use chrono::prelude::Local;
use serde::{Deserialize, Serialize};
use tera::{Context, Tera};
use tide::http::mime;
use tide::{Redirect, Request, Response, Result, StatusCode};
use uuid::Uuid;

use std::env;

use crate::{fs, post::Post};

#[derive(Debug, Serialize, Deserialize)]
struct User {
    username: String,
    password: String,
}

pub async fn index(req: Request<()>) -> Result {
    let posts: Vec<Post> = fs::get_all_posts().await?;
    let mut context = Context::new();
    context.insert("posts", &posts);
    render_response("index.html", &context, &req)
}

pub async fn single_post(req: Request<()>) -> Result {
    let mut context = Context::new();
    let post_id = req.param("id")?;
    let post = fs::get_one_post(post_id).await?;
    context.insert("post", &post);
    render_response("single.html", &context, &req)
}

pub async fn edit_post(req: Request<()>) -> Result {
    let mut context = Context::new();
    let post_id = req.param("id")?;
    let mut post = fs::get_one_post(post_id).await?;
    post.body = post.body.replace("<br>", "\n");
    context.insert("post", &post);
    render_response("edit.html", &context, &req)
}

pub async fn create_post(mut req: Request<()>) -> Result {
    let mut post: Post = req.body_form().await?;
    post.id = Uuid::new_v4().to_string();
    post.date = Local::now().date().naive_local().to_string();
    post.body = post.body.trim().to_owned();
    post.save().await?;
    Ok(Redirect::new("/").into())
}

pub async fn update_post(mut req: Request<()>) -> Result {
    let mut post: Post = req.body_form().await?;
    post.save().await?;
    Ok(Redirect::new(format!("/posts/{}", post.id)).into())
}

pub async fn delete_post(req: Request<()>) -> Result {
    let id: String = req.param("id")?;
    fs::delete_post(id)?;
    let mut res = Response::new(StatusCode::Ok);
    res.set_body("{\"success\": \"true\"}");
    res.set_content_type(mime::JSON);
    Ok(res)
}

pub async fn login_page(mut req: Request<()>) -> Result {
    let mut context = Context::new();
    match req.session_mut().get::<String>("flash_error") {
        Some(error) => {
            req.session_mut().remove("flash_error");
            &context.insert("error", &error);
        }
        None => {}
    }
    render_response("login.html", &context, &req)
}

pub async fn login(mut req: Request<()>) -> Result {
    let username = env::var("ADMIN_USERNAME")?;
    let password = env::var("ADMIN_PASSWORD")?;
    let user: User = req.body_form().await?;
    if user.username == username && user.password == password {
        req.session_mut().remove("logged_in");
        req.session_mut().insert("logged_in", true)?;
        Ok(Redirect::new("/").into())
    } else {
        req.session_mut().remove("logged_in");
        req.session_mut()
            .insert("flash_error", "Invalid credentials")?;
        Ok(Redirect::new("/login").into())
    }
}

pub async fn logout(mut req: Request<()>) -> Result {
    req.session_mut().remove("logged_in");
    req.session_mut().insert("logged_in", false)?;
    Ok(Redirect::new("/").into())
}

pub fn render_response(template: &str, context: &Context, req: &Request<()>) -> Result<Response> {
    let mut context = context.clone();
    let logged_in: bool = req.session().get("logged_in").unwrap_or(false);
    context.insert("logged_in", &logged_in);
    let html = render_template(template, &context)?;
    let mut res = Response::new(StatusCode::Ok);
    res.set_body(html);
    res.set_content_type(mime::HTML);
    Ok(res)
}

pub fn render_template(template: &str, context: &Context) -> Result<String> {
    let tera = Tera::new("templates/**/*.html")?;
    let html = tera.render(template, &context)?;
    Ok(html)
}