"""Links: URL references attached to domains/projects/tasks/meetings."""

from fastapi import APIRouter, Request, Form, Depends
from fastapi.templating import Jinja2Templates
from fastapi.responses import RedirectResponse
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy import text
from typing import Optional

from core.database import get_db
from core.base_repository import BaseRepository
from core.sidebar import get_sidebar_data
from routers.weblinks import get_default_folder_id

router = APIRouter(prefix="/links", tags=["links"])
templates = Jinja2Templates(directory="templates")


@router.get("/")
async def list_links(request: Request, domain_id: Optional[str] = None, db: AsyncSession = Depends(get_db)):
    sidebar = await get_sidebar_data(db)
    where_clauses = ["l.is_deleted = false"]
    params = {}
    if domain_id:
        where_clauses.append("l.domain_id = :domain_id")
        params["domain_id"] = domain_id
    where_sql = " AND ".join(where_clauses)

    result = await db.execute(text(f"""
        SELECT l.*, d.name as domain_name, d.color as domain_color, p.name as project_name
        FROM links l
        LEFT JOIN domains d ON l.domain_id = d.id
        LEFT JOIN projects p ON l.project_id = p.id
        WHERE {where_sql} ORDER BY l.sort_order, l.created_at
    """), params)
    items = [dict(r._mapping) for r in result]

    domains_repo = BaseRepository("domains", db)
    domains = await domains_repo.list()

    return templates.TemplateResponse("links.html", {
        "request": request, "sidebar": sidebar, "items": items, "domains": domains,
        "current_domain_id": domain_id or "",
        "page_title": "Links", "active_nav": "links",
    })


@router.get("/create")
async def create_form(
    request: Request,
    domain_id: Optional[str] = None,
    project_id: Optional[str] = None,
    task_id: Optional[str] = None,
    meeting_id: Optional[str] = None,
    db: AsyncSession = Depends(get_db),
):
    sidebar = await get_sidebar_data(db)
    domains_repo = BaseRepository("domains", db)
    domains = await domains_repo.list()
    projects_repo = BaseRepository("projects", db)
    projects = await projects_repo.list()
    return templates.TemplateResponse("link_form.html", {
        "request": request, "sidebar": sidebar, "domains": domains, "projects": projects,
        "page_title": "New Link", "active_nav": "links",
        "item": None,
        "prefill_domain_id": domain_id or "",
        "prefill_project_id": project_id or "",
        "prefill_task_id": task_id or "",
        "prefill_meeting_id": meeting_id or "",
    })


@router.post("/create")
async def create_link(
    request: Request, label: str = Form(...), url: str = Form(...),
    domain_id: Optional[str] = Form(None), project_id: Optional[str] = Form(None),
    task_id: Optional[str] = Form(None), meeting_id: Optional[str] = Form(None),
    description: Optional[str] = Form(None), tags: Optional[str] = Form(None),
    db: AsyncSession = Depends(get_db),
):
    repo = BaseRepository("links", db)
    data = {"label": label, "url": url, "description": description}
    if domain_id and domain_id.strip():
        data["domain_id"] = domain_id
    if project_id and project_id.strip():
        data["project_id"] = project_id
    if task_id and task_id.strip():
        data["task_id"] = task_id
    if meeting_id and meeting_id.strip():
        data["meeting_id"] = meeting_id
    if tags and tags.strip():
        data["tags"] = [t.strip() for t in tags.split(",") if t.strip()]
    link = await repo.create(data)

    # Assign to Default folder
    default_fid = await get_default_folder_id(db)
    await db.execute(text("""
        INSERT INTO folder_links (folder_id, link_id)
        VALUES (:fid, :lid) ON CONFLICT DO NOTHING
    """), {"fid": default_fid, "lid": link["id"]})

    # Redirect back to context if created from task/meeting
    if task_id and task_id.strip():
        return RedirectResponse(url=f"/tasks/{task_id}?tab=links", status_code=303)
    if meeting_id and meeting_id.strip():
        return RedirectResponse(url=f"/meetings/{meeting_id}?tab=links", status_code=303)
    return RedirectResponse(url="/links", status_code=303)


@router.get("/{link_id}/edit")
async def edit_form(link_id: str, request: Request, db: AsyncSession = Depends(get_db)):
    repo = BaseRepository("links", db)
    sidebar = await get_sidebar_data(db)
    item = await repo.get(link_id)
    if not item:
        return RedirectResponse(url="/links", status_code=303)
    domains_repo = BaseRepository("domains", db)
    domains = await domains_repo.list()
    projects_repo = BaseRepository("projects", db)
    projects = await projects_repo.list()
    return templates.TemplateResponse("link_form.html", {
        "request": request, "sidebar": sidebar, "domains": domains, "projects": projects,
        "page_title": "Edit Link", "active_nav": "links",
        "item": item,
        "prefill_domain_id": "", "prefill_project_id": "",
        "prefill_task_id": "", "prefill_meeting_id": "",
    })


@router.post("/{link_id}/edit")
async def update_link(
    link_id: str, label: str = Form(...), url: str = Form(...),
    domain_id: Optional[str] = Form(None), project_id: Optional[str] = Form(None),
    description: Optional[str] = Form(None), tags: Optional[str] = Form(None),
    db: AsyncSession = Depends(get_db),
):
    repo = BaseRepository("links", db)
    data = {
        "label": label, "url": url,
        "domain_id": domain_id if domain_id and domain_id.strip() else None,
        "project_id": project_id if project_id and project_id.strip() else None,
        "description": description,
    }
    if tags and tags.strip():
        data["tags"] = [t.strip() for t in tags.split(",") if t.strip()]
    else:
        data["tags"] = None
    await repo.update(link_id, data)
    return RedirectResponse(url="/links", status_code=303)


@router.post("/{link_id}/delete")
async def delete_link(link_id: str, request: Request, db: AsyncSession = Depends(get_db)):
    repo = BaseRepository("links", db)
    await repo.soft_delete(link_id)
    return RedirectResponse(url=request.headers.get("referer", "/links"), status_code=303)