from flask import Blueprint, abort, flash, redirect, render_template
from sqlalchemy import select, func

from ..models import Page, PageTag, db
from .. import app_config

bp = Blueprint('home', __name__)

@bp.route('/')
def homepage():
    page_limit = app_config.default_items_per_page
    new_notes = db.paginate(select(Page).order_by(Page.touched.desc()).limit(page_limit))
    return render_template('home.html',
        new_notes = new_notes)

@bp.route('/p/most_recent/')
def view_most_recent():
    general_query = db.paginate(select(Page).order_by(Page.touched.desc()))
    return render_template('listrecent.html', notes=general_query)

@bp.route('/p/random/')
def view_random():
    page = None
    page_count = db.session.execute(select(func.count()).select_from(Page)).scalar()
    if page_count < 4:
        flash('Too few pages in this site.')
        abort(404)
    while not page:
        page = db.session.execute(select(Page).order_by(func.random())).scalar()
    return redirect(page.get_url())

@bp.route('/p/leaderboard/')
def page_leaderboard():
    headers = {
        'Cache-Control': 'max-age=180, stale-while-revalidate=1800'
    }

    pages = []
    ## TODO make it a query
    pages_q = db.session.execute(select(Page)).scalars()
    for p in pages_q:
        p_latest = p.latest()
        score = (p_latest.length >> 10) + len(p.forward_links) + len(p.back_links)
        ## TODO make it a namedtuple
        pages.append((p, score, len(p.back_links.count), len(p.forward_links), p_latest.length))
    pages.sort(key = lambda x: (x[1], x[2], x[4], x[3]), reverse = True)
        
    return render_template('leaderboard.html', pages=pages), headers

@bp.route('/tags/<slug:tag>/')
def listtag(tag):
    general_query = select(Page).join(PageTag, PageTag.page_id == Page.id).where(PageTag.name == tag).order_by(Page.touched.desc())
    return render_template('listtag.html', tagname=tag, tagged_notes=db.paginate(general_query))