"""Threads posting flow (2026-09 inline composer).

    1. navigate threads.com
    2. click the inline "What's new?" composer
    3. type text
    4. click Post button
    5. text clearing / post appearing = success
"""

import asyncio

from ..cdp import human_delay
from . import guard, require_text, validate_media
from ..selectors import THREADS as S

PLATFORM = "threads"


async def post(cdp_client, text, media_path=None, options=None):
    options = options or {}
    require_text(PLATFORM, text)
    validate_media(media_path)

    tab, reused = await cdp_client.get_or_open_tab(S["url"], "threads.com")
    if reused:
        await tab.eval("window.onbeforeunload = null")
        await tab.navigate(S["url"])
    return await guard(PLATFORM, tab, _flow(tab, text, media_path))


async def _flow(tab, text, media_path):
    # Wait for the inline composer to appear
    await _wait_for_composer(tab)
    await human_delay()

    # Click the composer input area
    await tab.click_js(S["composer_trigger_js"])
    await human_delay(0.5, 1.0)

    # Type into whichever input is now focused — could be a contenteditable
    # or a textbox that appeared after clicking
    textbox = await _find_active_input(tab)
    await tab.type_text(textbox, text)

    if media_path:
        if not await tab.exists(S["file_input"]):
            # Look for an attach media button near the composer
            await human_delay()
        if await tab.exists(S["file_input"]):
            await tab.set_file_input(S["file_input"], media_path)
            await human_delay(1.5, 3.0)

    await human_delay(0.5, 1.0)
    await tab.click_js(S["post_button_js"])

    # Success = the composer returns to its empty placeholder state
    await _wait_for_post_complete(tab)


async def _wait_for_composer(tab, timeout=20.0):
    deadline = asyncio.get_running_loop().time() + timeout
    while asyncio.get_running_loop().time() < deadline:
        has_input = await tab.eval(
            "!!(document.querySelector('[placeholder=\"What\\'s new?\"]')"
            " || [...document.querySelectorAll('span,div')]"
            ".find(e => e.innerText && e.innerText.trim() === 'What\\'s new?'))"
        )
        if has_input:
            return
        await asyncio.sleep(0.5)
    from ..cdp import CDPError
    raise CDPError("threads: composer ('What's new?') not found after 20s")


async def _find_active_input(tab):
    """After clicking the composer, find the actual text input element."""
    # Check for contenteditable first (Threads often uses these)
    for sel in ('[contenteditable="true"]', '[role="textbox"]', 'textarea',
                '[placeholder="What\'s new?"]'):
        if await tab.exists(sel):
            return sel
    from ..cdp import CDPError
    raise CDPError("threads: no text input found after clicking composer")


async def _wait_for_post_complete(tab, timeout=30.0):
    """Wait for the post to go through — composer empties or a toast appears."""
    deadline = asyncio.get_running_loop().time() + timeout
    while asyncio.get_running_loop().time() < deadline:
        # Check if the composer is back to empty placeholder state
        empty = await tab.eval(
            "(() => {"
            " const ce = document.querySelector('[contenteditable=\"true\"]');"
            " if (ce && ce.innerText.trim() === '') return true;"
            " const tb = document.querySelector('[role=\"textbox\"]');"
            " if (tb && tb.innerText.trim() === '') return true;"
            " return false;"
            "})()"
        )
        if empty:
            return
        await asyncio.sleep(0.5)
    from ..cdp import CDPError
    raise CDPError("threads: composer still has text 30s after clicking Post")


async def check_login(cdp_client):
    tab, reused = await cdp_client.get_or_open_tab(S["url"], "threads.com")
    if reused:
        await tab.eval("window.onbeforeunload = null")
        await tab.navigate(S["url"])
    await asyncio.sleep(4)
    if await tab.exists(S["login_marker"]):
        return False
    return await tab.eval(
        "!!(document.querySelector('[placeholder=\"What\\'s new?\"]')"
        " || [...document.querySelectorAll('span,div')]"
        ".find(e => e.innerText && e.innerText.trim() === 'What\\'s new?'))"
    )