#!/usr/bin/env python3
"""Reels peeking: the next step plays as it slides in, and rewinds if it doesn't.

Run against a locally running backend:

    backend/main.py &
    .venv/bin/python tests/smoke_peek.py

A half-finished swipe is the thing under test, so the scroller's snapping is
switched off for the duration: a finger holds the list between two steps, and
`scrollTop` can only do the same with mandatory snapping out of the way.
"""
import sys
from playwright.sync_api import sync_playwright

BASE = "http://127.0.0.1:5000/"
SERVER = "https://hottubapp.io"
CHANNEL = "xvideos"

SEED = """([server, channel]) => {
    localStorage.setItem('config', JSON.stringify({ servers: [{ [server]: {} }] }));
    localStorage.setItem('preferences', JSON.stringify({ [server]: { channelId: channel } }));
    localStorage.removeItem('session');
}"""

# Every step in the window, by its index, with what its video is doing.
STEPS = """() => {
    const out = {};
    document.querySelectorAll('.feed-slide').forEach((slide) => {
        const video = slide.querySelector('.feed-video');
        out[slide.dataset.step] = {
            active: slide.classList.contains('is-active'),
            loaded: !!slide.querySelector('.feed-pane.is-loaded'),
            paused: video ? video.paused : null,
            muted: video ? video.muted : null,
            t: video ? Math.round(video.currentTime * 10) / 10 : null,
        };
    });
    return { steps: out, activeIndex: App.state.feedActiveIndex };
}"""

DRAG = """(fraction) => {
    const scroller = document.getElementById('feed-scroll');
    // A finger can hold the list between two steps; scrollTop can only do the
    // same with mandatory snapping out of the way.
    scroller.style.scrollSnapType = 'none';
    const height = scroller.clientHeight;
    scroller.scrollTop = Math.round(height * fraction);
    return scroller.scrollTop;
}"""


class Checks:
    def __init__(self):
        self.failed = 0

    def ok(self, label, condition, detail=""):
        mark = "PASS" if condition else "FAIL"
        if not condition:
            self.failed += 1
        print(f"  [{mark}] {label}" + (f" -- {detail}" if detail and not condition else ""))


def open_reels(page):
    page.goto(BASE, wait_until="domcontentloaded")
    page.evaluate(SEED, [SERVER, CHANNEL])
    page.goto(BASE, wait_until="load")
    page.wait_for_selector(".video-card", timeout=90000)
    page.wait_for_timeout(1500)
    page.evaluate("() => App.feed.open()")
    page.wait_for_selector(".feed-slide", timeout=20000)
    page.wait_for_timeout(4000)


def main():
    c = Checks()
    with sync_playwright() as p:
        browser = p.chromium.launch(args=[
            "--no-sandbox",
            "--disable-dev-shm-usage",
            "--disable-gpu",
            "--autoplay-policy=no-user-gesture-required",
            "--renderer-process-limit=1",
            "--js-flags=--max-old-space-size=512",
        ])
        page = browser.new_page(viewport={"width": 430, "height": 930})
        crashes = []
        page.on("pageerror", lambda e: crashes.append(str(e)))
        open_reels(page)

        start = page.evaluate(STEPS)
        c.ok("the first step is playing", start["steps"]["0"]["paused"] is False, str(start))

        print("\na swipe barely begun")
        page.evaluate(DRAG, 0.18)
        page.wait_for_timeout(1800)
        peek = page.evaluate(STEPS)
        nxt = peek["steps"].get("1")
        c.ok("the step sliding in is already playing", nxt and nxt["paused"] is False, str(peek))
        c.ok("silently, so it doesn't talk over the one being left",
             nxt and nxt["muted"] is True, str(nxt))
        c.ok("and the one being left plays on",
             peek["steps"]["0"]["paused"] is False, str(peek["steps"]["0"]))
        c.ok("without the swipe counting as done", peek["activeIndex"] == 0,
             str(peek["activeIndex"]))

        print("\nthinking better of it")
        page.evaluate(DRAG, 0)
        page.wait_for_timeout(1200)
        page.evaluate("() => App.feed._settlePeek()")
        page.wait_for_timeout(400)
        back = page.evaluate(STEPS)
        nxt = back["steps"].get("1")
        c.ok("the step that slid back in is stopped", nxt and nxt["paused"] is True, str(nxt))
        c.ok("and wound back to the start", nxt and nxt["t"] == 0, str(nxt))
        c.ok("the one being watched never stopped",
             back["steps"]["0"]["paused"] is False, str(back["steps"]["0"]))

        print("\nswiping again starts it from the top")
        page.evaluate(DRAG, 0.2)
        page.wait_for_timeout(1500)
        again = page.evaluate(STEPS)["steps"].get("1")
        c.ok("it plays again", again and again["paused"] is False, str(again))
        c.ok("from the beginning, not from where the first peek got to",
             again and again["t"] is not None and again["t"] < 2.5, str(again))

        print("\ncarrying the swipe through")
        page.evaluate(DRAG, 1)
        page.wait_for_timeout(2500)
        page.evaluate("() => App.feed._settlePeek()")
        page.wait_for_timeout(400)
        done = page.evaluate(STEPS)
        arrived = done["steps"].get("1")
        c.ok("the step arrived at is the active one", done["activeIndex"] == 1, str(done["activeIndex"]))
        c.ok("it is playing", arrived and arrived["paused"] is False, str(arrived))
        c.ok("it was never wound back", arrived and arrived["t"] > 0, str(arrived))
        c.ok("and it carries the feed's own sound setting",
             arrived and arrived["muted"] == page.evaluate("() => App.state.feedMuted !== false"),
             str(arrived))

        c.ok("nothing threw along the way", not crashes, str(crashes[:2]))
        browser.close()

    print(f"\n{'OK' if not c.failed else 'FAILED'}: {c.failed} check(s) failed")
    return 1 if c.failed else 0


sys.exit(main())