import gradio as gr
import pandas as pd
import random

# Default list of participants
participants_list = [
    ["Darsh", "😍"], ["Jazmine", "🥂"], ["Gnanam", "🥂"], ["DT", "🥂"],
    ["Rajen", "😍"], ["Thiru", "😍"], ["Shageenderan", "😍"], ["Nirthanjali", "😍"],
    ["Shyahana", "😍"], ["Rischendera", "😍"], ["Sothie", "🤩"], ["Niranjan", "🤩"],
    ["Sonali", "🤩"], ["Rehana", "🤩"], ["Tanisha", "🤩"], ["Rohan", "🤩"],
    ["Secret male", "🥂"], ["Pansy", "🥂"], ["Chandran", "😜"], ["Vasanthi", "😜"],
    ["Ashok", "🙏🏽"], ["Jane", "🙏🏽"]
]

# Function to add a participant
def add_participant(name, emoji):
    if not name or not emoji:
        return participants_list, "Please provide both a name and select an emoji."
    
    participants_list.append([name.strip(), emoji])
    return participants_list, f"{name} added successfully!"

# Function to remove a participant
def remove_participant(name):
    global participants_list
    participants_list = [p for p in participants_list if p[0] != name]
    return participants_list, f"{name} removed successfully!"

# Function to generate pairings ensuring emoji constraints
def generate_pairings():
    if len(participants_list) < 2:
        return "Please add at least two participants.", None

    # Extract names and emojis
    names = [name for name, emoji in participants_list]
    emojis = {name: emoji for name, emoji in participants_list}

    # Shuffle names for randomization
    receivers = names[:]
    random.shuffle(receivers)

    # Retry until all constraints are satisfied
    max_attempts = 1000
    attempts = 0
    while any(
        giver == receiver or emojis[giver] == emojis[receiver]
        for giver, receiver in zip(names, receivers)
    ):
        random.shuffle(receivers)
        attempts += 1
        if attempts > max_attempts:
            return "Failed to generate valid pairings. Please adjust the participant list.", None

    # Create pairings
    pairings = [{"Giver": giver, "Receiver": receiver} for giver, receiver in zip(names, receivers)]
    
    # Return pairings as a DataFrame for display and download
    pairings_df = pd.DataFrame(pairings)
    return None, pairings_df

# Function to download pairings as CSV
def download_pairings(pairings_df):
    if pairings_df is None or len(pairings_df) == 0:
        return None
    
    # Save the DataFrame to a CSV file and return the file path
    csv_path = "pairings.csv"
    pairings_df.to_csv(csv_path, index=False)
    return csv_path

# Gradio Interface
with gr.Blocks() as interface:
    gr.Markdown("## 🎅 Secret Santa Pairing Generator 🎄")
    gr.Markdown(
        "Add participants by entering their name and selecting their emoji group. "
        "Generate pairings and download the results as a CSV. \nCreated by Shageenderan Sapai"
    )
    
    # Section for adding participants
    with gr.Row():
        name_input = gr.Textbox(label="Participant Name", placeholder="Enter name")
        emoji_dropdown = gr.Dropdown(
            label="Select Emoji Group",
            choices=["😍", "🥂", "🤩", "😜", "🙏🏽"],
            value="😍",
        )
        add_button = gr.Button("Add Participant")
    
    # Section for displaying participants
    participant_table = gr.Dataframe(
        headers=["Name", "Emoji"],
        datatype=["str", "str"],
        value=participants_list,
        label="Current Participants"
    )
    
    # Section for removing participants
    remove_name_input = gr.Textbox(label="Name to Remove", placeholder="Enter name to remove")
    remove_button = gr.Button("Remove Participant")
    
    # Section for generating pairings
    generate_button = gr.Button("Generate Pairings", variant="primary")
    pairing_output = gr.Dataframe(
        headers=["Giver", "Receiver"],
        datatype=["str", "str"],
        label="Generated Pairings"
    )
    download_pairings_button = gr.Button("Download Pairings as CSV")
    download_file = gr.File(label="CSV File")

    # Interactivity
    add_button.click(
        add_participant,
        inputs=[name_input, emoji_dropdown],
        outputs=[participant_table, gr.Text(label="Message")]
    )
    remove_button.click(
        remove_participant,
        inputs=[remove_name_input],
        outputs=[participant_table, gr.Text(label="Message")]
    )
    generate_button.click(
        generate_pairings,
        inputs=[],
        outputs=[gr.Text(label="Error Message"), pairing_output]
    )
    download_pairings_button.click(
        download_pairings,
        inputs=[pairing_output],
        outputs=[download_file]
    )

# Launch the interface
interface.launch()