import streamlit as st
import time
import base64
from io import BytesIO
from PIL import Image
from config import Config
from api.novita_client import NovitaClient, NovitaAPIError
from utils.validators import (
    validate_api_key, validate_prompt, validate_image,
    validate_model_parameters, validate_seed
)

# Set page configuration
st.set_page_config(
    page_title=Config.APP_TITLE,
    page_icon=Config.APP_ICON,
    layout="centered"
)

# Validate configuration
config_validation = Config.validate_config()
if not config_validation["valid"]:
    st.error("Configuration error: " + ", ".join(config_validation["errors"]))
if config_validation["warnings"]:
    for warning in config_validation["warnings"]:
        st.warning(warning)

def image_to_base64(image):
    """Convert PIL image to base64 string"""
    buffer = BytesIO()
    image.save(buffer, format="PNG")
    img_str = base64.b64encode(buffer.getvalue()).decode()
    return f"data:image/png;base64,{img_str}"

def generate_video(api_key, prompt, model_type="seedance-v1-lite-t2v", resolution="720p",
                  duration=5, aspect_ratio="16:9", image_base64=None, fix_camera=False, seed=None):
    """Generate video function"""
    try:
        client = NovitaClient(api_key)
        return client.generate_video(
            prompt=prompt,
            model_type=model_type,
            resolution=resolution,
            duration=duration,
            aspect_ratio=aspect_ratio,
            image_base64=image_base64,
            fix_camera=fix_camera,
            seed=seed
        )
    except NovitaAPIError as e:
        st.error(f"API Error: {str(e)}")
        if e.status_code == 401:
            st.error("🔑 Please check if API key is correct")
        elif e.status_code == 429:
            st.warning("⏱️ Too many requests, please try again later")
        elif e.status_code == 402:
            st.error("💳 Insufficient account balance, please recharge")
        return None
    except Exception as e:
        st.error(f"Unknown error: {str(e)}")
        return None

def check_task_status(api_key, task_id):
    """Check task status"""
    try:
        client = NovitaClient(api_key)
        return client.check_task_status(task_id)
    except Exception as e:
        return "error", str(e)

def save_video_to_history(video_url, prompt, model_type, resolution, duration, aspect_ratio):
    """Save video information to history, keeping only latest 5"""
    import datetime

    video_info = {
        "url": video_url,
        "prompt": prompt[:100] + "..." if len(prompt) > 100 else prompt,  # Truncate long prompts
        "model": model_type,
        "resolution": resolution,
        "duration": duration,
        "aspect_ratio": aspect_ratio,
        "timestamp": datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S")
    }

    # Add to beginning of list
    st.session_state.video_history.insert(0, video_info)

    # Keep only latest 5
    if len(st.session_state.video_history) > 5:
        st.session_state.video_history = st.session_state.video_history[:5]

def main():
    st.title(Config.APP_TITLE)
    st.markdown("Generate high-quality videos from text descriptions or animate your images using AI")


    # Initialize session state for model synchronization
    if 'selected_model_key' not in st.session_state:
        st.session_state.selected_model_key = list(Config.MODEL_OPTIONS.keys())[0]

    # Initialize session state for video history
    if 'video_history' not in st.session_state:
        st.session_state.video_history = []

    # Minimal sidebar
    with st.sidebar:
        st.header("⚙️ Settings")

        # Simple privacy notice
        st.info("🔒 Your API key is session-only and never stored")

        # API Key
        default_key = Config.NOVITA_API_KEY if Config.NOVITA_API_KEY else ""
        api_key = st.text_input(
            "🔑 API Key",
            value=default_key,
            type="password",
            help="Get your API key from novita.ai"
        )

        if api_key and not validate_api_key(api_key):
            st.error("Invalid API key format")
    
    # Main content area
    tab1, tab2, tab3 = st.tabs(["Text to Video", "Image to Video", "Video History"])

    with tab1:
        st.subheader("📝 Text to Video")

        # Model selection
        st.markdown("### 🎯 Model")
        t2v_model = st.selectbox(
            "Model Type",
            ["Lite", "Pro"],
            key="t2v_model"
        )

        model_type_t2v = f"seedance-v1-{t2v_model.lower()}-t2v"

        # Video settings
        st.markdown("### 📹 Settings")
        col1, col2, col3 = st.columns(3)

        with col1:
            resolution = st.selectbox("Resolution", Config.RESOLUTIONS, index=1)

        with col2:
            duration = st.selectbox("Duration", Config.DURATIONS, format_func=lambda x: f"{x}s")

        with col3:
            aspect_ratio = st.selectbox("Aspect", Config.ASPECT_RATIOS)

        # Advanced options
        with st.expander("🔧 Advanced", expanded=False):
            col1, col2 = st.columns(2)
            with col1:
                fix_camera = st.checkbox("📹 Fix Camera", value=False)

            with col2:
                use_seed = st.checkbox("🎲 Use Seed")
                seed = None
                if use_seed:
                    seed = st.number_input("Seed", min_value=0, max_value=2147483647, value=42)

        # Prompt
        st.markdown("### ✍️ Description")
        prompt = st.text_area(
            "Describe your video",
            placeholder="Cinematic. Wide shot. A kitten playing in a garden. Golden hour lighting.",
            height=100,
            max_chars=2000
        )

        # Generate button
        if st.button("🚀 Generate Video", type="primary", key="text_generate"):
            if not api_key:
                st.error("Enter API key in sidebar")
                return
            if not prompt:
                st.error("Enter video description")
                return

            generate_and_display_video(api_key, prompt, model_type_t2v, resolution,
                                     duration, aspect_ratio, None, fix_camera, seed)
    
    with tab2:
        st.subheader("🖼️ Image to Video")

        # Model selection
        st.markdown("### 🎯 Model")
        i2v_model = st.selectbox(
            "Model Type",
            ["Lite", "Pro"],
            key="i2v_model"
        )

        model_type_i2v = f"seedance-v1-{i2v_model.lower()}-i2v"

        # Video settings
        st.markdown("### 📹 Settings")
        col1, col2, col3 = st.columns(3)

        with col1:
            resolution = st.selectbox("Resolution", Config.RESOLUTIONS, index=1, key="i2v_resolution")

        with col2:
            duration = st.selectbox("Duration", Config.DURATIONS, format_func=lambda x: f"{x}s", key="i2v_duration")

        with col3:
            aspect_ratio = st.selectbox("Aspect", Config.ASPECT_RATIOS, key="i2v_aspect")

        # Advanced options
        with st.expander("🔧 Advanced", expanded=False):
            col1, col2 = st.columns(2)
            with col1:
                fix_camera = st.checkbox("📹 Fix Camera", value=False, key="i2v_fix_camera")

            with col2:
                use_seed = st.checkbox("🎲 Use Seed", key="i2v_use_seed")
                seed = None
                if use_seed:
                    seed = st.number_input("Seed", min_value=0, max_value=2147483647, value=42, key="i2v_seed")

        # Upload section
        st.markdown("### 📤 Image")
        uploaded_file = st.file_uploader("Upload image", type=Config.SUPPORTED_IMAGE_FORMATS)

        image_base64 = None
        if uploaded_file is not None:
            is_valid, error_msg, processed_image = validate_image(uploaded_file)
            if not is_valid:
                st.error(error_msg)
            else:
                st.image(processed_image, use_column_width=True)
                image_base64 = image_to_base64(processed_image)

        # Prompt section
        st.markdown("### 🎬 Description")
        prompt_i2v = st.text_area(
            "Describe what you want to happen",
            placeholder="Camera zooms in. Person walks forward. Leaves blow in wind.",
            height=100,
            max_chars=2000
        )

        # Generate button
        if st.button("🚀 Generate Video", type="primary", key="image_generate"):
            if not api_key:
                st.error("Enter API key in sidebar")
                return
            if not uploaded_file:
                st.error("Upload an image first")
                return
            if not prompt_i2v:
                st.error("Describe what you want to happen")
                return

            generate_and_display_video(api_key, prompt_i2v, model_type_i2v, resolution,
                                     duration, aspect_ratio, image_base64, fix_camera, seed)

    with tab3:
        st.subheader("📚 History")

        if not st.session_state.video_history:
            st.info("No videos yet")
        else:
            if st.button("Clear", type="secondary"):
                st.session_state.video_history = []
                st.rerun()

            # Display video history in simple cards
            for i, video in enumerate(st.session_state.video_history):
                st.markdown("---")
                col1, col2 = st.columns([3, 1])

                with col1:
                    st.video(video['url'])

                with col2:
                    # Create download button with direct download
                    video_url = video['url']
                    st.markdown(f"""
                    <a href="{video_url}" download="video_{i+1}.mp4" style="
                        display: inline-block;
                        padding: 0.5rem 1rem;
                        background-color: #0066cc;
                        color: white;
                        text-decoration: none;
                        border-radius: 4px;
                        font-weight: 500;
                        text-align: center;
                        width: 100%;
                        box-sizing: border-box;
                    ">📥 Download</a>
                    """, unsafe_allow_html=True)

                    st.text(f"{video['model']}")
                    st.text(f"{video['timestamp']}")
                    st.text(f"'{video['prompt'][:30]}...'")  # Short prompt preview

def generate_and_display_video(api_key, prompt, model_type, resolution, duration, 
                             aspect_ratio, image_base64, fix_camera, seed):
    """Universal function to generate and display video"""
    # Generate video
    with st.spinner("Submitting task..."):
        task_id = generate_video(api_key, prompt, model_type, resolution, 
                               duration, aspect_ratio, image_base64, fix_camera, seed)
    
    if task_id:
        st.success(f"✅ Task submitted! Task ID: {task_id}")
        
        # Display parameter information
        with st.expander("📋 Generation Parameters"):
            st.write(f"**Model**: {model_type}")
            st.write(f"**Resolution**: {resolution}")
            st.write(f"**Duration**: {duration} seconds")
            st.write(f"**Aspect Ratio**: {aspect_ratio}")
            if fix_camera:
                st.write("**Camera**: Fixed")
            if seed is not None:
                st.write(f"**Seed**: {seed}")
        
        # Wait for results
        progress_bar = st.progress(0)
        status_placeholder = st.empty()

        # Dynamically calculate timeout
        max_wait_time = Config.calculate_timeout(model_type, resolution, duration)
        check_interval = Config.STATUS_CHECK_INTERVAL

        # Display estimated wait time
        estimated_min = max_wait_time // 60
        estimated_sec = max_wait_time % 60
        st.info(f"⏱️ Maximum wait time: {estimated_min}min {estimated_sec}sec (typically completes in 2-5 minutes)")
        st.info("💡 Keep this page open - it will automatically update when your video is ready!")

        for i in range(0, max_wait_time, check_interval):
            status, result = check_task_status(api_key, task_id)
            
            if status == "completed":
                progress_bar.progress(100)
                if result:
                    status_placeholder.success("🎉 Video generation completed!")
                    st.video(result)
                    st.markdown(f"[📥 Download Video]({result})")

                    # Save video to history
                    save_video_to_history(result, prompt, model_type, resolution, duration, aspect_ratio)
                    st.success("✅ Video saved to history!")
                else:
                    status_placeholder.error("❌ Video generation completed but video file not found")
                break
            elif status == "failed":
                status_placeholder.error(f"❌ Generation failed: {result}")
                break
            elif status == "error":
                status_placeholder.error(f"❌ Error checking status: {result}")
                break
            else:
                progress = min((i / max_wait_time) * 90, 90)  # Show maximum 90%
                progress_bar.progress(int(progress))

                # More user-friendly status messages
                elapsed_min = i // 60
                elapsed_sec = i % 60
                if status == "processing":
                    status_msg = f"🎨 Creating your video... ({elapsed_min:02d}:{elapsed_sec:02d})"
                elif status in ["pending", "queued"]:
                    status_msg = f"⏳ Your video is in queue... ({elapsed_min:02d}:{elapsed_sec:02d})"
                else:
                    status_msg = f"🔄 Generating video... ({status}) - {elapsed_min:02d}:{elapsed_sec:02d}"

                status_placeholder.info(status_msg)
                time.sleep(check_interval)
        else:
            status_placeholder.warning(f"⏰ After waiting {max_wait_time // 60} minutes, still not completed. Video may still be generating. Task ID: {task_id}")
            st.info("💡 Tip: You can save the Task ID and check results later using the same API key")

    # Comprehensive footer help section
    st.markdown("---")
    col1, col2, col3 = st.columns(3)

    with col1:
        with st.expander("📚 Complete Guide", expanded=False):
            st.markdown("""
            **Getting Started:**
            1. Get API key from [Novita AI](https://novita.ai)
            2. Choose your generation mode (Text-to-Video or Image-to-Video)
            3. Configure model and video settings
            4. Follow the prompt/motion tips for best results

            **Model Types:**
            - 🎨 **Pro**: Best quality, takes longer (4-8 minutes)
            - ⚡ **Lite**: Good quality, faster results (2-3 minutes)

            **Need Help?**
            Check the expandable tip sections in each tab for detailed guidance.
            """)

    with col2:
        with st.expander("⚡ Quick Tips", expanded=False):
            st.markdown("""
            **For Better Results:**
            - Be specific in descriptions
            - Include lighting and camera angles
            - Use descriptive words: "cinematic", "golden hour", "close-up"
            - Start simple, then add more details

            **Common Issues:**
            - No API key → Get one from novita.ai
            - Generation fails → Check account credits
            - Slow results → Try Lite model first
            - Poor quality → Use Pro model with detailed prompts
            """)

    with col3:
        with st.expander("🔧 Technical & Privacy Info", expanded=False):
            st.markdown("""
            **Generation Times:**
            - Lite models: 2-3 minutes typically
            - Pro models: 4-8 minutes typically
            - Higher resolution: +30-50% time
            - Longer duration: +50-100% time

            **File Limits:**
            - Images: Max 10MB
            - Formats: PNG, JPG, JPEG
            - Video output: MP4 format

            **🔒 Privacy & Security:**
            - **API keys NEVER saved or stored**
            - **Session-only usage** - cleared when you leave
            - Images processed securely via HTTPS
            - Videos auto-deleted after download
            - No personal data collected or retained
            - You control your API key at all times
            """)

    st.markdown("---")

# Footer information
st.markdown("""
<div style='text-align: center; color: #666; margin-top: 2rem;'>
    <p>Powered by <a href='https://novita.ai' target='_blank'>Novita AI</a> |
    <a href='https://novita.ai/docs/api-reference/model-apis-seedance-v1-lite-t2v' target='_blank'>Seedance V1 Documentation</a></p>
</div>
""", unsafe_allow_html=True)

if __name__ == "__main__":
    main()