import streamlit as st
from pathlib import Path
from datetime import datetime

# Application title
st.set_page_config(page_title="To-Do List \n Notebook", page_icon="📝", layout="centered")

# Create an uploads folder if it doesn't exist
Path("uploads").mkdir(exist_ok=True)

# App header
st.title("📝  To-Do List \n Notebook")
st.subheader("Your tasks, your way!")

# App description
st.write("Organize your tasks with notes, images, and audio. Edit, save, or delete tasks seamlessly!")

# Initialize task list in the session state
if "tasks" not in st.session_state:
    st.session_state.tasks = []

# Initialize task input fields in the session state
if "title" not in st.session_state:
    st.session_state.title = ""
if "description" not in st.session_state:
    st.session_state.description = ""
if "bg_color" not in st.session_state:
    st.session_state.bg_color = "#ffffff"
if "image_files" not in st.session_state:
    st.session_state.image_files = []
if "audio_file" not in st.session_state:
    st.session_state.audio_file = None
if "editing_index" not in st.session_state:
    st.session_state.editing_index = None  # To track which task is being edited

# Helper function to save uploaded files
def save_uploaded_file(uploaded_file):
    try:
        file_path = Path("uploads") / uploaded_file.name
        with open(file_path, "wb") as f:
            f.write(uploaded_file.getbuffer())
        return str(file_path)
    except Exception as e:
        st.error(f"Error saving file: {e}")
        return None

# Function to add a new task with exception handling
def add_task(title, description, image_files, audio_file, bg_color):
    try:
        if not title.strip():
            raise ValueError("Title cannot be empty.")
        if not description.strip():
            raise ValueError("Description cannot be empty.")
        
        new_task = {
            "title": title,
            "description": description,
            "images": [save_uploaded_file(image) for image in image_files] if image_files else [],
            "audio": save_uploaded_file(audio_file) if audio_file else None,
            "bg_color": bg_color,
        }
        st.session_state.tasks.append(new_task)
        st.success(f"Task '{title}' added successfully!")

        # Clear the inputs after adding the task
        clear_fields()  # Call the function to clear fields
    except ValueError as ve:
        st.error(f"Error: {ve}")
    except Exception as e:
        st.error(f"Error adding task: {e}")

# Function to delete a task
def delete_task(index):
    try:
        st.session_state.tasks.pop(index)
        st.success("Task deleted successfully!")
        st.session_state.editing_index = None  # Reset editing index after deletion
    except Exception as e:
        st.error(f"Error deleting task: {e}")

# Function to edit a task
def edit_task(index, new_title, new_description, new_images, new_audio, new_bg_color):
    try:
        task = st.session_state.tasks[index]
        task["title"] = new_title
        task["description"] = new_description
        task["images"] = [save_uploaded_file(img) for img in new_images] if new_images else task["images"]
        task["audio"] = save_uploaded_file(new_audio) if new_audio else task["audio"]
        task["bg_color"] = new_bg_color
        st.success(f"Task '{new_title}' updated successfully!")
        st.session_state.editing_index = None  # Reset editing index after task is edited
    except Exception as e:
        st.error(f"Error editing task: {e}")

# Function to clear the fields after a task is added or edited
def clear_fields():
    st.session_state.title = ""
    st.session_state.description = ""
    st.session_state.bg_color = "#ffffff"
    st.session_state.image_files = []
    st.session_state.audio_file = None
    st.session_state.editing_index = None  # Reset editing index

# Add task section
with st.expander("➕ Add a New Task"):
    if st.session_state.editing_index is not None:
        # If editing, populate fields with the existing task data
        task_to_edit = st.session_state.tasks[st.session_state.editing_index]
        st.session_state.title = st.text_input("Title", value=task_to_edit["title"])
        st.session_state.description = st.text_area("Description", value=task_to_edit["description"])
        
        # Multiple images upload (without assigning directly to session state)
        image_files = st.file_uploader("Upload Images (optional)", type=["png", "jpg", "jpeg"], accept_multiple_files=True)
        if image_files:
            st.session_state.image_files = image_files
        
        audio_file = st.file_uploader("Upload Audio (optional)", type=["mp3", "wav"], accept_multiple_files=False)
        if audio_file:
            st.session_state.audio_file = audio_file
        
        st.session_state.bg_color = st.color_picker("Pick Background Color", value=task_to_edit["bg_color"])

        if st.button("Save Changes"):
            edit_task(st.session_state.editing_index, st.session_state.title, st.session_state.description, st.session_state.image_files, st.session_state.audio_file, st.session_state.bg_color)
        st.button("Cancel Edit", on_click=clear_fields)
    else:
        # If not editing, show empty input fields
        st.session_state.title = st.text_input("Title", placeholder="Enter task title...", value=st.session_state.title)
        st.session_state.description = st.text_area("Description", placeholder="Write your task details here...", value=st.session_state.description)
        
        # Multiple images upload (without assigning directly to session state)
        image_files = st.file_uploader("Upload Images (optional)", type=["png", "jpg", "jpeg"], accept_multiple_files=True)
        if image_files:
            st.session_state.image_files = image_files
        
        audio_file = st.file_uploader("Upload Audio (optional)", type=["mp3", "wav"], accept_multiple_files=False)
        if audio_file:
            st.session_state.audio_file = audio_file
        
        st.session_state.bg_color = st.color_picker("Pick Background Color", value=st.session_state.bg_color)

        if st.button("Add Task"):
            add_task(st.session_state.title, st.session_state.description, st.session_state.image_files, st.session_state.audio_file, st.session_state.bg_color)

    # Add "Clear" button to reset all input fields
    if st.button("Clear"):
        clear_fields()

# Show tasks
if st.session_state.tasks:
    st.subheader("📋 Your Tasks")
    for i, task in enumerate(st.session_state.tasks):
        with st.container():
            # Apply background color
            st.markdown(
                f"<div style='background-color: {task['bg_color']}; padding: 10px; border-radius: 8px;'>",
                unsafe_allow_html=True,
            )

            # Task content
            col1, col2 = st.columns([6, 1])
            with col1:
                st.write(f"### TASK # {i + 1}")
                st.write(f"**Title:** {task['title']}")
                st.write(f"**Description:** {task['description']}")

                # Display images if available
                if task["images"]:
                    for img in task["images"]:
                        st.image(img, caption="Attached Image", use_column_width=True)

                # Display audio player if available
                if task["audio"]:
                    st.audio(task["audio"], format="audio/mp3")

            with col2:
                # Edit button
                if st.button("✏️ Edit", key=f"edit_{i}"):
                    st.session_state.editing_index = i  # Set the task index to be edited
                # Delete button
                if st.button("🗑️ Delete", key=f"delete_{i}"):
                    delete_task(i)

            # Close background div
            st.markdown("</div>", unsafe_allow_html=True)

else:
    st.info("You have no tasks. Add a new task to get started!")

# Footer
st.write("---")
st.write("✨ Made with ❤️ using Streamlit")