use crate::error::ManifoldResult;
use crate::ManifoldContext;
use poise::{ReplyHandle, serenity_prelude};
use poise::serenity_prelude::CreateEmbed;

pub async fn paginate(ctx: ManifoldContext<'_>, message: ReplyHandle<'_>, pages: Vec<CreateEmbed>, mut current_page: usize) -> ManifoldResult<()> {
    // Define some unique identifiers for the navigation buttons
    let ctx_id = ctx.id();
    let prev_button_id = format!("{}prev", ctx.id());
    let next_button_id = format!("{}next", ctx.id());

    // Send the embed with the first page as content
    message.edit(ctx, |m| {
        m.embeds = vec![pages[current_page].to_owned()];
        m.components(|b| {
            b.create_action_row(|b| {
                b.create_button(|b| b.custom_id(&prev_button_id).emoji('◀'))
                    .create_button(|b| b.custom_id(&next_button_id).emoji('▶'))
            })
        })
    }).await?;

    // Loop through incoming interactions with the navigation buttons
    while let Some(press) = serenity_prelude::CollectComponentInteraction::new(ctx)
        // We defined our button IDs to start with `ctx_id`. If they don't, some other command's
        // button was pressed
        .filter(move |press| press.data.custom_id.starts_with(&ctx_id.to_string()))
        // Timeout when no navigation button has been pressed for 24 hours
        .timeout(std::time::Duration::from_secs(300))
        .await
    {
        // Depending on which button was pressed, go to next or previous page
        if press.data.custom_id == next_button_id {
            current_page += 1;
            if current_page >= pages.len() {
                current_page = 0;
            }
        } else if press.data.custom_id == prev_button_id {
            current_page = current_page.checked_sub(1).unwrap_or(pages.len() - 1);
        } else {
            // This is an unrelated button interaction
            continue;
        }

        // Update the message with the new page contents
        press
            .create_interaction_response(ctx, |b| {
                b.kind(serenity_prelude::InteractionResponseType::UpdateMessage)
                    .interaction_response_data(|b| b.set_embeds(vec![pages[current_page.clone()].to_owned()]))
            })
            .await?;
    }

    Ok(())
}