# retoor <retoor@molodetz.nl>

import logging
from datetime import datetime, timezone

from devplacepy.database import (
    db,
    get_follow_counts,
    get_table,
    get_user_post_count,
    get_user_rank,
)

logger = logging.getLogger(__name__)

MAX_BIO = 280
MAX_EXCERPT = 400
MAX_SOURCE = 1500
MAX_THREAD_MESSAGES = 6
MAX_MESSAGE = 240

TARGET_TABLES = {
    "post": "posts",
    "project": "projects",
    "gist": "gists",
    "news": "news",
}


def _truncate(text: str, limit: int) -> str:
    text = " ".join((text or "").split())
    if len(text) <= limit:
        return text
    return text[:limit].rstrip() + "..."


def _today() -> str:
    return datetime.now(timezone.utc).strftime("%d/%m/%Y")


def _author_block(user_uid: str) -> str:
    user = get_table("users").find_one(uid=user_uid)
    if not user:
        return ""
    stats = [
        f"role {user.get('role') or 'Member'}",
        f"level {user.get('level', 1)}",
        f"{user.get('stars', 0)} stars",
    ]
    try:
        stats.append(f"{get_user_post_count(user_uid)} posts")
    except Exception:
        pass
    try:
        rank = get_user_rank(user_uid)
        if rank:
            stats.append(f"rank #{rank}")
    except Exception:
        pass
    try:
        follows = get_follow_counts(user_uid)
        stats.append(f"{follows.get('followers', 0)} followers")
    except Exception:
        pass
    joined = (user.get("created_at") or "")[:10]
    if joined:
        stats.append(f"member since {joined}")
    line = f"Author: {user.get('username', '')} ({', '.join(stats)})."
    bio = _truncate(user.get("bio") or "", MAX_BIO)
    if bio:
        line += f' Bio: "{bio}".'
    return line


def _target_excerpt(target_type: str, target_uid: str) -> str:
    table = TARGET_TABLES.get(target_type)
    if not table or table not in db.tables or not target_uid:
        return ""
    row = get_table(table).find_one(uid=target_uid)
    if not row:
        return ""
    title = (row.get("title") or "").strip()
    body = _truncate(row.get("content") or row.get("description") or "", MAX_EXCERPT)
    label = f'the {target_type} "{title}"' if title else f"a {target_type}"
    text = f"This is a comment on {label}."
    if body:
        text += f' Excerpt: "{body}".'
    return text


def _comment_block(row: dict) -> str:
    target_type = row.get("target_type") or "post"
    target_uid = row.get("target_uid") or row.get("post_uid") or ""
    text = _target_excerpt(target_type, target_uid)
    parent_uid = row.get("parent_uid")
    if parent_uid and "comments" in db.tables:
        parent = get_table("comments").find_one(uid=parent_uid)
        if parent:
            text += f' In reply to: "{_truncate(parent.get("content") or "", MAX_EXCERPT)}".'
    return text


def _post_block(row: dict) -> str:
    topic = row.get("topic") or "general"
    text = f"This is a post (topic: {topic})."
    project_uid = row.get("project_uid")
    if project_uid and "projects" in db.tables:
        project = get_table("projects").find_one(uid=project_uid)
        if project and project.get("title"):
            text += f' Attached to the project "{project["title"]}".'
    return text


def _item_block(table: str, row: dict) -> str:
    kind = "project" if table == "projects" else "gist"
    title = (row.get("title") or "").strip()
    text = f'This is a {kind}' + (f' titled "{title}".' if title else ".")
    description = _truncate(row.get("description") or "", MAX_EXCERPT)
    if description:
        text += f' Description: "{description}".'
    if table == "gists":
        language = row.get("language") or "plaintext"
        source = _truncate(row.get("source_code") or "", MAX_SOURCE)
        text += f" Language: {language}."
        if source:
            text += f" Source code (reference only, do not include unless asked): {source}"
    return text


def _message_block(row: dict) -> str:
    sender_uid = row.get("sender_uid")
    receiver_uid = row.get("receiver_uid")
    receiver = get_table("users").find_one(uid=receiver_uid) if receiver_uid else None
    receiver_name = (receiver or {}).get("username") or "the recipient"
    text = f"This is a direct message to {receiver_name}."
    if "messages" not in db.tables or not sender_uid or not receiver_uid:
        return text
    rows = list(
        db.query(
            "SELECT sender_uid, content FROM messages "
            "WHERE ((sender_uid = :a AND receiver_uid = :b) "
            "OR (sender_uid = :b AND receiver_uid = :a)) "
            "AND uid != :current AND deleted_at IS NULL "
            "ORDER BY id DESC LIMIT :lim",
            a=sender_uid,
            b=receiver_uid,
            current=row.get("uid") or "",
            lim=MAX_THREAD_MESSAGES,
        )
    )
    if not rows:
        return text
    lines = []
    for entry in reversed(rows):
        who = "you" if entry["sender_uid"] == sender_uid else receiver_name
        lines.append(f"{who}: {_truncate(entry['content'] or '', MAX_MESSAGE)}")
    return text + " Recent conversation:\n" + "\n".join(lines)


def _location_block(table: str, row: dict) -> str:
    if table == "comments":
        return _comment_block(row)
    if table == "posts":
        return _post_block(row)
    if table in ("projects", "gists"):
        return _item_block(table, row)
    if table == "messages":
        return _message_block(row)
    return ""


def build_context(table: str, uid: str, row: dict, user_uid: str) -> str:
    parts = [f"Today is {_today()} on the DevPlace developer network."]
    try:
        author = _author_block(user_uid)
        if author:
            parts.append(author)
    except Exception as exc:
        logger.warning("ai context author block failed: %s", exc)
    try:
        location = _location_block(table, row)
        if location:
            parts.append(location)
    except Exception as exc:
        logger.warning("ai context location block failed: %s", exc)
    return "\n".join(parts)