app.py

"""
Meridian - Historical Image Generator

Takes coordinates and dates, finds historical events, and generates images of those moments.
Built for the Hugging Face MCP Hackathon.
"""

import os
import warnings
from datetime import datetime
from typing import Dict, List, Optional, Tuple

# Suppress FutureWarnings for cleaner logs
warnings.filterwarnings("ignore", category=FutureWarning)

import gradio as gr
from PIL import Image
from huggingface_hub import InferenceClient
import google.generativeai as genai

from services.history_service import (
    build_event_context,
    format_event_digest,
    get_artifacts_for_year,
    get_event_by_name,
    get_event_by_slug,
    get_event_by_qid,
    get_events_by_coordinates,
    get_events_response,
    get_era_vocabulary,
    get_region_context,
    initialize_history,
    search_events_globally,
)

# Import Wikidata service for MCP tools
try:
    from services.wikidata_service import (
        mcp_search_historical_events,
        mcp_get_event_by_qid,
    )
    WIKIDATA_MCP_AVAILABLE = True
except ImportError:
    WIKIDATA_MCP_AVAILABLE = False
from services.prompt_parser import parse_prompt_context, ParsedPrompt


def join_list(items: List[str], conjunction: str = "and") -> str:
    cleaned = [item for item in items if item]
    if not cleaned:
        return ""
    if len(cleaned) == 1:
        return cleaned[0]
    if len(cleaned) == 2:
        return f"{cleaned[0]} {conjunction} {cleaned[1]}"
    return ", ".join(cleaned[:-1]) + f", {conjunction} {cleaned[-1]}"


def describe_time_of_day(hour: Optional[int]) -> str:
    if hour is None:
        return "ambient daylight with balanced, neutral lighting"
    hour = int(hour) % 24
    if 0 <= hour < 4:
        return "pre-dawn darkness punctuated by sparse artificial lights"
    if 4 <= hour < 6:
        return "blue-hour twilight with faint glow along the horizon"
    if 6 <= hour < 10:
        return "soft morning light casting long, gentle shadows"
    if 10 <= hour < 15:
        return "bright midday sunlight with crisp contrast and vivid color"
    if 15 <= hour < 18:
        return "warm late-afternoon sun gilding the scene with golden highlights"
    if 18 <= hour < 20:
        return "dusk with saturated skies and streetlights beginning to glow"
    if 20 <= hour < 23:
        return "nighttime illumination from electric signage and floodlights"
    return "deep night with high-contrast spotlights and reflective surfaces"


def describe_season(latitude: float, month: Optional[int]) -> str:
    if month is None or month < 1 or month > 12:
        return "seasonal atmosphere typical for the region"
    northern = latitude >= 0
    if northern:
        if month in [12, 1, 2]:
            return "winter air with visible breath, bundled clothing, and muted vegetation"
        if month in [3, 4, 5]:
            return "spring freshness with blooming foliage and newly awakened colors"
        if month in [6, 7, 8]:
            return "summer warmth with lush greenery and vibrant skylines"
        return "autumn chill with turning leaves and cool breezes"
    else:
        if month in [12, 1, 2]:
            return "southern hemisphere summer with bright skies and humid air"
        if month in [3, 4, 5]:
            return "autumn hues with cooling evenings and amber light"
        if month in [6, 7, 8]:
            return "winter clarity with crisp air and softer daylight"
        return "spring renewal with emerging blossoms and mild winds"


def add_composition_cues(mood: str, event_type: str = "") -> str:
    """Returns composition cues for the selected style."""
    composition_map = {
        "Documentary": "wide angle view, documentary photography style, centered composition",
        "Dramatic": "dramatic perspective, cinematic framing, rule of thirds, leading lines",
        "Artistic": "artistic composition, balanced framing, visual depth",
        "Cinematic": "cinematic wide shot, dramatic shadows, foreground action, background architecture",
        "Photojournalistic": "photojournalistic style, candid framing, natural lighting",
        "Cartoon": "animated style, vibrant colors, cartoon illustration, bold outlines",
        "Minecraft": "blocky pixelated style, minecraft aesthetic, cubic forms, voxel art",
        "Retro": "vintage photography style, retro color grading, film grain, nostalgic atmosphere",
        "Glitch": "digital glitch art, motion blur effects, halftone dot patterns, RGB channel separation, pixelated distortion, cyberpunk aesthetic, data corruption visual effects",
    }
    
    base_cue = composition_map.get(mood, "wide angle view, cinematic framing")
    
    # Only add depth cues for photorealistic styles
    if mood in ["Documentary", "Cinematic", "Dramatic", "Photojournalistic", "Artistic"]:
        depth_cues = "foreground action, middle ground figures, background architecture, atmospheric depth"
        return f"{base_cue}, {depth_cues}"
    
    return base_cue


def build_event_sections(
    event: dict,
    time_desc: str,
    season_desc: str,
    mood: str,
    lat: float,
    lon: float,
    year: int,
) -> Dict[str, str]:
    """Build VISUAL-FIRST event description for image generation.

    Returns concrete visual elements that image models understand.
    Target: 35-50 words for base prompt (style adds 15-20 more).
    """

    event_name = event.get("name", "Historical scene")
    event_year = event.get("year", year)
    location = get_location_name(event, lat, lon)

    # VISUAL SUBJECT (what the image shows)
    subject_type = "historical scene"
    if "battle" in event_name.lower() or "war" in event_name.lower():
        subject_type = "battlefield"
    elif "signing" in event_name.lower() or "declaration" in event_name.lower():
        subject_type = "formal ceremony"
    elif "speech" in event_name.lower() or "address" in event_name.lower():
        subject_type = "public gathering"
    elif "fall" in event_name.lower() or "liberation" in event_name.lower():
        subject_type = "crowd scene"

    # PARTICIPANTS (who's in the image with period clothing)
    actors = event.get("actors") or []
    participants_desc = ""
    if actors:
        # Add period-specific clothing descriptors
        clothing = get_period_clothing(event_year)
        if len(actors) == 1:
            participants_desc = f"{actors[0]} in {clothing}"
        elif len(actors) == 2:
            participants_desc = f"{actors[0]} and {actors[1]} in {clothing}"
        else:
            participants_desc = f"{actors[0]}, {actors[1]}, and others in {clothing}"

    # ENVIRONMENT (where the scene takes place)
    location_desc = get_environment_description(location, event_name, event_year)

    # VISUAL ELEMENTS (period artifacts, architecture)
    artifacts = event.get("artifacts") or []
    visual_elements = join_list(artifacts[:3], "and") if artifacts else ""

    # LIGHTING (time-based atmospheric description)
    lighting = time_desc  # Use full description

    return {
        "subject": subject_type,
        "participants": participants_desc,
        "location": location_desc,
        "elements": visual_elements,
        "lighting": lighting,
        "event_name": event_name,  # Keep for fallback
    }


def get_period_clothing(year: int) -> str:
    """Get period-appropriate clothing description."""
    if year < 1500:
        return "medieval robes and tunics"
    elif year < 1700:
        return "Renaissance doublets and robes"
    elif year < 1800:
        return "18th century coats and breeches"
    elif year < 1850:
        return "early 19th century military uniforms"
    elif year < 1900:
        return "Victorian formal attire"
    elif year < 1920:
        return "Edwardian formal dress"
    elif year < 1950:
        return "1940s military uniforms"
    elif year < 1980:
        return "mid-century formal wear"
    else:
        return "modern formal attire"


def get_environment_description(location: str, event_name: str, year: int) -> str:
    """Get concrete environmental description."""
    if "°" in location:
        env_name = ""
    else:
        env_name = location

    if "battle" in event_name.lower() or "war" in event_name.lower():
        if year < 1900:
            return f"{env_name} countryside with period cannons, military encampments, and smoke from musket fire" if env_name else "muddy battlefield with period cannons, military encampments, and gunpowder smoke"
        else:
            return f"{env_name} terrain with military vehicles, fortifications, and artillery" if env_name else "war-torn terrain with military vehicles, fortifications, and artillery smoke"
    elif "palace" in location.lower() or "hall" in event_name.lower():
        return "grand ornate interior with period chandeliers, decorative architecture, and formal furnishings"
    elif "street" in event_name.lower() or "crowd" in event_name.lower() or "fall" in event_name.lower():
        return f"{env_name} streets with period buildings, gathered crowds, and urban architecture" if env_name else "city streets with period buildings, gathered crowds, and architectural details"
    else:
        return f"{env_name} with historically accurate period architecture and setting" if env_name else "period-accurate setting with appropriate historical architecture"


def assemble_prompt_from_sections(sections: Dict[str, str], quality: str) -> str:
    """Assemble VISUAL-FIRST prompt for image generation.

    Format: "[Subject] showing [participants]. [Environment with elements]. [Lighting]."
    NO metadata - only visual descriptions that models understand.
    """

    subject = sections.get("subject", "historical scene")
    participants = sections.get("participants", "")
    location = sections.get("location", "")
    elements = sections.get("elements", "")
    lighting = sections.get("lighting", "")

    # Build prompt sentence by sentence
    parts = []

    # Sentence 1: Subject + Participants
    if participants:
        parts.append(f"{subject.capitalize()} showing {participants}")
    else:
        event_name = sections.get("event_name", "historical event")
        parts.append(f"{subject.capitalize()} depicting {event_name}")

    # Sentence 2: Environment WITH Elements (combined)
    if location and elements:
        parts.append(f"{location} with {elements}")
    elif location:
        parts.append(location)
    elif elements:
        parts.append(f"Scene with {elements}")

    # Sentence 3: Lighting/Atmosphere
    if lighting:
        parts.append(f"{lighting}")

    # Join all parts with periods for clear structure
    final = ". ".join(parts)

    return final.strip()


def build_fallback_prompt(
    lat: float,
    lon: float,
    year: int,
    month: int,
    day: int,
    hour: int,
    mood: str,
) -> Tuple[str, str]:
    time_desc = describe_time_of_day(hour)
    season_desc = describe_season(lat, month)
    vocab = get_era_vocabulary(year)
    artifact_titles = [artifact["title"] for artifact in get_artifacts_for_year(year, limit=3)]
    sections = {
        "scene": f"{mood} depiction of daily life near {lat:.2f}, {lon:.2f} in {year}.",
        "participants": "Participants include residents, traders, and travelers in their everyday routines.",
        "environment": (
            f"Environment frames {vocab.get('architecture')} under {time_desc} and {season_desc}."
        ),
        "elements": (
            f"Visible elements: {join_list(artifact_titles)}."
            if artifact_titles
            else f"Technology of the era includes {vocab.get('technology')} and {vocab.get('transport')}."
        ),
    }
    # Style-appropriate quality tags
    if mood in ["Cartoon", "Minecraft", "Retro", "Glitch"]:
        quality_map = {
            "Cartoon": "cartoon illustration style, vibrant colors, bold outlines, historically inspired",
            "Minecraft": "minecraft blocky style, pixelated, cubic forms, historically themed",
            "Retro": "retro vintage style, film grain, nostalgic color grading, historically accurate",
            "Glitch": "digital glitch art style, cyberpunk aesthetic, data corruption effects, historically themed"
        }
        quality = quality_map.get(mood, f"{mood} style, historically inspired")
    else:
        quality = f"{mood} style, historically accurate, photorealistic, 8K"
    prompt = assemble_prompt_from_sections(sections, quality)
    hint = (
        f"📍 {lat:.4f}, {lon:.4f} | 📅 {year}-{month:02d}-{day:02d} {hour:02d}:00\n"
        "ℹ️ No curated event match found; using era vocabulary fallback."
    )
    return prompt, hint

# Load environment variables
try:
    from dotenv import load_dotenv
    load_dotenv()
except ImportError:
    pass

# ==========================
# SSL Certificate Fix
# ==========================
# Fix SSL certificate issues on macOS/Anaconda
try:
    import certifi
    cert_path = certifi.where()
    if cert_path and os.path.exists(cert_path):
        os.environ.setdefault("SSL_CERT_FILE", cert_path)
        os.environ.setdefault("REQUESTS_CA_BUNDLE", cert_path)
        os.environ.setdefault("CURL_CA_BUNDLE", cert_path)
except ImportError:
    pass

# ==========================
# Configuration
# ==========================

# Try both common environment variable names for HF token
HF_TOKEN = (os.getenv("HUGGINGFACE_API_TOKEN") or os.getenv("HF_TOKEN", "")).strip()
GEMINI_API_KEY = os.getenv("GEMINI_API_KEY", "").strip()

# Display token status on startup
print("\n" + "="*60)
print("🔑 API Token Status:")
print("="*60)
if HF_TOKEN:
    print(f"✅ HF_TOKEN: Found ({len(HF_TOKEN)} chars) - {HF_TOKEN[:10]}...")
else:
    print("❌ HF_TOKEN: Not found!")
    print("   Set HUGGINGFACE_API_TOKEN or HF_TOKEN environment variable")

if GEMINI_API_KEY:
    print(f"✅ GEMINI_API_KEY: Found ({len(GEMINI_API_KEY)} chars) - {GEMINI_API_KEY[:10]}...")
    genai.configure(api_key=GEMINI_API_KEY)
else:
    print("⚠️  GEMINI_API_KEY: Not found (prompts will use fallback)")
print("="*60 + "\n")

# Image generation models
IMAGE_MODELS = {
    "FLUX.1-dev (High Quality)": "black-forest-labs/FLUX.1-dev",
    "FLUX.1-schnell (Fast)": "black-forest-labs/FLUX.1-schnell",
}

# ==========================
# Negative Prompts by Era (Prevent Anachronisms)
# ==========================

NEGATIVE_PROMPTS_BY_ERA = {
    (-5000, 500): "modern clothing, eyeglasses, wristwatches, cars, trains, airplanes, electric lights, smartphones, cameras, plastic, metal zippers, sneakers, jeans, t-shirts, hoodies, sunglasses, baseball caps, medieval armor, Renaissance art style",
    (500, 1500): "Renaissance art style, modern clothing, eyeglasses, wristwatches, cars, trains, airplanes, electric lights, smartphones, cameras, plastic, metal zippers, sneakers, jeans, t-shirts, hoodies, sunglasses, baseball caps, printing press, gunpowder weapons",
    (1500, 1800): "cars, motorcycles, airplanes, electric lights, smartphones, modern electronics, plastic materials, synthetic fabrics, LED screens, digital devices, neon signs, concrete buildings, steel skyscrapers, industrial machinery",
    (1800, 1900): "cars, motorcycles, airplanes, electric lights, smartphones, modern electronics, plastic materials, synthetic fabrics, LED screens, digital devices, neon signs, concrete buildings, steel skyscrapers, modern vehicles",
    (1900, 1940): "smartphones, laptops, computers, LED lights, jet aircraft, modern cars (post-1940), plastic bottles, digital screens, television, contemporary architecture, synthetic clothing, polyester, atomic age technology",
    (1940, 1970): "smartphones, tablets, computers, personal electronics, LED billboards, 1980s fashion, digital displays, modern vehicles (post-1970), synthesizers, disco fashion, platform shoes, personal computers",
    (1970, 2000): "smartphones, tablets, laptops, modern electronics (post-2000), contemporary fashion, LED screens, modern architecture (post-2000), flat screen monitors, wireless devices, social media",
    (2000, 2100): "futuristic technology, holograms, flying cars, sci-fi elements, unrealistic technology, augmented reality interfaces, cyberpunk aesthetics, AI robots"
}

# FLUX-specific negative prompts (always included)
FLUX_NEGATIVE_BASE = "cartoon, illustration, painting, drawing, sketch, low quality, blurry, distorted, watermark, text, signature, jpeg artifacts, pixelated, bad anatomy, deformed, ugly, duplicate, morbid, mutilated, extra fingers, mutated hands, poorly drawn hands, poorly drawn face, mutation, deformed, bad proportions, extra limbs, cloned face, disfigured, gross proportions, malformed limbs, missing arms, missing legs, extra arms, extra legs, fused fingers, too many fingers, long neck"

def get_negative_prompt(year: int) -> str:
    """Returns negative prompt to prevent anachronisms for the given year."""
    era_negatives = ""
    for (start, end), negatives in NEGATIVE_PROMPTS_BY_ERA.items():
        if start <= year < end:
            era_negatives = negatives
            break
    if not era_negatives:
        era_negatives = NEGATIVE_PROMPTS_BY_ERA[(1970, 2000)]  # Default
    
    # Combine era-specific and FLUX base negatives
    return f"{FLUX_NEGATIVE_BASE}, {era_negatives}"

# ==========================
# AI Prompt Generation
# ==========================

def generate_historical_prompt(
    lat: float,
    lon: float,
    year: int,
    month: int,
    day: int,
    hour: int,
    mood: str = "Documentary",
) -> Tuple[str, str]:
    """Finds historical events and builds a prompt for image generation."""

    # Find events near the coordinates, prioritizing exact year matches
    events = get_events_by_coordinates(
        lat, lon, year,
        radius_km=400,
        limit=4,
        include_wikidata=True,
        year_weight=1.5,
    )
    time_desc = describe_time_of_day(hour)
    season_desc = describe_season(lat, month)

    if events:
        focus_event = events[0]
        sections = build_event_sections(focus_event, time_desc, season_desc, mood, lat, lon, year)
        # Style-appropriate quality tags
        if mood in ["Cartoon", "Minecraft", "Retro", "Glitch"]:
            quality_map = {
                "Cartoon": "cartoon illustration style, vibrant colors, bold outlines, historically inspired",
                "Minecraft": "minecraft blocky style, pixelated, cubic forms, historically themed",
                "Retro": "retro vintage style, film grain, nostalgic color grading, historically accurate",
                "Glitch": "digital glitch art style, cyberpunk aesthetic, data corruption effects, historically themed"
            }
            quality = quality_map.get(mood, f"{mood} style, historically inspired")
        else:
            quality = f"{mood} style, historically accurate, photorealistic, 8K"
        prompt = assemble_prompt_from_sections(sections, quality)

        # Show where the event came from
        source = focus_event.get("source", "curated")
        source_badge = "📚 Curated" if source == "curated" else "🌐 Wikidata"
        qid = focus_event.get("qid", "")
        source_info = f"{source_badge}"
        if qid:
            source_info += f" ({qid})"
        
        # Show how close the year match is
        year_delta = focus_event.get("year_delta", 0)
        if year_delta == 0:
            year_match = "🎯 Exact year match!"
        elif year_delta <= 2:
            year_match = f"📅 ±{year_delta} year(s)"
        elif year_delta <= 5:
            year_match = f"📅 ~{year_delta} years"
        elif year_delta <= 10:
            year_match = f"📅 ~{year_delta} years apart"
        else:
            year_match = f"⚠️ {year_delta} years apart"

        hint_lines = [
            f"📍 {lat:.4f}, {lon:.4f} | 📅 {year}-{month:02d}-{day:02d} {hour:02d}:00",
            (
                f"🎯 Focus event: {focus_event['name']} ({focus_event.get('year')}) · "
                f"{focus_event.get('distance_km')}km · {year_match} · {source_info}"
            ),
        ]
        summary = focus_event.get("summary") or focus_event.get("narrative") or focus_event.get("description")
        if summary:
            hint_lines.append(f"📝 {summary[:200]}{'...' if len(summary) > 200 else ''}")
        
        # Show participants if available
        participants = focus_event.get("actors") or focus_event.get("participants") or []
        if participants:
            hint_lines.append(f"👥 Participants: {', '.join(participants[:5])}")
        
        if len(events) > 1:
            hint_lines.append("📚 Related possibilities:")
            for related in events[1:]:
                rel_source = "📚" if related.get("source") == "curated" else "🌐"
                hint_lines.append(
                    f"- {rel_source} {related['name']} ({related.get('year')}) · {related.get('distance_km')}km · "
                    f"conf {related.get('match_confidence', 0):.2f}"
                )
        hint = "\n".join(hint_lines)
        return prompt, hint

    # Fallback when no curated event is close enough
    return build_fallback_prompt(lat, lon, year, month, day, hour, mood)

# ==========================
# Image Generation
# ==========================

def generate_image(prompt: str, model_key: str, year: int = None, negative_prompt: str = None) -> Tuple[Optional[Image.Image], str]:
    """Generates image using FLUX via Hugging Face API. Auto-generates negative prompts based on year if not provided."""
    
    if not HF_TOKEN:
        error_msg = """❌ Hugging Face API token not configured!

Please set one of these environment variables:
• HUGGINGFACE_API_TOKEN='your_token_here'
• HF_TOKEN='your_token_here'

Get your token at: https://huggingface.co/settings/tokens"""
        return None, error_msg
    
    model_id = IMAGE_MODELS.get(model_key, IMAGE_MODELS["FLUX.1-dev (High Quality)"])
    
    # Generate negative prompt if not provided and year is available
    if negative_prompt is None and year is not None:
        negative_prompt = get_negative_prompt(year)
    
    try:
        client = InferenceClient(token=HF_TOKEN)
        
        start_time = datetime.now()
        
        # Build parameters
        params = {
            "prompt": prompt,
            "model": model_id,
            "width": 1024,
            "height": 768,
        }
        
        # Add negative prompt if available (FLUX supports it)
        if negative_prompt:
            params["negative_prompt"] = negative_prompt
        
        image = client.text_to_image(**params)
        elapsed = (datetime.now() - start_time).total_seconds()
        
        status = f"✅ Generated in {elapsed:.1f}s using {model_key}"
        if negative_prompt:
            status += " (with era-appropriate exclusions)"
        return image, status

    except Exception as e:
        error_msg = f"❌ Generation failed: {str(e)}"
        # Add helpful context for common errors
        if "rate limit" in str(e).lower():
            error_msg += "\n\n💡 Tip: Try FLUX.1-schnell (faster) or wait a few minutes."
        elif "timeout" in str(e).lower():
            error_msg += "\n\n💡 Tip: Model loading. Try again in 30 seconds."
        return None, error_msg

# ==========================
# Main Workflow
# ==========================

def process_coordinates(lat: float, lon: float, year: int, month: int, day: int, hour: int, mood: str, model_key: str, custom_prompt: str = None):
    """Main workflow: takes coordinates and date, generates prompt and image."""
    
    # Generate prompt or use custom one
    status_parts = []
    if custom_prompt and custom_prompt.strip():
        prompt = custom_prompt.strip()
        hint = f"📍 {lat:.4f}, {lon:.4f} | 📅 {year}-{month:02d}-{day:02d} {hour}:00 (Custom prompt)"
        status_parts.append("✅ Using custom prompt")
    else:
        status_parts.append("🔍 Searching historical events...")
        prompt, hint = generate_historical_prompt(lat, lon, year, month, day, hour, mood)
        status_parts.append("✅ Prompt generated")
    
    # Generate the image
    status_parts.append(f"🎨 Generating image with {model_key}...")
    image, gen_status = generate_image(prompt, model_key, year=year)
    status_parts.append(gen_status)
    
    # Build timeline of nearby events
    status_parts.append("📚 Building historical timeline...")
    events = get_events_by_coordinates(
        lat, lon, year,
        radius_km=500,
        limit=5,
        include_wikidata=True,
        year_weight=1.5,
    )
    status_parts.append(f"✅ Found {len(events)} nearby events")
    
    status = " | ".join(status_parts)
    
    timeline_md = "### Nearby Historical Events\n\n"
    if events:
        for event in events:
            source = event.get("source", "curated")
            source_icon = "📚" if source == "curated" else "🌐"
            qid = event.get("qid", "")
            qid_link = f" [[{qid}](https://www.wikidata.org/wiki/{qid})]" if qid else ""
            
            # Year match indicator
            year_delta = event.get("year_delta", 0)
            if year_delta == 0:
                year_badge = "🎯"
            elif year_delta <= 5:
                year_badge = "📅"
            else:
                year_badge = "⏳"

            timeline_md += (
                f"**{event.get('year')}** {year_badge} — {source_icon} {event.get('name')}{qid_link} "
                f"({event.get('distance_km')}km"
            )
            if year_delta > 0:
                timeline_md += f" · ±{year_delta}yr"
            timeline_md += f")\n\n"
            
            summary = event.get("summary") or event.get("narrative") or event.get("description")
            if summary:
                timeline_md += f"> {summary[:180]}{'...' if len(summary) > 180 else ''}\n\n"
            
            # Show participants for Wikidata events
            participants = event.get("actors") or event.get("participants") or []
            if participants and source == "wikidata":
                timeline_md += f"_Participants: {', '.join(participants[:4])}_\n\n"
        else:
            timeline_md += "_No specific events found in database or Wikidata. Scene generated from era-appropriate context._"
    
    return image, prompt, hint, status, timeline_md

# ==========================
# Gradio UI
# ==========================

def create_app():
    """Sets up the Gradio UI."""
    
    # Initialize history dataset and store
    initialize_history()
    
    # Hybrid Theme: Warm Hero + Clean Readable Content
    # Hero uses Peach/Lavender/Sky Blue gradient
    # Content areas use high-contrast, professional styling
    custom_css = """
    :root {
        /* Hero colors (warm palette) */
        --peach: #ffad7a;
        --peach-dark: #e8935c;
        --lavender: #b8a9d9;
        --sky-blue: #7ACCFF;
        
        /* Content colors (high contrast, professional) */
        --bg-light: #f9fafb;
        --surface: #ffffff;
        --text-primary: #1f2937;
        --text-secondary: #4b5563;
        --text-muted: #6b7280;
        --border-default: #e5e7eb;
        --border-subtle: #f3f4f6;
        
        /* Accent (peach for interactive elements) */
        --accent: #ffad7a;
        --accent-hover: #e8935c;
        --accent-subtle: rgba(255, 173, 122, 0.1);

        /* Shadows */
        --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
        --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
        --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
    }
    
    /* Base - Clean, readable */
    body {
        background: var(--bg-light) !important;
        color: var(--text-primary) !important;
        font-family: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Segoe UI', Roboto, sans-serif !important;
        -webkit-font-smoothing: antialiased;
    }

    .gradio-container {
        max-width: 100% !important;
        background: var(--bg-light) !important;
    }
    
    /* ========== HERO - Warm gradient (kept from new design) ========== */
    .hero {
        text-align: center;
        padding: 2.5rem 2rem;
        background: linear-gradient(135deg, var(--peach) 0%, var(--lavender) 50%, var(--sky-blue) 100%);
        border-radius: 20px;
        margin: 1rem;
        box-shadow: var(--shadow-lg), 0 0 30px rgba(255, 173, 122, 0.2);
        position: relative;
        overflow: hidden;
    }
    
    .hero::before {
        content: '';
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: radial-gradient(ellipse at 30% 20%, rgba(255,255,255,0.35) 0%, transparent 50%);
        pointer-events: none;
    }
    
    .hero h1 {
        font-size: 2.75rem;
        font-weight: 600;
        color: #ffffff !important;
        margin-bottom: 0.5rem;
        text-shadow: 0 2px 8px rgba(0,0,0,0.15);
        letter-spacing: -0.03em;
        position: relative;
        font-family: 'Inter', 'Helvetica Neue', system-ui, sans-serif;
    }
    
    .hero p {
        color: rgba(255, 255, 255, 0.95);
        font-size: 1.1rem;
        font-weight: 450;
        position: relative;
    }
    
    /* ========== CONTENT AREAS - Clean, high contrast ========== */
    
    /* Layout */
    .main-grid {
        display: grid;
        grid-template-columns: 320px 1fr;
        gap: 1.5rem;
        padding: 1rem;
    }
    
    /* Sidebar - Clean white */
    .sidebar {
        background: var(--surface);
        border-radius: 12px;
        padding: 1.5rem;
        border: 1px solid var(--border-default);
        box-shadow: var(--shadow-md);
        height: fit-content;
        position: sticky;
        top: 1rem;
    }
    
    /* Main Panel - Clean white */
    .main-panel {
        background: var(--surface);
        border-radius: 12px;
        padding: 1.5rem;
        border: 1px solid var(--border-default);
        box-shadow: var(--shadow-md);
    }
    
    /* Inputs - Clean with peach focus */
    input, select, textarea {
        background: var(--bg-light) !important;
        border: 1px solid var(--border-default) !important;
        color: var(--text-primary) !important;
        border-radius: 8px !important;
        transition: all 0.15s ease !important;
    }
    
    input:focus, select:focus, textarea:focus {
        border-color: var(--accent) !important;
        box-shadow: 0 0 0 3px var(--accent-subtle) !important;
        outline: none !important;
    }
    
    /* Buttons - Peach gradient (elegant touch) */
    button {
        background: linear-gradient(135deg, var(--accent) 0%, var(--accent-hover) 100%) !important;
        color: #ffffff !important;
        font-weight: 600 !important;
        border: none !important;
        border-radius: 10px !important;
        padding: 0.75rem 1.5rem !important;
        transition: all 0.2s ease !important;
        box-shadow: 0 2px 8px rgba(255, 173, 122, 0.3) !important;
    }
    
    button:hover {
        background: linear-gradient(135deg, var(--accent-hover) 0%, #d67d45 100%) !important;
        transform: translateY(-1px) !important;
        box-shadow: 0 4px 16px rgba(255, 173, 122, 0.4) !important;
    }
    
    /* Labels - High contrast */
    label {
        color: var(--text-secondary) !important;
        font-weight: 500 !important;
        font-size: 0.875rem !important;
    }
    
    /* Section headers - Clear hierarchy */
    .markdown-text h3, h3 {
        color: var(--text-primary) !important;
        font-weight: 600 !important;
        font-size: 1rem !important;
        margin-bottom: 0.5rem !important;
    }
    
    /* All markdown text - Ensure readability */
    .markdown-text, .markdown-text p, .markdown-text span {
        color: var(--text-primary) !important;
    }
    
    .markdown-text strong {
        color: var(--text-primary) !important;
        font-weight: 600 !important;
    }
    
    /* Image container - Enhanced with animations */
    .gr-image {
        border-radius: 12px !important;
        border: 1px solid var(--border-default) !important;
        box-shadow: var(--shadow-md) !important;
        transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1) !important;
        opacity: 0;
        animation: fadeInImage 0.6s ease-out forwards !important;
    }
    
    @keyframes fadeInImage {
        from {
            opacity: 0;
            transform: translateY(10px) scale(0.98);
        }
        to {
            opacity: 1;
            transform: translateY(0) scale(1);
        }
    }
    
    .gr-image:hover {
        border-color: var(--accent) !important;
        box-shadow: 0 8px 24px rgba(255, 173, 122, 0.3) !important;
        transform: translateY(-2px) scale(1.01) !important;
    }
    
    /* Hint/status text - Subtle background, readable text with smooth transitions */
    .hint-text {
        font-size: 0.9rem;
        color: var(--text-secondary);
        padding: 0.875rem 1rem;
        background: var(--bg-light);
        border-radius: 8px;
        border: 1px solid var(--border-default);
        margin-top: 0.5rem;
        line-height: 1.6;
        transition: all 0.3s ease !important;
        animation: slideInHint 0.4s ease-out !important;
    }
    
    @keyframes slideInHint {
        from {
            opacity: 0;
            transform: translateX(-10px);
        }
        to {
            opacity: 1;
            transform: translateX(0);
        }
    }
    
    /* Accordion */
    .gr-accordion {
        background: var(--surface) !important;
        border: 1px solid var(--border-default) !important;
        border-radius: 8px !important;
    }
    
    /* Blockquotes - Subtle lavender touch */
    blockquote, .markdown-text blockquote {
        border-left: 3px solid var(--lavender) !important;
        background: #faf9fc !important;
        padding: 0.75rem 1rem !important;
        margin: 0.5rem 0 !important;
        border-radius: 0 6px 6px 0 !important;
        color: var(--text-secondary) !important;
    }
    
    /* Links - Sky blue */
    a {
        color: #2563eb !important;
        text-decoration: none !important;
    }
    
    a:hover {
        color: var(--accent-hover) !important;
        text-decoration: underline !important;
    }
    
    /* Slider */
    input[type="range"] {
        accent-color: var(--accent) !important;
    }
    
    /* Loading states - Enhanced */
    .generating {
        position: relative;
        overflow: hidden;
    }

    .generating::after {
        content: '';
        position: absolute;
        top: 0;
        left: -100%;
        width: 100%;
        height: 100%;
        background: linear-gradient(90deg, transparent, rgba(255,173,122,0.2), transparent);
        animation: loading 1.5s infinite;
    }

    @keyframes loading {
        0% { left: -100%; }
        100% { left: 100%; }
    }

    /* Skeleton loader for image placeholder */
    .image-skeleton {
        width: 100%;
        height: 600px;
        background: linear-gradient(90deg, 
            var(--bg-light) 0%, 
            var(--border-subtle) 50%, 
            var(--bg-light) 100%);
        background-size: 200% 100%;
        border-radius: 12px;
        animation: skeleton-loading 1.5s ease-in-out infinite;
    }

    @keyframes skeleton-loading {
        0% { background-position: 200% 0; }
        100% { background-position: -200% 0; }
    }

    /* Progress indicator */
    .progress-bar {
        height: 4px;
        background: linear-gradient(90deg, var(--accent), var(--lavender));
        border-radius: 2px;
        animation: progress 2s ease-in-out infinite;
        margin: 1rem 0;
    }

    @keyframes progress {
        0%, 100% { transform: scaleX(0.3); transform-origin: left; }
        50% { transform: scaleX(1); transform-origin: left; }
    }

    /* Status text with pulse animation */
    .status-generating {
        color: var(--accent) !important;
        font-weight: 500 !important;
        animation: pulse 2s ease-in-out infinite !important;
    }

    @keyframes pulse {
        0%, 100% { opacity: 1; }
        50% { opacity: 0.7; }
    }

    /* Button active state */
    button:active {
        transform: translateY(0) scale(0.98) !important;
        transition: transform 0.1s ease !important;
    }

    /* Panel entrance animation */
    .main-panel, .sidebar {
        animation: fadeInPanel 0.5s ease-out !important;
    }

    @keyframes fadeInPanel {
        from {
            opacity: 0;
            transform: translateY(20px);
        }
        to {
            opacity: 1;
            transform: translateY(0);
        }
    }

    /* Smooth text transitions */
    .markdown-text {
        transition: opacity 0.3s ease !important;
    }

    /* Footer */
    footer {
        display: none !important;
    }

    /* Responsive */
    @media (max-width: 768px) {
        .main-grid {
            grid-template-columns: 1fr;
        }
        
        .sidebar {
            position: static;
        }
        
        .hero h1 {
            font-size: 2rem;
            color: #ffffff !important;
        }
    }
    """
    
    with gr.Blocks(title="Meridian — Historical Image Generator") as demo:
        # Inject custom CSS
        gr.HTML(f"<style>{custom_css}</style>")
        
        # Hero
        gr.HTML("""
        <div class="hero">
            <h1>🌍 Meridian</h1>
            <p>Generate historically accurate scenes from geospatial coordinates and date/time inputs</p>
        </div>
        """)

        with gr.Row(elem_classes="main-grid"):
            
            # Left Sidebar: Inputs
            with gr.Column(scale=1, elem_classes="sidebar"):
                gr.Markdown("### ✍️ Custom Prompt")
                prompt_override = gr.Textbox(
                    label="Describe the scene (optional)",
                    placeholder="Create an image at 31.7785° N, 35.2296° E, April 3, 33 CE, 15:00 hours",
                            lines=4,
                )
                gr.Markdown("_When filled, coordinate inputs are locked so the prompt takes precedence._")

                gr.Markdown("### 📍 Coordinates")
                latitude = gr.Number(label="Latitude", value=52.5163, step=0.0001)
                longitude = gr.Number(label="Longitude", value=13.3777, step=0.0001)
                
                gr.Markdown("### 📅 Date & Time")
                year = gr.Number(label="Year", value=1989, precision=0)
                month = gr.Number(label="Month (1-12)", value=11, precision=0, minimum=1, maximum=12)
                day = gr.Number(label="Day (1-31)", value=9, precision=0, minimum=1, maximum=31)
                hour = gr.Slider(label="Hour (0-23)", minimum=0, maximum=23, value=23, step=1)
                
                gr.Markdown("### 🎨 Style")
                mood = gr.Dropdown(
                    label="Mood/Style",
                    choices=["Documentary", "Cinematic", "Photojournalistic", "Dramatic", "Cartoon", "Minecraft", "Retro", "Glitch"],
                    value="Documentary"
                )
                
                model_choice = gr.Dropdown(
                    label="Model",
                    choices=list(IMAGE_MODELS.keys()),
                    value="FLUX.1-dev (High Quality)"
                )
                
                generate_btn = gr.Button("🎬 Generate Image", variant="primary", size="lg")
            
            # Right Main Panel: Outputs
            with gr.Column(scale=3, elem_classes="main-panel"):
                
                hint_display = gr.Markdown(
                    "Enter coordinates and date/time *or* supply a custom prompt, then click Generate.",
                    elem_classes="hint-text",
                )
                
                gr.Markdown("### 📝 Scene Description")
                gr.Markdown("_Generated prompt (appears after image generation, editable for regeneration):_")
                prompt_box = gr.Textbox(
                    label="",
                    lines=6,
                    placeholder="Prompt will appear here after generation. You can edit it and regenerate.",
                    show_label=False
                )
                
                gr.Markdown("### 🖼️ Generated Image")
                image_output = gr.Image(
                    label="",
                    show_label=False,
                    height=600,
                    type="pil"
                )
                
                status_display = gr.Markdown("_Ready to generate_", elem_classes="status-display")
                
                # How It Works - Full width section (same spacing as Generated Image section above)
                gr.Markdown("### 💡 How It Works")
                gr.Markdown("""
                Meridian transforms geographic coordinates and dates into historically accurate visual scenes through a unique three-step process:
                
                1. **Historical Event Discovery**: When you provide coordinates and a date, Meridian searches through curated historical databases and Wikidata to find events that occurred near that location and time. Using Haversine distance calculations (which account for Earth's curvature), the system identifies the most relevant historical events, prioritizing those that match your exact year.
                
                2. **Intelligent Prompt Generation**: Once a historical event is identified, Meridian creates a focused, detailed description that emphasizes the event name, location, and year—the three most critical elements for accurate image generation. The system considers time of day (affecting lighting), season, regional architecture, and key participants to build a vivid scene description.
                
                3. **Photorealistic Image Creation**: The generated prompt is sent to FLUX.1-dev, an advanced image generation model, which creates a historically accurate scene. Negative prompts automatically prevent anachronisms (like modern technology appearing in ancient scenes), ensuring period-appropriate results.
                
                All of this happens automatically—you simply enter coordinates and a date, or describe what you're looking for in natural language.
                """)
                
                # Technical Capabilities - Full width section (same spacing as Generated Image section)
                gr.Markdown("### ⚙️ Technical Capabilities")
                gr.Markdown("""
                **Solving the Geospatial Challenge**: Traditional image generation models struggle with coordinates because they tokenize numbers like "52.5163" as separate symbols rather than understanding them as geographic locations. Meridian bridges this gap by maintaining a structured geospatial-historical database that maps precise coordinates to historical events, then translating those events into rich semantic descriptions that image models understand.
                
                **Dual Data Sources**: Meridian combines a curated database of pivotal historical events with real-time Wikidata queries, providing both quality (hand-selected events with rich metadata) and breadth (comprehensive coverage of global history). Events are scored by geographic proximity, temporal accuracy, and source reliability.
                
                **Year-Weighted Matching**: The system prioritizes events that match your exact year over nearby events from different time periods. This ensures that when you request "Rome, 44 BCE," you get Julius Caesar's assassination, not a medieval event that happened at the same coordinates centuries later.
                
                **Period-Accurate Generation**: Negative prompts automatically exclude anachronistic elements based on the event's era. For example, ancient scenes won't include modern clothing or technology, while 19th-century scenes exclude digital devices. The system also adapts architectural styles, clothing, and technology to match the historical period.
                
                **Time-Aware Details**: Meridian considers the specific hour you provide (affecting lighting—dawn, midday, dusk, or night) and the month/latitude combination (determining season and atmospheric conditions) to create scenes that feel authentic to the moment in history.
                
                **MCP Integration**: Through Model Context Protocol, Meridian can be called programmatically by AI assistants like Claude, enabling automated historical visualization workflows for education, research, and content creation.
                """)
                
                with gr.Accordion("📜 Historical Timeline", open=False):
                    timeline_display = gr.Markdown("Nearby events will appear here after generation.")
        
        def on_prompt_override_change(text):
            interactive = not bool(text.strip())
            update = gr.update(interactive=interactive)
            return update, update, update, update, update, gr.update(interactive=interactive)

        prompt_override.change(
            fn=on_prompt_override_change,
            inputs=[prompt_override],
            outputs=[latitude, longitude, year, month, day, hour],
        )

        # Event handler
        def on_generate(prompt_override_text, lat, lon, yr, mon, dy, hr, mood_val, model_val, prompt_box_text):
            lat_val = float(lat) if lat is not None else 0.0
            lon_val = float(lon) if lon is not None else 0.0
            year_val = int(yr)
            month_val = int(mon)
            day_val = int(dy)
            hour_val = int(hr)
            custom_text = prompt_box_text
            derived_note = ""

            if prompt_override_text and prompt_override_text.strip():
                custom_text = prompt_override_text.strip()
                parsed: ParsedPrompt = parse_prompt_context(custom_text)
                if parsed.lat is not None and parsed.lon is not None and parsed.confidence >= 0.35:
                    lat_val = parsed.lat
                    lon_val = parsed.lon
                    if parsed.year is not None:
                        year_val = parsed.year
                    if parsed.month is not None:
                        month_val = parsed.month
                    if parsed.day is not None:
                        day_val = parsed.day
                    if parsed.hour is not None:
                        hour_val = parsed.hour % 24
                    derived_note = (
                        f"🧭 Parsed from prompt (confidence {parsed.confidence:.2f}) · "
                        f"{lat_val:.4f}, {lon_val:.4f}, year {year_val}"
                    )
            else:
                    derived_note = "⚠️ Could not confidently parse prompt context; using manual inputs."

            image, prompt, hint, status, timeline = process_coordinates(
                lat_val, lon_val, year_val, month_val, day_val, hour_val, mood_val, model_val, custom_text
            )

            if derived_note:
                hint = f"{hint}\n{derived_note}"
            if derived_note.startswith("⚠️"):
                status = f"{status}\n{derived_note}"
            elif derived_note.startswith("🧭"):
                status = f"{status}\nInterpreted prompt context successfully."
                timeline = timeline.replace(
                    "### Nearby Historical Events",
                    f"### Nearby Historical Events\n\n_Prompt-derived coordinates:_ {lat_val:.4f}, {lon_val:.4f}",
                    1,
                )

            return image, prompt, hint, status, timeline

        generate_btn.click(
            fn=on_generate,
            inputs=[prompt_override, latitude, longitude, year, month, day, hour, mood, model_choice, prompt_box],
            outputs=[image_output, prompt_box, hint_display, status_display, timeline_display]
        )
    
    return demo

# ==========================
# MCP Server Support
# ==========================

def mcp_generate_from_coordinates(
    latitude: float,
    longitude: float,
    year: int,
    month: int = 1,
    day: int = 1,
    hour: int = 12,
    mood: str = "Documentary",
    model: str = "FLUX.1-dev (High Quality)",
) -> Dict:
    """MCP tool: generates image from coordinates and date."""
    try:
        nearby_events = get_events_by_coordinates(
            latitude, longitude, year, radius_km=300, limit=5
        )
        image, prompt, hint, status, timeline = process_coordinates(
            latitude,
            longitude,
            year,
            month,
            day,
            hour,
            mood,
            model,
        )
        
        return {
            "success": True,
            "prompt": prompt,
            "hint": hint,
            "status": status,
            "image_generated": image is not None,
            "events": [format_event_digest(event) for event in nearby_events],
            "timeline_markdown": timeline,
        }
    except Exception as e:
        return {
            "success": False,
            "error": str(e)
        }


def mcp_get_events_by_coordinates(
    latitude: float,
    longitude: float,
    year: int,
    radius_km: float = 250.0,
    limit: int = 5,
) -> Dict:
    """MCP tool: finds nearby historical events."""
    try:
        payload = get_events_response(latitude, longitude, year, radius_km=radius_km, limit=limit)
        payload["success"] = True
        return payload
    except Exception as exc:
        return {"success": False, "error": str(exc)}


def mcp_get_event_context(identifier: str) -> Dict:
    """MCP tool: gets detailed info about an event by name or slug."""
    event = get_event_by_slug(identifier)
    if not event:
        event = get_event_by_name(identifier)
    if not event:
        return {"success": False, "error": f"Event '{identifier}' not found"}

    context = build_event_context(event)
    context["artifacts"] = get_artifacts_for_year(event.get("year", 0))
    context["source"] = event.get("source", "curated")
    return {"success": True, "context": context}


def mcp_search_wikidata_events(
    latitude: float,
    longitude: float,
    year: int,
    radius_km: float = 300.0,
    limit: int = 10,
) -> Dict:
    """MCP tool: searches Wikidata for events at coordinates and year."""
    if not WIKIDATA_MCP_AVAILABLE:
        return {
            "success": False,
            "error": "Wikidata service not available",
        }
    
    return mcp_search_historical_events(
        latitude=latitude,
        longitude=longitude,
        year=year,
        radius_km=radius_km,
        limit=limit,
    )


def mcp_get_wikidata_event(qid: str) -> Dict:
    """MCP tool: gets Wikidata event details by QID."""
    if not WIKIDATA_MCP_AVAILABLE:
        return {
            "success": False,
            "error": "Wikidata service not available",
        }
    
    return mcp_get_event_by_qid(qid)


def mcp_search_events_globally(
    latitude: float,
    longitude: float,
    year: int,
    radius_km: float = 500.0,
    limit: int = 10,
) -> Dict:
    """MCP tool: searches for events with wider radius, combining curated and Wikidata data."""
    try:
        events = search_events_globally(
            lat=latitude,
            lon=longitude,
            year=year,
            radius_km=radius_km,
            limit=limit,
        )
        return {
            "success": True,
            "query": {
                "latitude": latitude,
                "longitude": longitude,
                "year": year,
                "radius_km": radius_km,
            },
            "count": len(events),
            "events": [format_event_digest(e) for e in events],
            "sources": list(set(e.get("source", "curated") for e in events)),
        }
    except Exception as e:
        return {
            "success": False,
            "error": str(e),
        }

# ==========================
# Launch
# ==========================

def find_available_port(start_port=7860, max_attempts=10):
    """Find an available port starting from start_port"""
    import socket
    for i in range(max_attempts):
        port = start_port + i
        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        try:
            sock.bind(('0.0.0.0', port))
            sock.close()
            return port
        except OSError:
            sock.close()
            continue
    return None  # Fall back to Gradio's auto port selection

if __name__ == "__main__":
    app = create_app()
    # Hugging Face Spaces handles port automatically
    # Disable SSR to avoid Node.js server issues
    port = os.getenv("GRADIO_SERVER_PORT")
    if port:
        try:
            port = int(port)
            app.launch(server_name="0.0.0.0", server_port=port, share=False, ssr_mode=False)
        except ValueError:
            app.launch(server_name="0.0.0.0", share=False, ssr_mode=False)
    else:
        # Hugging Face Spaces - let Gradio handle everything automatically
        app.launch(ssr_mode=False)