use crate::utils::*;
use serde_json::Map;

use crate::serenity;
use crate::Error;
use crate::{Context, PrefixContext};
use poise::command;

use slug::slugify;
use std::fs;
use std::fs::File;
use std::io::Write;
use std::path::Path;

#[command(prefix_command, slash_command, description_localized("en-US", "View the latest handwriting challenge info."))]
pub async fn challenge(ctx: Context<'_>) -> Result<(), Error> {
    ctx.say(
        format!(
            "Tegaki Tuesday #{n}: <https://tegakituesday.com/{n}>",
            n = get_challenge_number()
        ),
    )
    .await?;
    Ok(())
}

#[command(prefix_command, broadcast_typing, description_localized("en-US", "Submit to the latest handwriting challenge."))]
pub async fn submit(ctx: PrefixContext<'_>) -> Result<(), Error> {
    // TODO: The code for this command needs to be refactored,
    // there are large duplicated sections that need to be merged somehow.
    let guild_data = get_guild_data();
    let guild = ctx.msg.guild_id.unwrap().as_u64().to_string();
    if !guild_data.contains_key(&guild)
        || !&guild_data[&guild]
            .as_object()
            .unwrap()
            .contains_key("submissionChannel")
    {
        ctx.msg.reply(&ctx.discord.http, "Submissions aren't enabled for this server yet.").await?;
        return Ok(());
    }
    let current_guild_data = &guild_data[&guild].as_object().unwrap();
    let submission_channel = current_guild_data["submissionChannel"].as_str().unwrap();
    if submission_channel != ctx.msg.channel_id.as_u64().to_string() {
        ctx.msg.reply(
            &ctx.discord.http,
            format!(
                "Sorry, submissions aren't permitted here. Please go to <#{}>. Thanks!",
                guild
            ),
        )
        .await?;
        return Ok(());
    }
    if ctx.msg.attachments.len() == 0 {
        ctx.msg.reply(&ctx.discord.http, "Please attach at least one image.").await?;
        return Ok(());
    }
    let challenge_number = get_challenge_number();
    let submission_images_dir = get_submission_images_dir();

    // Ensure that submission_images_dir exists
    let path = Path::new(&submission_images_dir);
    std::fs::create_dir_all(path)?;

    let mut submission_data = get_current_submission_data();
    let mut existing_submitter = false;
    let mut invalid_types = false;
    let mut requires_rebuild = false;
    for (i, submission) in submission_data.iter_mut().enumerate() {
        if is_matching_submission(&submission, &ctx.msg.author) {
            existing_submitter = true;
            let mut images = submission["images"].as_array_mut().unwrap().clone();
            for attachment in ctx.msg.attachments.iter() {
                let extension;
                if let Some(content_type) = &attachment.content_type {
                    if content_type == "image/png" {
                        extension = "png";
                    } else if content_type == "image/jpeg" {
                        extension = "jpg";
                    } else {
                        invalid_types = true;
                        continue;
                    }
                } else {
                    invalid_types = true;
                    continue;
                }
                requires_rebuild = true;
                let file_name = format!(
                    "{}-{}-{}-{}.{}",
                    i + 1,
                    slugify(&ctx.msg.author.name),
                    ctx.msg.author.discriminator,
                    images.len() + 1,
                    extension
                );
                images.push(file_name.clone().into());
                let image = reqwest::get(&attachment.url).await?.bytes().await?;
                let mut image_file =
                    File::create(format!("{}/{}", submission_images_dir, file_name))?;
                image_file.write_all(&image)?;
                image_file.flush()?;
            }
            submission["images"] = images.into();
            break;
        }
    }
    if !existing_submitter {
        let mut submitter_data = Map::new();
        submitter_data.insert(
            String::from("username"),
            format!("{}#{}", ctx.msg.author.name, ctx.msg.author.discriminator).into(),
        );
        let mut images: Vec<String> = Vec::new();
        for attachment in ctx.msg.attachments.iter() {
            let extension;
            if let Some(content_type) = &attachment.content_type {
                if content_type == "image/png" {
                    extension = "png";
                } else if content_type == "image/jpeg" {
                    extension = "jpg";
                } else {
                    invalid_types = true;
                    continue;
                }
            } else {
                invalid_types = true;
                continue;
            }
            requires_rebuild = true;
            let file_name = format!(
                "{}-{}-{}{}.{}",
                submission_data.len() + 1,
                slugify(&ctx.msg.author.name),
                ctx.msg.author.discriminator,
                if images.len() == 0 {
                    String::from("")
                } else {
                    format!("-{}", images.len() + 1)
                },
                extension
            );
            images.push(file_name.clone().into());
            let image = reqwest::get(&attachment.url).await?.bytes().await?;
            let mut image_file = File::create(format!("{}/{}", submission_images_dir, file_name))?;
            image_file.write_all(&image)?;
            image_file.flush()?;
        }
        submitter_data.insert(String::from("images"), images.into());
        submitter_data.insert(
            String::from("id"),
            ctx.msg.author.id.as_u64().to_string().into(),
        );
        submission_data.push(submitter_data.into());
    }
    set_submission_data(submission_data);
    let mut message = String::new();
    if requires_rebuild {
        message.push_str(&format!("Thank you for submitting! You can view your submission at <https://tegakituesday.com/{}>", challenge_number));
        if invalid_types {
            message.push_str("\nSome of your attachments could not be uploaded; only **.png**, **.jpg**, and **.jpeg** files are permitted.");
        }
        leaderboard(&ctx).await?;
        rebuild_site();
    } else if invalid_types {
        message.push_str("Sorry, your submission could not be uploaded; only **.png**, **.jpg**, and **.jpeg** files are permitted.");
    }
    ctx.msg.reply(&ctx.discord.http, message).await?;
    Ok(())
}

#[command(prefix_command, slash_command, description_localized("en-US", "List images in your current submission, if available."))]
pub async fn images(ctx: Context<'_>) -> Result<(), Error> {
    let submission_data = get_current_submission_data();
    let images: Vec<String> = {
        let mut images = Vec::new();
        for submission in submission_data.iter() {
            if is_matching_submission(&submission, &ctx.author()) {
                for image in submission["images"].as_array().unwrap().iter() {
                    images.push(String::from(image.as_str().unwrap()));
                }
                break;
            }
        }
        images
    };
    let challenge_number = get_challenge_number();
    if images.len() == 0 {
        ctx.say(
            format!(
                "You haven't submitted anything for Tegaki Tuesday #{}.",
                challenge_number
            ),
        )
        .await?;
        return Ok(());
    }
    let mut message = String::from(format!(
        "Your submission images for Tegaki Tuesday #{}:\n",
        challenge_number
    ));
    for (i, image) in images.iter().enumerate() {
        message.push_str(&format!(
            "（{}）<https://tegakituesday.com/{}/{}>\n",
            to_fullwidth(&(i + 1).to_string()),
            challenge_number,
            image
        ));
    }
    ctx.say(message).await?;
    Ok(())
}

#[command(prefix_command, slash_command, description_localized("en-US", "Delete images from your current submission using image numbers from the images command."))]
pub async fn imagedelete(
    ctx: Context<'_>,
    number: i32,
) -> Result<(), Error> {
    if number < 1 {
        ctx.say("That isn't a valid image number. Image numbers start at 1.").await?;
        return Ok(());
    }
    let challenge_number = get_challenge_number();
    let mut submission_data = get_current_submission_data();
    for (i, submission) in submission_data.iter_mut().enumerate() {
        if !is_matching_submission(&submission, &ctx.author()) {
            continue;
        }
        let mut images = submission["images"].as_array().unwrap().clone();
        let image_count = images.len();
        if image_count < number.try_into().unwrap() {
            ctx.say(
                if image_count == 0 {
                    // This is an edge case that should never happen.
                    // In this scenario, there is submission data with an empty image list.
                    // Submission data should be deleted uppon imageDelete if there are no images remaining.
                    format!(
                        "You haven't submitted anything for Tegaki Tuesday #{}.",
                        challenge_number
                    )
                } else {
                    format!(
                        "That image number doesn't exist, you only have {} image{}.",
                        image_count,
                        if image_count == 1 { "" } else { "s" }
                    )
                },
            )
            .await?;
            return Ok(());
        }
        let index = number as usize - 1;
        let image = images[index].as_str().unwrap().to_owned();
        let submission_images_dir = get_submission_images_dir();
        let image_path = format!("{}/{}", submission_images_dir, image);
        match fs::remove_file(image_path) {
            Ok(_) => (),
            // No need to worry about if the file is already missing
            Err(ref e) if e.kind() == std::io::ErrorKind::NotFound => (),
            Err(_) => panic!("Failed to remove file"),
        };
        let mut message = String::from(format!("Deleted **{}** from your submission.", image));
        if images.len() == 1 {
            message.push_str(" As there are no more images left attached to your submission, it has been deleted.");
            submission_data.remove(i);
        } else {
            images.remove(index);
            // One must rename all of the submitted images to prevent overwrites.
            // Consider the following scenario:
            // The submissions are ["bob-1234.png", "bob-1234-2.png"]
            // Bob uses the command imageDelete 1
            // The submissions become ["bob-1234-2.png"]
            // Bob makes a second submission
            // The submissions become ["bob-1234-2.png", "bob-1234-2.png"]
            // The original bob-1234-2.png gets overwriten,
            // and both submissions end up pointing to the same image.
            // In order to prevent this, images need to be renamed according to their index.
            for (j, image) in images.iter_mut().enumerate() {
                let old = image.as_str().unwrap();
                let from = format!("{}/{}", submission_images_dir, old);
                let author = ctx.author();
                let new = format!(
                    "{}-{}-{}{}.{}",
                    i + 1,
                    slugify(&author.name),
                    author.discriminator,
                    if j == 0 {
                        String::from("")
                    } else {
                        format!("-{}", j + 1)
                    },
                    Path::new(old).extension().unwrap().to_str().unwrap()
                );
                let to = format!("{}/{}", submission_images_dir, new);
                fs_extra::file::move_file(from, to, &fs_extra::file::CopyOptions::default())
                    .unwrap();
                *image = new.into();
            }
            submission["images"] = images.into();
        }
        set_submission_data(submission_data);
        rebuild_site();
        ctx.say(message).await?;
        return Ok(());
    }
    ctx.say(
        format!(
            "You haven't submitted anything for Tegaki Tuesday #{}.",
            challenge_number
        ),
    )
    .await?;
    Ok(())
}

// TODO: make also slash command
#[command(prefix_command, description_localized("en-US", "Make a suggestion for future challenge prompts!"))]
pub async fn suggest(
    ctx: PrefixContext<'_>,
    #[description = "Suggestion text. Please include passage and source."]
    suggestion: String,
) -> Result<(), Error> {
    let guild_data = get_guild_data();
    let channel = serenity::ChannelId(
        guild_data["suggestionChannel"]
            .as_str()
            .unwrap()
            .parse::<u64>()
            .unwrap(),
    );
    // User::accent_colour is only available via the REST API
    // If we just do msg.author.accent_colour here, we will get None
    let author = &ctx.msg.author;
    let accent_color = ctx.discord.http
        .get_user(*author.id.as_u64())
        .await
        .unwrap()
        .accent_colour;
    channel
        .send_message(&ctx.discord.http, |m| {
            m.allowed_mentions(|am| {
                am.empty_parse();
                am
            });
            m.embed(|e| {
                let username = format!("{}#{}", author.name, author.discriminator);
                e.title("New suggestion");
                e.description(format!(
                    "{}\n\n[See original message]({})",
                    suggestion,
                    ctx.msg.link(),
                ));
                let mut embed_author = serenity::builder::CreateEmbedAuthor::default();
                embed_author
                    .icon_url(get_avatar(&author))
                    .name(username)
                    .url(format!("https://discord.com/users/{}", author.id));
                e.set_author(embed_author);
                if let Some(accent_color) = accent_color {
                    e.color(accent_color);
                }
                e
            });
            m
        })
        .await
        .unwrap();
    ctx.msg.reply(&ctx.discord.http, "Suggestion sent! Thank you for making a suggestion. If it is chosen to be used in a future challenge, you will be mentioned in the challenge description!").await?;
    Ok(())
}