use crate::{consts::Colors, Context};

use color_eyre::eyre::{eyre, Result};
use poise::serenity_prelude::{self as serenity, CreateEmbedAuthor, CreateEmbedFooter};
use poise::CreateReply;
use rand::seq::SliceRandom;
use serenity::{CreateEmbed, Message};
use url::Url;

/*
 * chooses a random element from an array
 */
pub fn random_choice<const N: usize>(arr: [&str; N]) -> Result<String> {
	let mut rng = rand::thread_rng();
	let resp = arr
		.choose(&mut rng)
		.ok_or_else(|| eyre!("Couldn't choose random object from array:\n{arr:#?}!"))?;

	Ok((*resp).to_string())
}

// waiting for `round_char_boundary` to stabilize
#[allow(clippy::cast_possible_wrap)]
pub fn floor_char_boundary(s: &str, index: usize) -> usize {
	if index >= s.len() {
		s.len()
	} else {
		let lower_bound = index.saturating_sub(3);
		let new_index = s.as_bytes()[lower_bound..=index]
			.iter()
			.rposition(|&b| (b as i8) >= -0x40); // b.is_utf8_char_boundary

		// Can be made unsafe but whatever
		lower_bound + new_index.unwrap()
	}
}

pub async fn send_url_as_embed(ctx: Context<'_>, url: String) -> Result<()> {
	let parsed = Url::parse(&url)?;

	let title = parsed
		.path_segments()
		.unwrap()
		.last()
		.unwrap_or("image")
		.replace("%20", " ");

	let embed = CreateEmbed::new()
		.title(title)
		.image(&url)
		.url(url)
		.color(Colors::Blue);
	let reply = CreateReply::default().embed(embed);

	ctx.send(reply).await?;

	Ok(())
}

pub async fn resolve_message_to_embed(ctx: &serenity::Context, msg: &Message) -> CreateEmbed {
	let truncation_point = floor_char_boundary(&msg.content, 700);
	let truncated_content = if msg.content.len() <= truncation_point {
		msg.content.to_string()
	} else {
		format!("{}...", &msg.content[..truncation_point])
	};

	let color = msg
		.member(ctx)
		.await
		.ok()
		.and_then(|m| m.highest_role_info(&ctx.cache))
		.and_then(|(role, _)| role.to_role_cached(&ctx.cache))
		.map(|role| role.colour);

	let attached_image = msg
		.attachments
		.iter()
		.filter(|a| {
			a.content_type
				.as_ref()
				.filter(|ct| ct.contains("image/"))
				.is_some()
		})
		.map(|a| &a.url)
		.next();

	let attachments_len = msg.attachments.len();

	let mut embed = msg
		.embeds
		.first()
		.map(|embed| CreateEmbed::from(embed.clone()))
		.unwrap_or_default();

	let author = CreateEmbedAuthor::new(&msg.author.name).icon_url(msg.author.face());
	embed = embed.author(author);

	if let Some(color) = color {
		embed = embed.color(color);
	}

	if let Some(attachment) = attached_image {
		embed = embed.image(attachment);
	}

	if attachments_len > 1 {
		embed = embed.footer(CreateEmbedFooter::new(format!(
			"{attachments_len} attachments"
		)));
	}

	embed = embed.description(truncated_content);
	embed
}