", {})
    if isinstance(card, dict):
        title = card.get("title", "")
        raw_content = card.get("content", "")
        doc_url = ""
        if isinstance(raw_content, dict):
            doc_url = raw_content.get("url", "") or raw_content.get("docUrl", "")
        elif isinstance(raw_content, str) and raw_content.strip():
            try:
                parsed = json.loads(raw_content.strip())
                if isinstance(parsed, dict):
                    doc_url = parsed.get("url", "") or parsed.get("docUrl", "")
            except (ValueError, TypeError):
                doc_url = raw_content
        parts = ([f"[文档] {title}"] if title else []) + ([doc_url] if doc_url else [])
        if parts:
            content = " ".join(parts)
    if not content:
        # Last-resort: raw text field from extensions (if present)
        ext_text = extensions.get("text", {})
        if isinstance(ext_text, dict):
            content = (ext_text.get("content", "") or "").strip()
    return content


def _interactive_card_text(message: Any) -> str:
    """msgtype='interactiveCard': ``extensions['content']`` carries title + biz_custom_action_url."""
    ext_content = _ext_content(message)
    if not ext_content:
        return ""
    doc_url = ext_content.get("biz_custom_action_url", "")
    title = ext_content.get("title", "")
    if not (doc_url or title):
        return ""
    parts = [f"[文档卡片] {title}" if title else "[文档卡片]"] + ([doc_url] if doc_url else [])
    return " ".join(parts)


def _ext_field(message: Any, field: str) -> Any:
    ext_content = _ext_content(message)
    return ext_content.get(field, "") if ext_content else ""


def _audio_text(message: Any) -> str:
    """msgtype='audio': DingTalk-provided speech recognition text."""
    recognition = _ext_field(message, "recognition")
    return recognition.strip() if recognition else ""


def _file_text(message: Any) -> str:
    """msgtype='file': use fileName as text."""
    fname = _ext_field(message, "fileName")
    return f"[文件] {fname}" if fname else ""


# Fallbacks by msgtype when no plain/rich text was found (types are exclusive).
_EMPTY_TEXT_FALLBACKS = (
    ("audio", _audio_text),
    ("file", _file_text),
    ("card", _card_text),
    ("interactiveCard", _interactive_card_text),
)


def extract_text(message: Any) -> str:
    """Extract plain text from a DingTalk chatbot message.

    Handles both SDK payload shapes: legacy ``message.text`` dict ``{"content": ...}`` and
    >= 0.20 ``TextContent`` (whose ``__str__`` is ``"TextContent(content=...)"`` — always read
    ``.content`` first); rich text via ``rich_text_content.rich_text_list`` or legacy ``rich_text``.
    """
    text = getattr(message, "text", None) or ""
    if hasattr(text, "content"):
        content = (text.content or "").strip()
    elif isinstance(text, dict):
        content = text.get("content", "").strip()
    else:
        content = str(text).strip()

    if not content:
        rich_list = _rich_list(message)
        if rich_list is not None:
            parts = []
            for item in rich_list:
                if isinstance(item, dict):
                    t = item.get("text") or item.get("content") or ""
                    if t:
                        parts.append(t)
                elif hasattr(item, "text") and item.text:
                    parts.append(item.text)
            content = " ".join(parts).strip()

    if not content:
        msg_type = getattr(message, "message_type", "")
        for kind, fallback in _EMPTY_TEXT_FALLBACKS:
            if msg_type == kind:
                content = fallback(message)
                break

    # Do NOT strip "@bot": the mention is routed structurally (callback ``isInAtList``), and
    # regex-stripping @handles would damage e-mails, SSH URLs and literal "@openai" references.
    return content


def extract_media(message: Any) -> Tuple[MessageType, List[str], List[str]]:
    """Return ``(MessageType, [download codes/urls], [mime types])`` for a message."""
    msg_type = MessageType.TEXT
    media_urls: List[str] = []
    media_types: List[str] = []

    image_content = getattr(message, "image_content", None)
    if image_content:
        download_code = getattr(image_content, "download_code", None)
        if download_code:
            media_urls.append(download_code)
            media_types.append("image")
            msg_type = MessageType.PHOTO

    for item in _rich_list(message) or ():
        if not isinstance(item, dict):
            continue
        dl_code = item.get("downloadCode") or item.get("download_code") or ""
        item_type = item.get("type", "")
        if not dl_code:
            continue
        mapped = DINGTALK_TYPE_MAPPING.get(item_type, "file")
        media_urls.append(dl_code)
        if mapped == "audio":
            media_types.append("audio")
            if msg_type == MessageType.TEXT:
                # "voice" items are native voice notes → STT (VOICE); "audio" file uploads stay AUDIO.
                msg_type = MessageType.VOICE if item_type == "voice" else MessageType.AUDIO
        else:
            mime, promoted = _RICH_MEDIA[mapped]
            media_types.append(mime)
            if msg_type == MessageType.TEXT:
                msg_type = promoted

    msg_type_str = getattr(message, "message_type", "") or ""
    if msg_type_str == "picture" and not media_urls:
        msg_type = MessageType.PHOTO
    elif msg_type_str == "richText":
        # Only re-derive when the scan above left TEXT — resetting a VOICE/AUDIO/VIDEO/DOCUMENT
        # promotion here dropped native voice notes back to TEXT and skipped STT.
        if msg_type == MessageType.TEXT and any("image" in t for t in media_types):
            msg_type = MessageType.PHOTO
    elif msg_type_str == "audio":
        # Voice message: recognition text is already in the text. Do NOT add media_urls, or
        # run.py's transcription enrichment overwrites it with a failed STT attempt.
        if msg_type == MessageType.TEXT:
            msg_type = MessageType.VOICE
    elif msg_type_str in ("file", "image"):
        ext_content = _ext_content(message)
        if ext_content:
            dl_code = ext_content.get("downloadCode") or ""
            fname = ext_content.get("fileName", "")
            if dl_code:
                media_urls.append(dl_code)
                mime = "application/octet-stream"
                if fname:
                    ext = fname.rsplit(".", 1)[-1].lower() if "." in fname else ""
                    mime = EXT_MAP.get(ext, mime)
                media_types.append(mime)
                if msg_type == MessageType.TEXT:
                    # Image messages, and files with image MIME (a .png sent as attachment), → PHOTO.
                    if msg_type_str == "image" or mime.startswith("image/"):
                        msg_type = MessageType.PHOTO
                    else:
                        msg_type = MessageType.DOCUMENT

    return msg_type, media_urls, media_types


def collect_download_codes(message: Any) -> List[Tuple[Any, str]]:
    """Return ``(container, key)`` pairs whose download code should be resolved to a URL."""
    codes: List[Tuple[Any, str]] = []
    img_content = getattr(message, "image_content", None)
    if img_content and getattr(img_content, "download_code", None):
        codes.append((img_content, "download_code"))
    rich_text = getattr(message, "rich_text_content", None)
    if rich_text:
        for item in getattr(rich_text, "rich_text_list", []) or []:
            if isinstance(item, dict):
                for key in ("downloadCode", "pictureDownloadCode", "download_code"):
                    if item.get(key):
                        codes.append((item, key))
    if (getattr(message, "message_type", "") or "") in ("file", "image"):
        ext_content = _ext_content(message)
        if ext_content and ext_content.get("downloadCode"):
            codes.append((ext_content, "downloadCode"))
    return codes