use cursive::{
    event::Key,
    menu::MenuTree,
    theme::{Effect, Style, Color, PaletteColor, Theme},
    traits::*,
    utils::markup::StyledString,
    views::{Dialog, EditView, Panel, ResizedView, TextView},
    Cursive,
};
use maj::{self, Response, StatusCode};
use std::str;

fn main() {
    cursive::logger::init();

    let mut siv = cursive::default();

    let theme = custom_theme_from_cursive(&siv);
    siv.set_theme(theme);

    siv.add_global_callback('c', |s| {
        s.pop_layer();
    });
    siv.add_global_callback('q', cursive::Cursive::quit);
    siv.add_global_callback('~', cursive::Cursive::toggle_debug_console);
    siv.add_global_callback('o', open_prompt);
    siv.add_global_callback('?', help);

    siv.menubar()
        .add_subtree(
            "majc",
            MenuTree::new()
                .leaf("About", move |s| {
                    s.add_layer(Dialog::info(format!(
                        "{} {}\n\nby {}\n\nSee https://tulpa.dev/cadey/maj for more information",
                        env!("CARGO_PKG_NAME"),
                        env!("CARGO_PKG_VERSION"),
                        env!("CARGO_PKG_AUTHORS"),
                    )));
                })
                .leaf("Help", move |s| {
                    help(s);
                }),
        )
        .add_leaf("Open", |s| open_prompt(s));

    siv.set_autohide_menu(false);
    siv.add_global_callback(Key::Esc, |s| s.select_menubar());

    help(&mut siv);

    siv.run();
}

fn help(siv: &mut Cursive) {
    let content = include_str!("./help.gmi");

    siv.add_layer(
        Dialog::around(Panel::new(
            TextView::new(render_gemini(content)).scrollable(),
        ))
        .title("Help")
        .dismiss_button("Ok"),
    );
}

fn open_prompt(siv: &mut Cursive) {
    siv.add_layer(
        Dialog::around(
            EditView::new()
                .on_submit(open)
                .with_name("url")
                .fixed_width(50),
        )
        .title("Enter a Gemini URL")
        .button("Ok", |s| {
            let url = s
                .call_on_name("url", |view: &mut EditView| view.get_content())
                .unwrap();
            open(s, &url);
        })
        .button("Cancel", |s| {
            s.pop_layer();
        }),
    );
}

fn open(siv: &mut Cursive, url: &str) {
    siv.pop_layer();
    log::debug!("got URL: {}", url);

    match maj::get(url.to_string()) {
        Ok(resp) => {
            show(siv, url, resp);
        }
        Err(why) => {
            log::error!("got response error: {:?}", why);
            siv.add_layer(Dialog::info(format!("Error fetching response: {:?}", why)));
        }
    }
}

fn show(siv: &mut Cursive, url: &str, resp: Response) {
    use StatusCode::*;

    match resp.status {
        Success => match str::from_utf8(&resp.body) {
            Ok(content) => {
                let content: StyledString = if resp.meta.starts_with("text/gemini") {
                    render_gemini(content)
                } else {
                    StyledString::plain(content)
                };
                siv.add_fullscreen_layer(ResizedView::with_full_screen(
                    Dialog::around(TextView::new(content).scrollable())
                        .title(format!("{}: {}", url, resp.meta)),
                ));
            }
            Err(why) => {
                siv.add_layer(Dialog::info(format!(
                    "UTF/8 decoding error for {}: {:?}",
                    url, why
                )));
            }
        },

        TemporaryRedirect => {
            open(siv, resp.meta.as_str());
        }

        PermanentRedirect => {
            open(siv, resp.meta.as_str());
        }

        Input => {
            siv.add_layer(Dialog::info("needs input support"));
            return;
            // siv.add_layer(
            //     Dialog::around(EditView::new().with_name("input").fixed_width(50))
            //         .title(resp.meta)
            //         .button("Ok", |s| {
            //             let inp = s
            //                 .call_on_name("input", |view: &mut EditView| view.get_content())
            //                 .unwrap();
            //             let url = {
            //                 let mut u = url::Url::parse(url).unwrap();
            //                 u.set_query(Some(&inp));
            //                 u.as_str()
            //             };
            //             open(s, url);
            //         }),
            // );
        }

        _ => {
            siv.add_layer(Dialog::info(format!("{:?}: {}", resp.status, resp.meta)));
            return;
        }
    }
}

fn render_gemini(body: &str) -> StyledString {
    let doc = maj::gemini::parse(body);
    let mut styled = StyledString::new();

    use maj::gemini::Node::*;

    for node in doc {
        match node {
            Text(line) => styled.append(StyledString::plain(line)),
            Link { to, name } => match name {
                None => styled.append(StyledString::styled(to, Style::from(Effect::Underline))),
                Some(name) => styled.append(StyledString::styled(
                    format!("{}: {}", to, name),
                    Style::from(Effect::Underline),
                )),
            },
            Preformatted(data) => styled.append(StyledString::plain(data)),
            Heading { level: _, body } => {
                styled.append(StyledString::styled(body, Style::from(Effect::Bold)))
            }
            ListItem(item) => styled.append(StyledString::plain(format!("* {}", item))),
            Quote(quote) => styled.append(StyledString::plain(format!("> {}", quote))),
        }
        styled.append(StyledString::plain("\n"));
    }

    styled
}

fn custom_theme_from_cursive(siv: &Cursive) -> Theme {
    // We'll return the current theme with a small modification.
    let mut theme = siv.current_theme().clone();

    theme.palette[PaletteColor::Background] = Color::TerminalDefault;

    theme
}