"""
===============================================================================
FILE: services/tasks/exporter.py
PROJECT: SCUD Orion AI (Unified Architecture)
MODULE: services / tasks
ROLE: Экспорт задач в чистый Markdown и генерация прямой ссылки на скачивание.
===============================================================================
"""

import os
import uuid
from typing import Dict, Any, Optional
from config import BASE_DIR
from .repository import repo_get_tasks

WEB_OUTPUT_DIR = os.path.join(BASE_DIR, "output", "web", "db_export_tasks_markdown")


def export_tasks_to_markdown(
    user_id: int, 
    filename: Optional[str] = "ROADMAP.md", 
    status_filter: Optional[str] = None
) -> Dict[str, Any]:
    tasks = repo_get_tasks(user_id=user_id, status=status_filter)
    safe_filename = os.path.basename(filename or "ROADMAP.md")
    if not safe_filename.endswith(".md"):
        safe_filename += ".md"

    session_uuid = str(uuid.uuid4())[:8]
    target_dir = os.path.join(WEB_OUTPUT_DIR, session_uuid)
    os.makedirs(target_dir, exist_ok=True)
    target_filepath = os.path.join(target_dir, safe_filename)

    lines = [
        f"# 📋 Реестр задач проекта ({safe_filename})",
        f"**Всего задач:** {len(tasks)}  ",
        f"**Пользователь ID:** {user_id}  ",
        "",
        "| ID | Статус | Приоритет | Модуль | Срок | Задача |",
        "| :--- | :--- | :--- | :--- | :--- | :--- |"
    ]

    status_icons = {
        "IN_PROGRESS": "⚙️ В работе",
        "COMPLETED": "✓ Завершено",
        "BACKLOG": "📋 Бэклог"
    }

    for t in tasks:
        t_id = t.get("task_id") or f"#{t.get('id')}"
        t_status = status_icons.get(t.get("status"), t.get("status", "BACKLOG"))
        t_prio = t.get("priority", "MEDIUM")
        t_mod = t.get("module", "general")
        t_due = t.get("due_date") or "—"
        t_title = str(t.get("title", "")).replace("|", "\\|").strip()
        lines.append(f"| `{t_id}` | {t_status} | {t_prio} | `{t_mod}` | {t_due} | {t_title} |")

    lines.append("")
    content = "\n".join(lines)

    with open(target_filepath, "w", encoding="utf-8") as f:
        f.write(content)

    download_url = f"/api/v1/files/download/db_export_tasks_markdown/{session_uuid}/{safe_filename}"

    return {
        "status": "success",
        "message": f"Отчет успешно сформирован в файл `{safe_filename}` (всего задач: {len(tasks)}).",
        "filename": safe_filename,
        "download_url": download_url,
        "tasks_count": len(tasks)
    }