# utils/boxapi_parser.py
from typing import Any, Dict, List, Optional
from datetime import datetime

def _ts_to_dt(ts: Optional[int]) -> datetime:
    # BoxAPI/IG timestamps appear to be epoch seconds
    if ts is None:
        return datetime.utcnow()
    return datetime.utcfromtimestamp(int(ts))

def pick_image_urls(item: Dict[str, Any]) -> List[str]:
    urls: List[str] = []
    image_versions2 = item.get("image_versions2") or {}
    for c in image_versions2.get("candidates", []):
        u = c.get("url")
        if u:
            urls.append(u)
    # Fallback to additional_candidates.first_frame if exists
    add = image_versions2.get("additional_candidates") or {}
    first_frame = add.get("first_frame") or {}
    if first_frame.get("url"):
        urls.append(first_frame["url"])
    return list(dict.fromkeys(urls))  # dedupe

def pick_video_urls(item: Dict[str, Any]) -> List[str]:
    urls: List[str] = []
    for v in item.get("video_versions", []) or []:
        u = v.get("url")
        if u:
            urls.append(u)
    # Fallback: progressive_download_url if present
    prog = (item.get("clips_metadata") or {}).get("original_sound_info") or {}
    prog_url = prog.get("progressive_download_url")
    if prog_url:
        urls.append(prog_url)
    return list(dict.fromkeys(urls))

def parse_boxapi_items(items: List[Dict[str, Any]]) -> List[Dict[str, Any]]:
    """
    Normalized items for storage:
    {
      "ig_post_id": str,
      "media_type": "image"|"video"|"carousel",
      "caption": str,
      "taken_at": datetime,
      "thumbnail_url": Optional[str],
      "remote_urls": List[str],  # to be uploaded to S3
      "code": Optional[str]
    }
    """
    out: List[Dict[str, Any]] = []
    for it in items:
        mt_raw = it.get("media_type")
        if mt_raw == 1:
            mtype = "image"
            remote_urls = pick_image_urls(it)
        elif mt_raw == 2:
            mtype = "video"
            remote_urls = pick_video_urls(it)
            # Add a cover frame if available (first image candidate)
            cover = pick_image_urls(it)[:1]
            remote_urls = cover + remote_urls
        elif mt_raw == 8:  # carousel, if BoxAPI returns it
            mtype = "carousel"
            remote_urls = []
            for child in it.get("carousel_media", []) or []:
                if child.get("media_type") == 1:
                    remote_urls += pick_image_urls(child)
                elif child.get("media_type") == 2:
                    # put a cover first if exists
                    cover = pick_image_urls(child)[:1]
                    remote_urls += cover + pick_video_urls(child)
        else:
            # Unknown, skip
            continue

        cap = (it.get("caption") or {}).get("text") or ""
        thumb = (it.get("image_versions2") or {}).get("candidates", [{}])[0].get("url")
        out.append({
            "ig_post_id": str(it.get("pk") or it.get("id") or ""),
            "media_type": mtype,
            "caption": cap,
            "taken_at": _ts_to_dt(it.get("taken_at")),
            "thumbnail_url": thumb,
            "remote_urls": remote_urls,
            "code": it.get("code"),
        })
    return out