app.py

import logging
import os
import random
import time
import traceback
from io import BytesIO

import gradio as gr
import requests
from PIL import Image
from dotenv import load_dotenv

logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s'
)
logger = logging.getLogger(__name__)

load_dotenv()

# API Configuration (new style: host + gen_image_path)
API_TOKEN = os.environ.get("token")
API_HOST = os.environ.get("host")
GEN_IMAGE_PATH = os.environ.get("gen_image_path")
MODEL_ID = os.environ.get("model_id")

# Polling / retry configuration (with sensible defaults)
MAX_RETRY_COUNT = int(os.environ.get("MAX_RETRY_COUNT", 3))
POLL_INTERVAL = float(os.environ.get("POLL_INTERVAL", 2.0))
MAX_POLL_TIME = int(os.environ.get("MAX_POLL_TIME", 300))

# Local-only test mode: skip the real API and return a random-colored image after
# a randomised delay. Useful for testing the UI / queueing flow without burning
# real model credits. Enable with FAKE_TEST=1 (also accepts "true"/"yes").
FAKE_TEST = os.environ.get("FAKE_TEST", "").strip().lower() in ("1", "true", "yes", "on")

# Predefined aspect ratios (wh_ratio) — kept in the same order as the original
# (width, height) list so each entry mirrors the previous resolution choice:
#   1:1  ←→ 2048×2048   4:3  ←→ 2304×1728   3:4  ←→ 1728×2304
#  16:9  ←→ 2560×1440   9:16 ←→ 1440×2560   3:2  ←→ 2496×1664
#   2:3  ←→ 1664×2496  21:9  ←→ 3104×1312   9:21 ←→ 1312×3104
#   9:7  ←→ 2304×1792   7:9  ←→ 1792×2304
WH_RATIO_OPTIONS = [
    "1:1",
    "4:3",
    "3:4",
    "16:9",
    "9:16",
    "3:2",
    "2:3",
    "21:9",
    "9:21",
    "9:7",
    "7:9",
]

logger.info(
    f"API configuration loaded: HOST={API_HOST}, GEN_IMAGE_PATH={GEN_IMAGE_PATH}, MODEL_ID={MODEL_ID}"
)
logger.info(
    f"Retry configuration: MAX_RETRY_COUNT={MAX_RETRY_COUNT}, POLL_INTERVAL={POLL_INTERVAL}s, MAX_POLL_TIME={MAX_POLL_TIME}s"
)
if FAKE_TEST:
    logger.warning("FAKE_TEST mode is ENABLED — no real API calls will be made.")


class APIError(Exception):
    """Custom exception for API-related errors"""
    pass


# Status codes returned by the API
SUCCESS_CODE = 0


def _build_request_url() -> str:
    if not API_HOST or not GEN_IMAGE_PATH:
        raise APIError("API host or gen_image_path is not configured. Please set the 'host' and 'gen_image_path' environment variables.")
    return f"{API_HOST.rstrip('/')}{GEN_IMAGE_PATH}"


def _build_result_url(task_id: str) -> str:
    return f"{_build_request_url()}/results?task_id={task_id}"


def _headers() -> dict:
    if not API_TOKEN:
        raise APIError("API token is not configured. Please set the 'token' environment variable.")
    return {"Authorization": f"Bearer {API_TOKEN}"}


def create_request(
    prompt,
    wh_ratio,
    negative_prompt="",
    enable_prompt_refine=True,
    seed=-1,
    guidance_scale=5.0,
):
    """
    Submit an image generation request to the API.

    Args:
        prompt (str): Text prompt describing the image to generate
        wh_ratio (str): Aspect ratio for the output image (e.g. "16:9")
        negative_prompt (str): Optional text describing what to avoid.
        enable_prompt_refine (bool): Whether to let the backend rewrite/expand
            the prompt before generation. Sent to the API as 0 / 1.
        seed (int): Generation seed. -1 means the backend will pick one
            randomly; any other integer fixes the seed for reproducible runs.
        guidance_scale (float): Classifier-free guidance strength. Higher
            values follow the prompt more strictly.

    Returns:
        str: Task ID

    Raises:
        APIError: If the API request fails
    """
    logger.info(
        f"Starting create_request with prompt='{prompt[:50]}...', "
        f"wh_ratio={wh_ratio}, enable_prompt_refine={enable_prompt_refine}, "
        f"seed={seed}, guidance_scale={guidance_scale}, "
        f"negative_prompt='{(negative_prompt or '')[:30]}...'"
    )

    if not prompt or not prompt.strip():
        logger.error("Empty prompt provided to create_request")
        raise ValueError("Prompt cannot be empty")

    if not wh_ratio or not isinstance(wh_ratio, str) or wh_ratio not in WH_RATIO_OPTIONS:
        logger.error(f"Invalid wh_ratio: {wh_ratio}. Valid options: {WH_RATIO_OPTIONS}")
        raise ValueError(f"Invalid aspect ratio. Must be one of: {', '.join(WH_RATIO_OPTIONS)}")

    try:
        seed_int = int(seed)
    except (TypeError, ValueError):
        logger.warning(f"Invalid seed value '{seed}', falling back to -1 (random)")
        seed_int = -1

    try:
        guidance_scale_f = float(guidance_scale)
    except (TypeError, ValueError):
        logger.warning(f"Invalid guidance_scale '{guidance_scale}', falling back to 5.0")
        guidance_scale_f = 5.0

    model_params = {
        "prompt": prompt,
        "wh_ratio": wh_ratio,
        "model_id": MODEL_ID,
        "n": 1,
        "negative_prompt": negative_prompt or "",
        "enable_prompt_refine": 1 if enable_prompt_refine else 0,
        "seed": seed_int,
        "guidance_scale": guidance_scale_f,
    }

    url = _build_request_url()

    retry_count = 0
    while retry_count < MAX_RETRY_COUNT:
        try:
            logger.info(
                f"Sending API request [attempt {retry_count + 1}/{MAX_RETRY_COUNT}] for prompt: '{prompt[:50]}...'"
            )
            response = requests.post(url, json=model_params, headers=_headers(), timeout=15)
            logger.info(f"API request response status: {response.status_code}")
            response.raise_for_status()

            response_json = response.json()
            code = response_json.get("code")
            message = response_json.get("message", "")
            if code != SUCCESS_CODE:
                logger.error(f"API returned error code {code}: {message}")
                raise APIError(f"Failed to submit task (code={code}): {message}")

            task_id = response_json.get("result", {}).get("task_id")
            if not task_id:
                logger.error(f"No task ID in API response: {response_json}")
                raise APIError(f"No task ID returned from API: {response_json}")

            logger.info(f"Successfully created task with ID: {task_id}")
            return task_id

        except requests.exceptions.Timeout:
            retry_count += 1
            logger.warning(f"Request timed out. Retrying ({retry_count}/{MAX_RETRY_COUNT})...")
            time.sleep(1)

        except requests.exceptions.HTTPError as e:
            status_code = e.response.status_code
            error_message = f"HTTP error {status_code}"
            try:
                error_detail = e.response.json()
                error_message += f": {error_detail}"
                logger.error(f"API response error content: {error_detail}")
            except Exception:
                logger.error(f"Could not parse API error response as JSON. Raw content: {e.response.content[:500]}")

            if status_code == 401:
                logger.error(f"Authentication failed with API token. Status code: {status_code}")
                raise APIError("Authentication failed. Please check your API token.")
            elif status_code == 429:
                retry_count += 1
                wait_time = min(2 ** retry_count, 10)
                logger.warning(f"Rate limit exceeded. Waiting {wait_time}s before retry ({retry_count}/{MAX_RETRY_COUNT})...")
                time.sleep(wait_time)
            elif 400 <= status_code < 500:
                logger.error(f"Client error: {error_message}, Prompt: '{prompt[:50]}...', Status: {status_code}")
                raise APIError(error_message)
            else:
                retry_count += 1
                logger.warning(f"Server error: {error_message}. Retrying ({retry_count}/{MAX_RETRY_COUNT})...")
                time.sleep(1)

        except requests.exceptions.RequestException as e:
            logger.error(f"Request error: {str(e)}")
            logger.debug(f"Request error details: {traceback.format_exc()}")
            raise APIError(f"Failed to connect to API: {str(e)}")

        except APIError:
            raise

        except Exception as e:
            logger.error(f"Unexpected error in create_request: {str(e)}")
            logger.error(f"Full traceback: {traceback.format_exc()}")
            raise APIError(f"Unexpected error: {str(e)}")

    logger.error(f"Failed to create request after {MAX_RETRY_COUNT} retries for prompt: '{prompt[:50]}...'")
    raise APIError(f"Failed after {MAX_RETRY_COUNT} retries")


def get_results(task_id):
    """
    Check the status of an image generation task.

    Args:
        task_id (str): The task ID to check

    Returns:
        dict: Task result information (the "result" object from the response), or None on transient failure.

    Raises:
        APIError: For unrecoverable errors (e.g. authentication failure).
    """
    logger.debug(f"Checking status for task ID: {task_id}")

    if not task_id:
        logger.error("Empty task ID provided to get_results")
        raise ValueError("Task ID cannot be empty")

    url = _build_result_url(task_id)

    try:
        response = requests.get(url, headers=_headers(), timeout=10)
        logger.debug(f"Status check response code: {response.status_code}")
        response.raise_for_status()
        response_json = response.json()

        code = response_json.get("code")
        message = response_json.get("message", "")
        if code != SUCCESS_CODE:
            logger.warning(f"API returned non-success code {code} for task {task_id}: {message}")
            return None

        return response_json.get("result")

    except requests.exceptions.Timeout:
        logger.warning(f"Request timed out when checking task {task_id}")
        return None

    except requests.exceptions.HTTPError as e:
        status_code = e.response.status_code
        logger.warning(f"HTTP error {status_code} when checking task {task_id}")
        try:
            error_content = e.response.json()
            logger.error(f"Error response content: {error_content}")
        except Exception:
            logger.error(f"Could not parse error response as JSON. Raw content: {e.response.content[:500]}")

        if status_code == 401:
            logger.error(f"Authentication failed when checking task {task_id}")
            raise APIError(f"Authentication failed. Please check your API token when checking task {task_id}")
        elif 400 <= status_code < 500:
            logger.error(f"Client error {status_code} when checking task {task_id}")
            return None
        else:
            logger.warning(f"Server error {status_code} when checking task {task_id}")
            return None

    except requests.exceptions.RequestException as e:
        logger.warning(f"Network error when checking task {task_id}: {str(e)}")
        logger.debug(f"Network error details: {traceback.format_exc()}")
        return None

    except Exception as e:
        logger.error(f"Unexpected error when checking task {task_id}: {str(e)}")
        logger.error(f"Full traceback: {traceback.format_exc()}")
        return None


def download_image(image_url):
    """
    Download an image from a URL and return it as a PIL Image.
    Converts non-PNG formats (e.g. WebP) to PNG while preserving original metadata.
    """
    logger.info(f"Starting download_image from URL: {image_url}")

    if not image_url:
        logger.error("Empty image URL provided to download_image")
        raise ValueError("Image URL cannot be empty when downloading image")

    retry_count = 0
    while retry_count < MAX_RETRY_COUNT:
        try:
            logger.info(f"Downloading image [attempt {retry_count + 1}/{MAX_RETRY_COUNT}] from {image_url}")
            response = requests.get(image_url, timeout=30)
            logger.debug(
                f"Image download response status: {response.status_code}, "
                f"Content-Type: {response.headers.get('Content-Type')}, "
                f"Content-Length: {response.headers.get('Content-Length')}"
            )
            response.raise_for_status()

            image = Image.open(BytesIO(response.content))
            logger.info(
                f"Image opened successfully. Format: {image.format}, "
                f"Size: {image.size[0]}x{image.size[1]}, Mode: {image.mode}"
            )

            original_metadata = {}
            for key, value in image.info.items():
                if isinstance(key, str) and isinstance(value, str):
                    original_metadata[key] = value
            logger.debug(f"Original image metadata: {original_metadata}")

            if image.format != 'PNG':
                logger.info(f"Converting image from {image.format} to PNG format")
                png_buffer = BytesIO()
                if 'A' in image.getbands():
                    image_to_save = image
                else:
                    image_to_save = image.convert('RGB')
                image_to_save.save(png_buffer, format='PNG')
                png_buffer.seek(0)
                image = Image.open(png_buffer)
                for key, value in original_metadata.items():
                    image.info[key] = value

            logger.info(f"Successfully downloaded and processed image: {image.size[0]}x{image.size[1]}")
            return image

        except requests.exceptions.Timeout:
            retry_count += 1
            logger.warning(f"Download timed out. Retrying ({retry_count}/{MAX_RETRY_COUNT})...")
            time.sleep(1)

        except requests.exceptions.HTTPError as e:
            status_code = e.response.status_code
            logger.error(f"HTTP error {status_code} when downloading image from {image_url}")
            if 400 <= status_code < 500:
                raise APIError(f"HTTP error {status_code} when downloading image")
            else:
                retry_count += 1
                time.sleep(1)

        except requests.exceptions.RequestException as e:
            retry_count += 1
            logger.warning(f"Network error during image download: {str(e)}. Retrying ({retry_count}/{MAX_RETRY_COUNT})...")
            time.sleep(1)

        except Exception as e:
            logger.error(f"Error processing image from {image_url}: {str(e)}")
            logger.error(f"Full traceback: {traceback.format_exc()}")
            raise APIError(f"Failed to process image: {str(e)}")

    logger.error(f"Failed to download image from {image_url} after {MAX_RETRY_COUNT} retries")
    raise APIError(f"Failed to download image after {MAX_RETRY_COUNT} retries")


APPLE_CSS = """
/* ---- Apple-inspired minimalist UI ---- */
.gradio-container {
    font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text",
                 "Helvetica Neue", "Segoe UI", Inter, sans-serif !important;
    background: linear-gradient(180deg, #fbfbfd 0%, #f5f5f7 100%) !important;
    /* Always use ~3/4 of the viewport, capped at 1600px on huge screens.
       Using width AND max-width ensures the page is wide from first paint
       instead of growing only after content loads. */
    width: min(1600px, 92vw) !important;
    max-width: 1600px !important;
    margin: 0 auto !important;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    color: #1d1d1f !important;
}

/* Cards / panels */
.panel-card {
    background: #ffffff !important;
    border-radius: 18px !important;
    padding: 18px !important;
    box-shadow: 0 1px 2px rgba(0,0,0,0.04), 0 8px 28px rgba(0,0,0,0.05) !important;
    border: 1px solid rgba(0,0,0,0.05) !important;
}

/* Inputs - rounded with apple-blue focus ring */
textarea, input[type="text"], input[type="number"],
.gradio-container .form input,
.gradio-container .form textarea {
    border-radius: 12px !important;
    border: 1px solid #d2d2d7 !important;
    background: #ffffff !important;
    transition: border-color 0.15s ease, box-shadow 0.15s ease !important;
    font-size: 15px !important;
}
textarea:focus, input:focus,
.gradio-container .form input:focus,
.gradio-container .form textarea:focus {
    border-color: #0071e3 !important;
    box-shadow: 0 0 0 4px rgba(0, 113, 227, 0.15) !important;
    outline: none !important;
}

/* Dropdown */
.gradio-container .wrap.svelte-1ipelgc { border-radius: 12px !important; }

/* Block labels */
.gradio-container span[data-testid="block-label"],
.gradio-container .block-label,
.gradio-container label > span {
    color: #6e6e73 !important;
    font-weight: 500 !important;
    font-size: 13px !important;
    letter-spacing: 0.01em;
}

/* Buttons - pill shape, Apple blue. Scoped to the variant classes so it does
   NOT bleed into internal buttons inside dropdowns, accordions, etc. */
.gradio-container button.primary,
.gradio-container button.secondary {
    border-radius: 980px !important;
    font-weight: 500 !important;
    font-size: 15px !important;
    padding: 12px 22px !important;
    transition: transform 0.08s ease, box-shadow 0.18s ease, background 0.18s ease, opacity 0.15s ease !important;
    border: none !important;
    letter-spacing: 0.01em;
}
.gradio-container button.primary {
    background: #0071e3 !important;
    color: #ffffff !important;
    box-shadow: 0 1px 2px rgba(0,113,227,0.25), 0 6px 16px rgba(0,113,227,0.22) !important;
}
.gradio-container button.primary:hover {
    background: #0077ed !important;
    transform: translateY(-1px);
    box-shadow: 0 2px 4px rgba(0,113,227,0.3), 0 10px 22px rgba(0,113,227,0.28) !important;
}
.gradio-container button.primary:active { transform: translateY(0); }
.gradio-container button.secondary {
    background: rgba(0,0,0,0.05) !important;
    color: #1d1d1f !important;
    box-shadow: none !important;
}
.gradio-container button.secondary:hover {
    background: rgba(0,0,0,0.09) !important;
}

/* Make sure the dropdown's selected-value text never gets pill-clipped and
   is properly aligned inside its rounded box. */
.gradio-container .wrap-inner,
.gradio-container .single-select,
.gradio-container .secondary-wrap {
    border-radius: 12px !important;
}
.gradio-container .single-select input,
.gradio-container input[role="listbox"] {
    border-radius: 12px !important;
    padding: 10px 14px !important;
    font-size: 15px !important;
}

/* Status pill */
#status-bar {
    padding: 0 !important;
    margin-top: 6px;
}
.status-pill {
    display: inline-flex;
    align-items: center;
    gap: 9px;
    background: #f5f5f7;
    color: #1d1d1f;
    padding: 10px 14px;
    border-radius: 12px;
    font-size: 13px;
    font-weight: 500;
    line-height: 1;
    border: 1px solid rgba(0,0,0,0.04);
}
.status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: #8e8e93;
    flex-shrink: 0;
}
.status-info .status-dot { background: #8e8e93; }
.status-success { background: rgba(48,209,88,0.10); color: #0a7f2e; border-color: rgba(48,209,88,0.20); }
.status-success .status-dot { background: #30d158; }
.status-error   { background: rgba(255,59,48,0.10); color: #b8261b; border-color: rgba(255,59,48,0.20); }
.status-error   .status-dot { background: #ff3b30; }
.status-running { background: rgba(0,113,227,0.10); color: #0058b8; border-color: rgba(0,113,227,0.20); }
.status-running .status-dot {
    background: #0071e3;
    animation: pulse 1.4s ease-in-out infinite;
}
@keyframes pulse {
    0%, 100% { opacity: 0.4; transform: scale(0.85); }
    50%      { opacity: 1.0; transform: scale(1.15); }
}

/* Image output frame — never crop the image; show full picture with letterbox. */
.image-output {
    border-radius: 18px !important;
    background: #f5f5f7 !important;
}
.image-output,
.image-output > div,
.image-output [data-testid="image"],
.image-output .image-container,
.image-output .image-frame,
.image-output .preview {
    min-height: 440px !important;
    display: flex !important;
    align-items: center !important;
    justify-content: center !important;
}
.image-output img {
    border-radius: 14px !important;
    object-fit: contain !important;
    max-width: 100% !important;
    max-height: 62vh !important;
    width: auto !important;
    height: auto !important;
}

/* Status pill placed inside the right column, above the image. */
.right-status {
    display: flex;
    justify-content: flex-start;
    margin-bottom: 6px;
}

/* Accordion */
.gradio-container details {
    border-radius: 14px !important;
    border: 1px solid rgba(0,0,0,0.06) !important;
    background: #ffffff !important;
}

/* Negative prompt — softer accent so it visually de-emphasises vs. the main prompt */
.negative-prompt textarea {
    background: #fbfbfd !important;
    border-color: #e3e3e8 !important;
}
.negative-prompt textarea:focus {
    background: #ffffff !important;
}

/* Advanced options row — keeps the refine switch + seed input visually paired */
.advanced-row {
    gap: 14px !important;
    margin-top: 2px;
}

/* Refine toggle — iOS-style settings card.
   Goal: title + helper text on the left, a polished pill switch on the right,
   everything contained inside a single soft card so the helper text no longer
   floats orphaned above the box. */
.refine-toggle {
    background: linear-gradient(180deg, #ffffff 0%, #f5f5f7 100%) !important;
    border-radius: 14px !important;
    border: 1px solid rgba(0,0,0,0.06) !important;
    padding: 14px 16px !important;
    box-shadow: 0 1px 2px rgba(0,0,0,0.03) !important;
    transition: border-color 0.18s ease, box-shadow 0.18s ease !important;
    min-height: 88px;
    display: flex !important;
    flex-direction: column !important;
    justify-content: center !important;
}
.refine-toggle:hover {
    border-color: rgba(0,0,0,0.10) !important;
    box-shadow: 0 1px 2px rgba(0,0,0,0.04), 0 4px 14px rgba(0,0,0,0.05) !important;
}

/* Strip default backgrounds from gradio's inner wrappers so only our card shows. */
.refine-toggle .form,
.refine-toggle .wrap,
.refine-toggle .form-wrap,
.refine-toggle > div {
    background: transparent !important;
    border: none !important;
    padding: 0 !important;
    margin: 0 !important;
    box-shadow: none !important;
}

/* Helper / "info" text becomes a proper subtitle UNDER the toggle row. */
.refine-toggle [data-testid="block-info"],
.refine-toggle .info {
    color: #6e6e73 !important;
    font-size: 12px !important;
    line-height: 1.4 !important;
    margin: 8px 0 0 0 !important;
    padding: 0 !important;
    text-align: left !important;
    order: 2 !important;
}

/* Force the gradio wrapper to stack: label-row first, info below. */
.refine-toggle .form,
.refine-toggle > div:not([data-testid="block-info"]):not(.info) {
    display: flex !important;
    flex-direction: column !important;
    align-items: stretch !important;
}

/* Label row: title on the LEFT (full width), toggle pinned to the RIGHT. */
.refine-toggle label {
    display: flex !important;
    align-items: center !important;
    justify-content: space-between !important;
    flex-direction: row-reverse !important;
    cursor: pointer !important;
    margin: 0 !important;
    padding: 0 !important;
    gap: 14px !important;
    width: 100% !important;
    order: 1 !important;
}
.refine-toggle label > span {
    color: #1d1d1f !important;
    font-size: 15px !important;
    font-weight: 600 !important;
    letter-spacing: -0.01em;
    flex: 1 1 auto !important;
    text-align: left !important;
    line-height: 1.3 !important;
}

/* Pill switch — bigger, smoother, more "Apple-like" */
.refine-toggle input[type="checkbox"] {
    appearance: none;
    -webkit-appearance: none;
    width: 46px !important;
    height: 28px !important;
    border-radius: 999px !important;
    background: #e5e5ea !important;
    position: relative;
    cursor: pointer;
    transition: background 0.22s ease, box-shadow 0.22s ease;
    border: none !important;
    flex-shrink: 0 !important;
    margin: 0 !important;
    box-shadow: inset 0 0 1px rgba(0,0,0,0.06);
}
.refine-toggle input[type="checkbox"]::after {
    content: "";
    position: absolute;
    top: 2px;
    left: 2px;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: #ffffff;
    box-shadow: 0 2px 5px rgba(0,0,0,0.18), 0 0 1px rgba(0,0,0,0.05);
    transition: transform 0.24s cubic-bezier(0.4, 0.0, 0.2, 1);
}
.refine-toggle input[type="checkbox"]:hover {
    background: #dcdce0 !important;
}
.refine-toggle input[type="checkbox"]:checked {
    background: #34c759 !important;
}
.refine-toggle input[type="checkbox"]:checked:hover {
    background: #30b352 !important;
}
.refine-toggle input[type="checkbox"]:checked::after {
    transform: translateX(18px);
}
.refine-toggle input[type="checkbox"]:focus-visible {
    box-shadow: 0 0 0 4px rgba(0,113,227,0.20) !important;
}
.refine-toggle input[type="checkbox"]:active::after {
    /* tiny squish on press, very iOS */
    width: 28px;
}
.refine-toggle input[type="checkbox"]:checked:active::after {
    transform: translateX(14px);
}

/* Seed number input — match the prompt/dropdown rounding */
.seed-input input[type="number"] {
    border-radius: 12px !important;
    padding: 10px 14px !important;
    font-variant-numeric: tabular-nums;
}
/* Hide the native spinner buttons on number inputs for a cleaner look */
.seed-input input[type="number"]::-webkit-outer-spin-button,
.seed-input input[type="number"]::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
}
.seed-input input[type="number"] {
    -moz-appearance: textfield;
}
/* Keep the seed column visually aligned with the refine card next to it */
.seed-input {
    align-self: stretch !important;
}

/* Guidance scale slider — Apple-blue track + softer thumb */
.guidance-slider input[type="range"] {
    accent-color: #0071e3 !important;
}
.guidance-slider .head { padding-top: 0 !important; }
.guidance-slider {
    margin-top: 4px;
}

/* Footer tagline */
.tagline {
    text-align: center;
    color: #6e6e73;
    font-size: 12px;
    margin: 18px 0 14px 0;
    font-weight: 400;
}
.tagline a {
    color: #0071e3;
    text-decoration: none;
    font-weight: 500;
    transition: opacity 0.15s ease;
}
.tagline a:hover { opacity: 0.7; }

/* Footer links row (HuggingFace / GitHub / Twitter) */
.footer-links {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 26px;
    flex-wrap: wrap;
    font-size: 13px;
    margin: 24px 0 6px 0;
}
/* When the vivago tagline follows the links row, tighten the gap. */
.footer-links + .tagline {
    margin-top: 4px;
}

/* Hide gradio's default footer for a cleaner look */
footer { display: none !important; }

/* Mobile */
@media (max-width: 640px) {
    .footer-links { gap: 18px; font-size: 12px; }
}
"""


APPLE_THEME = gr.themes.Soft(
    primary_hue=gr.themes.colors.blue,
    neutral_hue=gr.themes.colors.slate,
    radius_size=gr.themes.sizes.radius_lg,
    text_size=gr.themes.sizes.text_md,
    font=[
        gr.themes.GoogleFont("Inter"),
        "ui-sans-serif",
        "-apple-system",
        "BlinkMacSystemFont",
        "Segoe UI",
        "Helvetica Neue",
        "sans-serif",
    ],
).set(
    body_background_fill="*neutral_50",
    block_background_fill="white",
    block_border_width="1px",
    block_label_text_weight="500",
    block_title_text_weight="600",
    button_primary_background_fill="#0071e3",
    button_primary_background_fill_hover="#0077ed",
    button_primary_text_color="white",
    button_primary_border_color="#0071e3",
    button_secondary_background_fill="rgba(0,0,0,0.05)",
    button_secondary_background_fill_hover="rgba(0,0,0,0.09)",
    button_secondary_text_color="#1d1d1f",
    input_background_fill="white",
    input_border_color="#d2d2d7",
    input_border_color_focus="#0071e3",
    input_shadow_focus="0 0 0 4px rgba(0,113,227,0.15)",
)


def _status_html(text: str, kind: str = "info") -> str:
    """Render a styled status pill. kind: info | success | error | running"""
    return (
        f'<div class="status-pill status-{kind}">'
        f'<span class="status-dot"></span>{text}'
        f'</div>'
    )


def _queue_text(waiting: int, running: int) -> str:
    """Inline status text describing the queue from the user's POV.

    Used inside the right-side status pill while THIS user's request is
    sitting in the queue waiting for an open slot.
    """
    if waiting <= 0 and running <= 0:
        return "Queued · waiting for an open slot…"
    parts = []
    if waiting > 0:
        parts.append(f"{waiting} waiting")
    if running > 0:
        parts.append(f"{running} generating")
    return f"In queue · {' · '.join(parts)}"


def _read_queue_stats(demo_obj) -> tuple[int, int, float]:
    """Best-effort read of gradio's internal queue.

    Gradio 5.x structure (gradio/queueing.py):
      demo._queue.event_queue_per_concurrency_id: dict[str, EventQueue]
        EventQueue.queue: list[Event]              ← actually-waiting events
      demo._queue.active_jobs: list[None | list[Event]]
        each slot is None (idle) or a list of currently-processing events.
      demo._queue.process_time_per_fn: dict[BlockFunction, ProcessTime]
        ProcessTime.avg_time: float

    Returns (waiting, running, avg_secs). Each lookup is wrapped in a try
    so the UI degrades gracefully ("idle") if Gradio ever renames a field.
    """
    try:
        q = getattr(demo_obj, "_queue", None)
        if q is None:
            return 0, 0, 0.0

        # ---- Waiting: events sitting in EventQueue.queue ----
        waiting = 0
        events_per_cid = getattr(q, "event_queue_per_concurrency_id", None) or {}
        for ev_q in events_per_cid.values():
            # Newer gradio: ev_q is an EventQueue with a .queue list.
            # Older/alt: ev_q might already be a list. Handle both.
            inner = getattr(ev_q, "queue", ev_q)
            try:
                waiting += len(inner)
            except (TypeError, AttributeError):
                # Last resort: try iterating
                try:
                    waiting += sum(1 for _ in inner)
                except Exception:
                    continue

        # ---- Running: count events held in active_jobs slots ----
        # Each slot is None or a list[Event]; sum the list lengths.
        running = 0
        active = getattr(q, "active_jobs", None) or []
        for slot in active:
            if slot is None:
                continue
            try:
                running += len(slot)
            except (TypeError, AttributeError):
                running += 1  # very old gradio: single Event per slot

        # ---- Average per-run time (best effort across versions) ----
        avg_secs = 0.0
        # Gradio 5.x: dict[BlockFunction, ProcessTime] with .avg_time
        ptpf = getattr(q, "process_time_per_fn", None)
        if isinstance(ptpf, dict) and ptpf:
            try:
                vals = []
                for v in ptpf.values():
                    avg_t = getattr(v, "avg_time", None)
                    if avg_t:
                        vals.append(float(avg_t))
                if vals:
                    avg_secs = sum(vals) / len(vals)
            except Exception:
                avg_secs = 0.0
        # Older: dict[int, float]
        if not avg_secs:
            ptpfi = getattr(q, "process_time_per_fn_index", None)
            if isinstance(ptpfi, dict) and ptpfi:
                try:
                    vals = [float(v) for v in ptpfi.values() if v]
                    if vals:
                        avg_secs = sum(vals) / len(vals)
                except Exception:
                    avg_secs = 0.0
        # Oldest: single float on the queue
        if not avg_secs:
            apt = getattr(q, "avg_process_time", None)
            if apt:
                try:
                    avg_secs = float(apt)
                except Exception:
                    avg_secs = 0.0

        return waiting, running, avg_secs
    except Exception as exc:
        logger.debug(f"Queue introspection failed: {exc}")
        return 0, 0, 0.0


def _fake_generation_iter(prompt: str, wh_ratio_value: str):
    """FAKE_TEST mode generator.

    Mimics the real flow's yield protocol without hitting any external API.
    Useful for exercising the queue UI / status pill locally.

    Yields (image_or_None, status_html) tuples. The very first 'Sending
    request to API…' yield is emitted by the caller, so this iterator picks
    up from 'Request submitted' onwards.
    """
    time.sleep(random.uniform(0.4, 1.0))

    fake_id = f"{random.randint(0, 0xFFFFFFFF):08x}"
    yield None, _status_html(f"Request submitted · Task {fake_id}…", "running")

    target_secs = random.uniform(8.0, 22.0)
    start = time.time()
    while time.time() - start < target_secs:
        elapsed = int(time.time() - start)
        yield None, _status_html(f"Generating… {elapsed}s", "running")
        time.sleep(POLL_INTERVAL)

    yield None, _status_html("Downloading image…", "running")
    time.sleep(0.3)

    rgb = (
        random.randint(40, 220),
        random.randint(40, 220),
        random.randint(40, 220),
    )
    fake_image = Image.new("RGB", (1024, 1024), color=rgb)
    logger.info(f"FAKE_TEST: returning random color image rgb={rgb}, took {target_secs:.1f}s")
    yield fake_image, _status_html("Image generated", "success")


def create_ui():
    logger.info("Creating Gradio UI")
    with gr.Blocks(
        title="HiDream-O1-Image Generator",
        theme=APPLE_THEME,
        css=APPLE_CSS,
    ) as demo:
        # Per-session state used to drive the right-side status pill while
        # this user's request is sitting in the queue. `last_pill_state`
        # caches the most recent pill HTML so the timer can return
        # `gr.update()` (=no-op, no DOM replacement → no flicker) when the
        # queue counts haven't actually changed between ticks.
        queued_state = gr.State(False)
        last_pill_state = gr.State("")

        with gr.Row(equal_height=False):
            with gr.Column(scale=1, elem_classes=["panel-card"]):
                prompt = gr.Textbox(
                    label="Prompt",
                    placeholder="Describe the image you want to create...",
                    lines=5,
                    show_label=True,
                )

                negative_prompt = gr.Textbox(
                    label="Negative Prompt",
                    placeholder="Things you want to avoid in the image (optional)...",
                    lines=2,
                    show_label=True,
                    elem_classes=["negative-prompt"],
                )

                wh_ratio = gr.Dropdown(
                    choices=WH_RATIO_OPTIONS,
                    value=WH_RATIO_OPTIONS[0],
                    label="Aspect Ratio",
                    info="Width : Height",
                )

                guidance_scale = gr.Slider(
                    minimum=1.0,
                    maximum=20.0,
                    step=0.1,
                    value=5.0,
                    label="Guidance Scale",
                    info="Higher values follow the prompt more strictly",
                    elem_classes=["guidance-slider"],
                )

                with gr.Row(elem_classes=["advanced-row"], equal_height=True):
                    enable_prompt_refine = gr.Checkbox(
                        value=True,
                        label="Prompt Refine",
                        info="Let the model rewrite & enrich your prompt",
                        elem_classes=["refine-toggle"],
                        scale=1,
                    )
                    seed = gr.Number(
                        value=-1,
                        label="Seed",
                        info="Use -1 for a random seed",
                        precision=0,
                        minimum=-1,
                        elem_classes=["seed-input"],
                        scale=1,
                    )

                with gr.Row():
                    clear_btn = gr.Button("Clear", variant="secondary", scale=1)
                    generate_btn = gr.Button("Generate", variant="primary", scale=3)

            with gr.Column(scale=1, elem_classes=["panel-card"]):
                status_msg = gr.HTML(
                    value=_status_html("Ready", "info"),
                    elem_id="status-bar",
                    elem_classes=["right-status"],
                )
                output_image = gr.Image(
                    label="Generated Image",
                    format="png",
                    type="pil",
                    interactive=False,
                    show_download_button=True,
                    elem_classes=["image-output"],
                )

        def generate_with_status(
            prompt,
            wh_ratio_value,
            negative_prompt_value,
            enable_prompt_refine_value,
            seed_value,
            guidance_scale_value,
        ):
            logger.info(
                f"Starting image generation with prompt='{(prompt or '')[:50]}...', "
                f"wh_ratio={wh_ratio_value}, "
                f"negative_prompt='{(negative_prompt_value or '')[:30]}...', "
                f"enable_prompt_refine={enable_prompt_refine_value}, "
                f"seed={seed_value}, guidance_scale={guidance_scale_value}"
            )

            yield None, _status_html("Sending request to API…", "running")

            try:
                if not prompt or not prompt.strip():
                    logger.error("Empty prompt provided in UI")
                    yield None, _status_html("Prompt cannot be empty", "error")
                    return

                if wh_ratio_value not in WH_RATIO_OPTIONS:
                    logger.error(f"Invalid aspect ratio selection: {wh_ratio_value}")
                    yield None, _status_html(f"Invalid aspect ratio “{wh_ratio_value}”", "error")
                    return

                try:
                    seed_int = int(seed_value) if seed_value is not None else -1
                except (TypeError, ValueError):
                    seed_int = -1

                try:
                    guidance_scale_f = float(guidance_scale_value) if guidance_scale_value is not None else 5.0
                except (TypeError, ValueError):
                    guidance_scale_f = 5.0

                if FAKE_TEST:
                    logger.info("FAKE_TEST mode active — bypassing real API call")
                    yield from _fake_generation_iter(prompt, wh_ratio_value)
                    return

                logger.info("Creating API request")
                task_id = create_request(
                    prompt,
                    wh_ratio_value,
                    negative_prompt=negative_prompt_value or "",
                    enable_prompt_refine=bool(enable_prompt_refine_value),
                    seed=seed_int,
                    guidance_scale=guidance_scale_f,
                )
                yield None, _status_html(f"Request submitted · Task {task_id[:8]}…", "running")

                start_time = time.time()
                logger.info(f"Starting to poll for results for task ID: {task_id}")

                while time.time() - start_time < MAX_POLL_TIME:
                    elapsed_time = time.time() - start_time
                    logger.debug(
                        f"Polling for results - Task ID: {task_id}, Elapsed: {elapsed_time:.2f}s"
                    )

                    result = get_results(task_id)
                    if not result:
                        time.sleep(POLL_INTERVAL)
                        continue

                    overall_status = result.get("status")
                    sub_results = result.get("sub_task_results", []) or []

                    if overall_status != 1:
                        elapsed = int(time.time() - start_time)
                        yield None, _status_html(f"Generating… {elapsed}s", "running")
                        time.sleep(POLL_INTERVAL)
                        continue

                    if not sub_results:
                        logger.error(f"Task completed but no sub_task_results returned. Task ID: {task_id}")
                        yield None, _status_html("Task completed but no results returned", "error")
                        return

                    sub = sub_results[0]
                    sub_status = sub.get("task_status")

                    if sub_status == 1:
                        logger.info(f"Task completed successfully - Task ID: {task_id}")

                        image_url = sub.get("url")
                        if not image_url:
                            logger.error(f"No image URL in successful response. Sub result: {sub}")
                            yield None, _status_html("No image URL in response", "error")
                            return

                        yield None, _status_html("Downloading image…", "running")

                        logger.info(f"Downloading image - Task ID: {task_id}, URL: {image_url}")
                        image = download_image(image_url)

                        if image:
                            logger.info(f"Image generation complete - Task ID: {task_id}")
                            yield image, _status_html("Image generated", "success")
                            return
                        else:
                            logger.error(f"Failed to download image - Task ID: {task_id}, URL: {image_url}")
                            yield None, _status_html("Failed to download generated image", "error")
                            return

                    elif sub_status == 3:
                        error_msg = sub.get("task_error") or sub.get("message") or "Unknown error"
                        logger.error(
                            f"Task failed - Task ID: {task_id}, Sub status: {sub_status}, Error: {error_msg}"
                        )
                        yield None, _status_html(f"Task failed: {error_msg}", "error")
                        return

                    else:
                        elapsed = int(time.time() - start_time)
                        yield None, _status_html(f"Waiting… {elapsed}s", "running")
                        time.sleep(POLL_INTERVAL)

                logger.error(
                    f"Timeout waiting for task completion - Task ID: {task_id}, Max time: {MAX_POLL_TIME}s"
                )
                yield None, _status_html(f"Timed out after {MAX_POLL_TIME}s", "error")

            except APIError as e:
                logger.error(f"API Error during generation: {str(e)}")
                yield None, _status_html(f"API error: {str(e)}", "error")

            except ValueError as e:
                logger.error(f"Value Error during generation: {str(e)}")
                yield None, _status_html(f"Value error: {str(e)}", "error")

            except Exception as e:
                logger.error(f"Unexpected error during image generation: {str(e)}")
                logger.error(f"Full traceback: {traceback.format_exc()}")
                yield None, _status_html(f"Unexpected error: {str(e)}", "error")

        def _enter_queue():
            """Click handler #1 — runs IMMEDIATELY (queue=False).

            Flips queued_state to True and seeds the pill with a snapshot of
            the current queue. Subsequent live updates come from the timer.
            """
            waiting, running, _ = _read_queue_stats(demo)
            html = _status_html(_queue_text(waiting, running), "running")
            return None, html, True, html

        def _generate_wrapped(
            prompt_value,
            wh_ratio_value,
            negative_prompt_value,
            enable_prompt_refine_value,
            seed_value,
            guidance_scale_value,
        ):
            """Click handler #2 — queued.

            Wraps the existing generator and, on the FIRST yield, also flips
            queued_state to False so the timer stops touching the pill and
            lets the generator's own `yield`s drive it (Generating XXs → ...).
            """
            first = True
            for image, status_html in generate_with_status(
                prompt_value,
                wh_ratio_value,
                negative_prompt_value,
                enable_prompt_refine_value,
                seed_value,
                guidance_scale_value,
            ):
                if first:
                    first = False
                    yield image, status_html, False
                else:
                    yield image, status_html, gr.update()

        generate_btn.click(
            fn=_enter_queue,
            inputs=None,
            outputs=[output_image, status_msg, queued_state, last_pill_state],
            queue=False,
            show_progress="hidden",
        ).then(
            fn=_generate_wrapped,
            inputs=[prompt, wh_ratio, negative_prompt, enable_prompt_refine, seed, guidance_scale],
            outputs=[output_image, status_msg, queued_state],
            show_progress="minimal",
            show_progress_on=[generate_btn],
        )

        def clear_outputs():
            logger.info("Clearing UI outputs")
            return None, _status_html("Ready", "info"), False, ""

        clear_btn.click(
            fn=clear_outputs,
            inputs=None,
            outputs=[output_image, status_msg, queued_state, last_pill_state],
        )

        # Live queue updates inside the right-side pill — only while THIS
        # user is queued. Returns gr.update() (no-op) when nothing changed,
        # which prevents the DOM from being replaced and avoids the pulse
        # animation resetting (= no flicker).
        pill_timer = gr.Timer(value=1.5, active=True)

        def _tick_pill(queued_flag, last_html):
            if not queued_flag:
                return gr.update(), last_html
            waiting, running, _ = _read_queue_stats(demo)
            new_html = _status_html(_queue_text(waiting, running), "running")
            if new_html == last_html:
                return gr.update(), last_html
            return new_html, new_html

        pill_timer.tick(
            fn=_tick_pill,
            inputs=[queued_state, last_pill_state],
            outputs=[status_msg, last_pill_state],
            queue=False,
            show_progress="hidden",
        )

        gr.HTML(
            """
            <div class="tagline footer-links">
                <a href="https://huggingface.co/HiDream-ai/HiDream-O1-Image" target="_blank">HuggingFace</a>
                <a href="https://github.com/HiDream-ai/HiDream-O1-Image" target="_blank">GitHub</a>
                <a href="https://x.com/vivago_ai" target="_blank">Twitter</a>
            </div>
            <div class="tagline">
                For more features and the full experience, visit
                <a href="https://vivago.ai/" target="_blank">vivago.ai</a>.
            </div>
            """
        )

    logger.info("Gradio UI created successfully")
    return demo


if __name__ == "__main__":
    logger.info("Starting HiDream-O1-Image Generator application")
    demo = create_ui()
    logger.info("Launching Gradio interface with queue")
    demo.queue(max_size=50, default_concurrency_limit=4).launch(show_api=False)
    logger.info("Application shutdown")