use core::time::Duration;
use std::sync::{Arc, Mutex, MutexGuard};

use cpclib_common::itertools::Itertools;

#[cfg(feature = "indicatif")]
use indicatif::{MultiProgress, ProgressBar, ProgressStyle};



lazy_static::lazy_static! {
    static ref PROGRESS: Arc<Mutex<Progress>> = Arc::new(Mutex::new(Progress::new()));
}

const REFRESH_RATE: Duration = Duration::from_millis(250);
const PROGRESS_STYLE: &'static str = "{prefix:.bold.dim>8}  [{bar}] {pos:>3}/{len:3} {wide_msg}";
const PASS_STYLE: &'static str = "{prefix:.bold.dim>8}  [{bar}] ";

#[cfg(feature = "indicatif")]
pub struct Progress {
    multi: MultiProgress,
    parse: CountedProgress,
    load: CountedProgress,
    save: Option<CountedProgress>,
    pass: Option<(usize, ProgressBar)>
}

#[cfg(not(feature = "indicatif"))]
pub struct Progress {
    parse: CountedProgress,
    load: CountedProgress,
    save: Option<CountedProgress>,
    pass: Option<(usize, usize, usize)>, // pass, nb ivisited, nb to do
}

pub fn normalize(path: &std::path::Path) -> &str {
    path.file_name().unwrap().to_str().unwrap()
}

#[cfg(feature = "indicatif")]
//TODO add the multiprogess bar as a field and never pass it as an argument
// it will allow to reduce duplicated code with indicatf/no indicatif versions
struct CountedProgress {
    bar: Option<ProgressBar>,
    current_items: hashbag::HashBag<String>,
    nb_expected: u64,
    nb_done: u64,
    prefix: &'static str,
    index: usize,
    freeze_amount: bool
}

#[cfg(not(feature = "indicatif"))]
struct CountedProgress {
    current_items: hashbag::HashBag<String>,
    nb_expected: u64,
    nb_done: u64,
    prefix: &'static str,
    index: usize,
    freeze_amount: bool,
    last_tick: std::time::SystemTime
}


#[cfg(feature = "indicatif")]
impl CountedProgress {
    pub fn new(kind: &'static str, index: usize, freeze_amount: bool) -> Self {
        let cp = CountedProgress {
            bar: None,
            current_items: hashbag::HashBag::new(),
            nb_done: 0,
            nb_expected: 0,
            prefix: kind,
            index,
            freeze_amount,
        };
        cp
    }

    fn add_item(&mut self, item: &str, multi: &MultiProgress) {
        if !self.freeze_amount {
            self.nb_expected += 1;
        }
        self.current_items.insert(item.into());
        self.update_visual(multi);
    }

    fn add_items<'a>(&mut self, items: impl Iterator<Item = &'a str>, multi: &MultiProgress) {
        let mut count = 0;
        for item in items {
            self.current_items.insert(String::from(item));
            count += 1;
        }

        if !self.freeze_amount {
            self.nb_expected += count;
        }
        self.update_visual(multi);
    }

    fn remove_item(&mut self, item: &str, multi: &MultiProgress) {
        self.nb_done += 1;
        self.current_items.remove(item);
        self.update_visual(multi);
    }

    fn finished(&mut self) {
        self.bar.as_mut().map(|bar| bar.finish());
    }

    fn update_visual(&mut self, multi: &MultiProgress) {
        let visible = self.bar.is_some();

        if self.nb_done == self.nb_expected {
            if visible {
                self.bar.as_ref().map(|bar| {
                    bar.set_message("");
                    bar.set_position(self.nb_done);
                    bar.set_length(self.nb_expected);

                    bar.tick();

                    // multi.remove(bar);
                });
                // self.bar = None;
            }
        }
        else {
            let content = self.current_items.iter().join(", ");

            if !visible {
                self.bar = Some(multi.add(ProgressBar::new(self.nb_expected)));
                self.bar.as_ref().map(|bar| {
                    bar.set_style(
                        ProgressStyle::with_template(PROGRESS_STYLE)
                            .unwrap()
                            .progress_chars("=> ")
                    );
                    bar.set_prefix(self.prefix);
                });
            }

            self.bar.as_ref().map(|bar| {
                bar.set_message(content);
                bar.set_position(self.nb_done);
                bar.set_length(self.nb_expected);
                bar.tick();
            });
        }
    }
}


#[cfg(not(feature = "indicatif"))]
impl CountedProgress {
    pub fn new(kind: &'static str, index: usize, freeze_amount: bool) -> Self {
        let cp = CountedProgress {
            current_items: hashbag::HashBag::new(),
            nb_done: 0,
            nb_expected: 0,
            prefix: kind,
            index,
            freeze_amount,
            last_tick: std::time::SystemTime::now()
        };
        cp
    }

    fn add_item(&mut self, item: &str) {
        if !self.freeze_amount {
            self.nb_expected += 1;
        }
        self.current_items.insert(item.into());
        self.update_visual();
    }

    fn add_items<'a>(&mut self, items: impl Iterator<Item = &'a str>) {
        let mut count = 0;
        for item in items {
            self.current_items.insert(String::from(item));
            count += 1;
        }

        if !self.freeze_amount {
            self.nb_expected += count;
        }
        self.update_visual();
    }

    fn remove_item(&mut self, item: &str) {
        self.nb_done += 1;
        self.current_items.remove(item);
        self.update_visual();
    }

    fn finished(&mut self) {
    }

    fn update_visual(&mut self) {

        const HZ:u128 = 1000/15;

        if self.last_tick.elapsed().unwrap().as_millis() >= HZ {

            self.really_show();

            self.last_tick = std::time::SystemTime::now();

        }

    }

    fn really_show(&self) {

        let content = self.current_items.iter().join(", ");
        let other_content = &content[..70.min(content.len())];
        let extra = if other_content.len() != content.len() {
            "..."
        } else {
            ""
        };

        println!("{} [{}/{}] {}{}", self.prefix, self.nb_done, self.nb_expected, other_content, extra);
    }

}


#[cfg(feature = "indicatif")]
fn new_spinner() -> ProgressBar {
    let bar = ProgressBar::new_spinner();

    bar.set_style(
        ProgressStyle::with_template("{spinner:.blue} {msg}")
            // For more spinners check out the cli-spinners project:
            // https://github.com/sindresorhus/cli-spinners/blob/master/spinners.json
            .unwrap()
            .tick_strings(&[
                "▹▹▹▹▹",
                "▸▹▹▹▹",
                "▹▸▹▹▹",
                "▹▹▸▹▹",
                "▹▹▹▸▹",
                "▹▹▹▹▸",
                "▪▪▪▪▪"
            ])
    );
    bar.enable_steady_tick(REFRESH_RATE);
    bar
}

impl Progress {
    pub fn progress() -> MutexGuard<'static, Progress> {
        PROGRESS.lock().unwrap()
    }

    #[cfg(feature = "indicatif")]
    pub fn new() -> Self {
        let multi = MultiProgress::new();
        multi.set_move_cursor(true);

        Progress {
            multi,
            load: CountedProgress::new("  Load", 0, false),
            parse: CountedProgress::new(" Parse", 1, false),
            save: None,
            pass: None
        }
    }

    #[cfg(not(feature = "indicatif"))]
    pub fn new() -> Self {
        Progress {
            load: CountedProgress::new("  Load", 0, false),
            parse: CountedProgress::new(" Parse", 1, false),
            save: None,
            pass: None           
        }
    }

    pub fn add_parse(&mut self, ident: &str) {
        #[cfg(feature = "indicatif")]
        self.parse.add_item(ident, &self.multi);

        #[cfg(not(feature = "indicatif"))]
        self.parse.add_item(ident);
    }

    pub fn add_parses<'a>(&mut self, items: impl Iterator<Item = &'a str>) {
        #[cfg(feature = "indicatif")]
        self.parse.add_items(items, &self.multi);

        #[cfg(not(feature = "indicatif"))]
        self.parse.add_items(items);
    }

    pub fn remove_parse(&mut self, ident: &str) {
        #[cfg(feature = "indicatif")]
        self.parse.remove_item(ident, &self.multi);

        #[cfg(not(feature = "indicatif"))]
        self.parse.remove_item(ident);
    }

    pub fn add_load(&mut self, ident: &str) {
        #[cfg(feature = "indicatif")]
        self.load.add_item(ident, &self.multi);

        #[cfg(not(feature = "indicatif"))]
        self.load.add_item(ident);
    }

    pub fn add_loads<'a>(&mut self, items: impl Iterator<Item = &'a str>) {
        #[cfg(feature = "indicatif")]
        self.load.add_items(items, &self.multi);

        #[cfg(not(feature = "indicatif"))]
        self.load.add_items(items);
    }

    pub fn remove_load(&mut self, ident: &str) {
        #[cfg(feature = "indicatif")]
        self.load.remove_item(ident, &self.multi);

        #[cfg(not(feature = "indicatif"))]
        self.load.remove_item(ident);
    }

    #[cfg(feature = "indicatif")]
    pub fn new_pass(&mut self) {
        if self.pass.is_none() {
            let bar = ProgressBar::new(0);
            bar.set_style(
                ProgressStyle::with_template(PASS_STYLE)
                    .unwrap()
                    .progress_chars("=> ")
            );
            self.pass = Some((0, self.multi.add(bar)));
        }
        else {
            // todo change pass numbering
        }

        self.pass.as_mut().map(|(pass, bar)| {
            *pass += 1;
            bar.set_prefix(format!("Pass {}", *pass));
            bar.set_position(0);
            bar.set_length(0);
        });
    }

    #[cfg(not(feature = "indicatif"))]
    pub fn new_pass(&mut self) {
        if self.pass.is_none() {
            self.pass = Some((0, 0, 0));
        }

        self.pass.as_mut().map(|pass: &mut (usize, usize, usize) | *pass = (pass.0+1, 0, 0));
    }

    #[cfg(feature = "indicatif")]
    pub fn add_visited_to_pass(&mut self, amount: u64) {
        self.pass.as_mut().unwrap().1.inc(amount);
    }

    #[cfg(not(feature = "indicatif"))]
    pub fn add_visited_to_pass(&mut self, amount: u64) {
        self.pass.as_mut().unwrap().1 += amount as usize;
    }

    #[cfg(feature = "indicatif")]
    pub fn add_expected_to_pass(&mut self, amount: u64) {
        self.pass.as_mut().unwrap().1.inc_length(amount);
    }

    #[cfg(not(feature = "indicatif"))]
    pub fn add_expected_to_pass(&mut self, amount: u64) {
        self.pass.as_mut().unwrap().2 += amount as usize;
    }

    pub fn create_save_bar(&mut self, amount: u64) {
        let mut bar = CountedProgress::new("  Save", 2, true);
        bar.nb_expected = amount;
        self.save = Some(bar);
    }

    pub fn add_save(&mut self, ident: &str) {
        #[cfg(feature = "indicatif")]
        self.save.as_mut().unwrap().add_item(ident, &self.multi);

        #[cfg(not(feature = "indicatif"))]
        self.save.as_mut().unwrap().add_item(ident);
    }

    pub fn remove_save(&mut self, ident: &str) {
        #[cfg(feature = "indicatif")]
        self.save.as_mut().unwrap().remove_item(ident, &self.multi);

        #[cfg(not(feature = "indicatif"))]
        self.save.as_mut().unwrap().remove_item(ident);
    }

    pub fn finish_save(&mut self) {
        self.save.as_mut().unwrap().finished();
    }

    /// Add the progress bar for a file to read
    #[cfg(feature = "indicatif")]
    pub fn add_bar(&self, msg: &str) -> ProgressBar {
        let bar = new_spinner();
        let bar = self.multi.add(bar);
        bar.set_message(msg.to_owned());
        bar
    }

    #[cfg(feature = "indicatif")]
    /// Remove the progress bar of the current file
    pub fn remove_bar_ok(&self, bar: &ProgressBar) {
        bar.disable_steady_tick();
        bar.finish_and_clear();
        bar.tick();
        self.multi.remove(bar);
    }

    #[cfg(feature = "indicatif")]
    pub fn remove_bar_err(&self, bar: &ProgressBar, msg: &str) {
        bar.disable_steady_tick();
        bar.abandon_with_message(msg.to_owned());
        bar.tick();
        self.multi.remove(bar);
    }
}