use chrono::{Utc, NaiveDateTime};
use config::{Config, PrevPost, Secrets, CommunitiesVector, LemmyCommunities};
use lemmy_api_common::{
    person::{Login, LoginResponse},
    post::{CreatePost, GetPosts, GetPostsResponse, FeaturePost},
    sensitive::Sensitive, lemmy_db_views::structs::PostView,
};
use lemmy_db_schema::{
    ListingType, SortType, PostFeatureType, newtypes::CommunityId,
};
use once_cell::sync::Lazy;
use reqwest::{blocking::Client, StatusCode};
use std::{thread::sleep, time, collections::HashMap};

mod config;



pub static CLIENT: Lazy<Client> = Lazy::new(|| {
    let client = Client::builder()
        .timeout(time::Duration::from_secs(30))
        .connect_timeout(time::Duration::from_secs(30))
        .build()
        .expect("build client");
    client
});

struct Bot {
    secrets: Secrets,
    config: Config,
    post_history: Vec<PrevPost>,
    community_ids: CommunitiesVector,
    auth: Sensitive<String>,
    start_time: NaiveDateTime,
}

impl Bot {
    pub(crate) fn new() -> Bot {
        Bot {
            secrets: Secrets::init(),
            config: Config::init(),
            post_history: PrevPost::load(),
            community_ids: CommunitiesVector::new(),
            auth: Sensitive::new("".to_string()),
            start_time: Utc::now().naive_local(),
        }
    }

    /// Get JWT Token
    /// 
    /// * `return` : Returns true if token was succesfully retrieved, false otherwise
    #[warn(unused_results)]
    pub(crate) fn login(&mut self) -> Result<(), reqwest::Error> {
        let login_params = Login {
            username_or_email: self.secrets.lemmy.get_username(),
            password: self.secrets.lemmy.get_password(),
            totp_2fa_token: None,
        };

        let res = CLIENT
            .post(self.config.instance.clone() + "/api/v3/user/login")
            .json(&login_params)
            .send()?;
            

        if res.status() == StatusCode::OK {
            let data: &LoginResponse = &res.json().unwrap();

            let jwt = data.jwt.clone().expect("JWT Token could not be acquired");
            self.auth = jwt;
            return Ok(());
        } else {
            println!("Error Code: {:?}", res.status());
            return Err(res.error_for_status().unwrap_err());
        }
    }

    /// Make Post to Lemmy Instance
    /// 
    /// * `post_data` : Object of type [CreatePost] containing post info
    /// * `return` : Returns true if Post was succesful, false otherwise
    #[warn(unused_results)]
    pub(crate) fn post(&mut self, post_data: CreatePost) -> Result<PostView, reqwest::Error> {
        let res = CLIENT
            .post(self.config.instance.clone() + "/api/v3/post")
            .json(&post_data)
            .send()?;

        // TODO: process res to get info about if post was successfuly (mostly if jwt token was valid)   
        let ret: PostView = serde_json::from_str::<HashMap<&str, PostView>>(res.text()?.as_str()).unwrap().remove("post_view").unwrap();
        return Ok(ret);
    }

    #[warn(unused_results)]
    pub(crate) fn pin_new(&mut self, old_post: &Option<usize>, new_post: &PostView) -> Result<(), reqwest::Error> {
        match old_post {
            Some(id) => {
                let remove_community_pin = FeaturePost {
                    post_id: self.post_history[*id].post_id,
                    featured: false,
                    feature_type: PostFeatureType::Community,
                    auth: self.auth.clone()
                };

                let _ = self.pin(remove_community_pin);
            }
            None => {
                println!("Unable to unpin old post, please do so manually");
            }
        }

        // Unpin the other chapter post on local
        // Get all local pinned posts first
        // Filter out any post made in the meta community (Community ID)
        let get_params = GetPosts {
            auth: Some(self.auth.clone()),
            ..Default::default()
        };
        let post_list_json = CLIENT
            .get(self.config.instance.clone() + "/api/v3/post/list")
            .query(&get_params)
            .send()?
            .text()?;

        let post_list: GetPostsResponse = serde_json::from_str(post_list_json.as_str()).unwrap();

        let mut meta_community: CommunityId = CommunityId(15);

        self.community_ids.ids.iter().for_each(|(id, name)| {
            if name == &LemmyCommunities::metadiscussions.to_string() {
                meta_community = id.clone();
            }
        });

        for post_view in post_list.posts {
            if post_view.community.id != meta_community && post_view.post.featured_local {
                let remove_local_pin = FeaturePost {
                    post_id: post_view.post.id,
                    featured: false,
                    feature_type: PostFeatureType::Local,
                    auth: self.auth.clone()
                };
        
                let _ = self.pin(remove_local_pin);
            }
        }

        let pin_new_community = FeaturePost {
            post_id: new_post.post.id,
            featured: true,
            feature_type: PostFeatureType::Community,
            auth: self.auth.clone(),
        };

        let _ = self.pin(pin_new_community);

        let pin_new_local = FeaturePost {
            post_id: new_post.post.id,
            featured: true,
            feature_type: PostFeatureType::Local,
            auth: self.auth.clone(),
        };
    
        let _ = self.pin(pin_new_local);

        return Ok(());
    }

    pub(crate) fn pin (&mut self, pin_data: FeaturePost) -> Result<bool, reqwest::Error> {
        let res = CLIENT
            .post(self.config.instance.clone() + "/api/v3/post/feature")
            .json(&pin_data)
            .send()?;

        let ret: PostView = serde_json::from_str::<HashMap<&str, PostView>>(res.text()?.as_str()).unwrap().remove("post_view").unwrap();
        return Ok(ret.post.featured_local);
    }

    #[warn(unused_results)]
    pub(crate) fn run_once(&mut self, prev_time: &mut NaiveDateTime) -> Result<(), reqwest::Error> {
        println!("{:#<1$}", "", 30);
        self.start_time = Utc::now().naive_local();

        if self.start_time - *prev_time > chrono::Duration::seconds(6) { // Prod should use hours, add command line switch later and read duration from config
            println!("Reloading Config");
            *prev_time = self.start_time;
            self.config.load();
            self.community_ids.load(&self.auth, &self.config.instance)?;
            println!("Done!");
        }

        // Start the polling process
        // Get all feed URLs (use cache)
        println!("Checking Feeds");
        let post_queue: Vec<(CreatePost, (Option<usize>, usize, String))> = self.config.check_feeds(&mut self.post_history, &self.community_ids, &self.auth)?;
        println!("Done!");

        post_queue.iter().for_each(|(post, (prev_idx, feed_id, feed_title))| {
            println!("Posting: {}", post.name);

            let post_data: PostView;

            loop {
                let post_res = self.post(post.clone());
                if post_res.is_ok() {
                    post_data = post_res.unwrap();
                    break
                };
                println!("Post attempt failed, retrying");
            }

            loop {
                if self.pin_new(prev_idx, &post_data).is_ok() {break};
                println!("Pin attempt failed, retrying");
            }

            // Move current post to old post list
            match prev_idx {
                Some(idx) => {
                    self.post_history[*idx].title = feed_title.clone();
                    self.post_history[*idx].post_id = post_data.post.id;
                    self.post_history[*idx].last_post_url = post.url.clone().unwrap().to_string();
                }
                None => self.post_history.push(PrevPost {
                    id: feed_id.clone(),
                    post_id: post_data.post.id,
                    title: feed_title.clone(),
                    last_post_url: post.url.clone().unwrap().to_string(),
                }),
            }
        });

        PrevPost::save(&self.post_history);

        return Ok(());
    }

    pub(crate) fn idle(&self) {
        let mut sleep_duration = chrono::Duration::seconds(30);
        if Utc::now().naive_local() - self.start_time > sleep_duration {
            sleep_duration = chrono::Duration::seconds(60);
        }

        while Utc::now().naive_local() - self.start_time < sleep_duration {
            sleep(time::Duration::from_secs(1));
        }

        match reqwest::blocking::get("https://status.neshweb.net/api/push/7s1CjPPzrV?status=up&msg=OK&ping=") {
            Ok(_) => {},
            Err(err) => println!("{}", err)
        };
    } 

    pub(crate) fn print_info(&self) {
        print!("\x1B[2J\x1B[1;1H");
        println!("##[Ascendance of a Bookworm Bot]##");
        println!("Instance: {}", &self.config.instance);
        println!("Ran Last: {}", &self.start_time.format("%d/%m/%Y %H:%M:%S"));
        println!("{:#<1$}", "", 30);
        self.post_history.iter().for_each(|post| {
            print!("{} ", post.title);
            print!("{:<1$}: ", "", 60 - post.title.len());
            println!("{}",  post.last_post_url);
        })
    }
}

fn list_posts(auth: &Sensitive<String>, base: String) -> GetPostsResponse {
    let params = GetPosts {
        type_: Some(ListingType::Local),
        sort: Some(SortType::New),
        auth: Some(auth.clone()),
        ..Default::default()
    };

    let res = CLIENT
        .get(base + "/api/v3/post/list")
        .query(&params)
        .send()
        .unwrap()
        .text()
        .unwrap();

    return serde_json::from_str(&res).unwrap();
}

fn run_bot() {
    // Get all needed auth tokens at the start
    let mut old = Utc::now().naive_local();
    let mut this = Bot::new();
    match this.login() {
        Ok(_) => {
            let _ = this.community_ids.load(&this.auth, &this.config.instance);

            // Enter a loop (not for debugging)
            loop {
                this.idle();
                // 3 retries in case of connection issues
                let mut loop_breaker: u8 = 0;
                while !this.run_once(&mut old).is_ok() && loop_breaker <= 3 {
                    println!("Unable to complete Bot cycle, retrying with fresh login credentials");
                    if this.login().is_ok() {
                        let _ = this.community_ids.load(&this.auth, &this.config.instance);
                    }
                    sleep(time::Duration::from_secs(10));
                    loop_breaker += 1;
                };
                this.print_info();
                this.idle();
            }
        },
        Err(e) => {
            println!("Unable to get initial login:\n {:#?}", e);
        }
    }
}
fn main() {
    run_bot();
}