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,
    ephemeral,
    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,
    slash_command,
    ephemeral,
    broadcast_typing,
    description_localized("en-US", "Submit to the latest handwriting challenge.")
)]
pub async fn submit(ctx: Context<'_>, submission: serenity::Attachment) -> Result<(), Error> {
    // TODO: The code for this command needs to be refactored,
    // there are large duplicated sections that need to be merged somehow.
    match ctx {
        Context::Application(_) => ctx.defer_ephemeral().await?,
        Context::Prefix(ctx) => {
            if ctx.msg.attachments.len() == 0 {
                ctx.msg
                    .reply(&ctx.discord.http, "Please attach at least one image.")
                    .await?;
                return Ok(());
            }
        }
    }
    let guild_data = get_guild_data();
    let guild = ctx.guild_id().unwrap().as_u64().to_string();
    if !guild_data.contains_key(&guild)
        || !&guild_data[&guild]
            .as_object()
            .unwrap()
            .contains_key("submissionChannel")
    {
        ctx.say("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.channel_id().as_u64().to_string() {
        ctx.defer_ephemeral().await?;
        ctx.say(format!(
            "Sorry, submissions aren't permitted here. Please go to <#{}>. Thanks!",
            guild
        ))
        .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;
    let attachments = vec![submission];
    let attachments = match ctx {
        Context::Application(_) => &attachments,
        Context::Prefix(ctx) => &ctx.msg.attachments,
    };
    let author = ctx.author();
    let mut submitted_images = Vec::new();
    for (i, submission) in submission_data.iter_mut().enumerate() {
        if is_matching_submission(&submission, author) {
            existing_submitter = true;
            let images: Vec<String> = submission["images"].as_array_mut().unwrap().clone().iter().map(|value| value.as_str().unwrap().to_owned()).collect();
            for attachment in 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(&author.name),
                    author.discriminator,
                    images.len() + 1,
                    extension
                );
                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()?;
                submitted_images.push(file_name);
            }
            submission["images"] = images.clone().into();
            break;
        }
    }
    if !existing_submitter {
        let mut submitter_data = Map::new();
        submitter_data.insert(
            String::from("username"),
            format!("{}#{}", author.name, author.discriminator).into(),
        );
        let mut images: Vec<String> = Vec::new();
        for attachment in 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(&author.name),
                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()?;
            submitted_images.push(file_name);
        }
        submitter_data.insert(String::from("images"), images.into());
        submitter_data.insert(String::from("id"), 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 {
        let thank_you = &format!("Thank you for submitting! You can view your submission at <https://tegakituesday.com/{}>", challenge_number);
        let mut repost_here = true;
        match ctx {
            Context::Application(_) => message.push_str(thank_you),
            Context::Prefix(ctx) => match ctx.msg.delete(&ctx.discord.http).await {
                Ok(_) => {}
                // don't repost image on this server if no manage messages perm
                // (if we can't delete user's image it'll be displayed twice)
                Err(_) => {
                    repost_here = false;
                    message.push_str(thank_you);
                }
            },
        };
        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();
        let guild = ctx.guild().unwrap();
        let data = guild_data[&guild.id.to_string()].as_object().unwrap();
        let invite = if data.contains_key("invite") {
            Some(data["invite"].as_str().unwrap())
        } else {
            None };
        for image in submitted_images.iter() {
            for (other_guild_id, data) in guild_data.iter() {
                let here = other_guild_id.eq(&ctx.guild_id().unwrap().as_u64().to_string());
                if !repost_here && here {
                    continue;
                }
                let data = data.as_object().unwrap();
                if !data.contains_key("submissionChannel") {
                    continue;
                }
                let channel = serenity::ChannelId(
                    data["submissionChannel"]
                        .as_str()
                        .unwrap()
                        .parse::<u64>()
                        .unwrap(),
                );
                let accent_color = ctx
                    .discord()
                    .http
                    .get_user(*author.id.as_u64())
                    .await
                    .unwrap()
                    .accent_colour;
                let mut pathbuf = std::path::PathBuf::new();
                pathbuf.push(&submission_images_dir);
                pathbuf.push(&image);
                channel.send_message(&ctx.discord().http, |m| {
                    m.add_file(&pathbuf);
                    m.embed(|e| {
                        let username = format!("{}#{}", author.name, author.discriminator);
                        let n = get_challenge_number();
                        let mut description = format!("New submission to [Tegaki Tuesday #{n}](https://tegakituesday.com/{n})!");
                        if !here {
                            description.push_str(&if let Some(invite) = invite {
                                format!("\nCrossposted from [{}](https://discord.gg/{invite})", guild.name)
                            } else {
                                format!("\nCrossposted from {}", guild.name)
                            });
                        };
                        e.description(description);
                        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);
                        e.image(format!("attachment://{image}"));
                        if let Some(accent_color) = accent_color {
                            e.color(accent_color);
                        }
                        e
                    });
                    m
                }).await?;
            }
        }
    } else if invalid_types {
        message.push_str("Sorry, your submission could not be uploaded; only **.png**, **.jpg**, and **.jpeg** files are permitted.");
    }
    if !message.is_empty() {
        ctx.say(message).await?;
    }
    Ok(())
}

#[command(
    prefix_command,
    slash_command,
    ephemeral,
    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,
    ephemeral,
    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(())
}