/*
 * meli
 *
 * Copyright 2017-2018 Manos Pitsidianakis
 *
 * This file is part of meli.
 *
 * meli is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * meli is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with meli. If not, see <http://www.gnu.org/licenses/>.
 */

use super::*;
use melib::list_management;

use crate::terminal::embed::EmbedGrid;
use melib::Draft;
use nix::sys::wait::WaitStatus;
use std::str::FromStr;
use std::sync::{Arc, Mutex};
use xdg_utils::query_mime_info;

#[derive(Debug, PartialEq)]
enum Cursor {
    Headers,
    Body,
    //Attachments,
}

#[derive(Debug)]
enum EmbedStatus {
    Stopped(Arc<Mutex<EmbedGrid>>, File),
    Running(Arc<Mutex<EmbedGrid>>, File),
}

impl std::ops::Deref for EmbedStatus {
    type Target = Arc<Mutex<EmbedGrid>>;
    fn deref(&self) -> &Arc<Mutex<EmbedGrid>> {
        use EmbedStatus::*;
        match self {
            Stopped(ref e, _) | Running(ref e, _) => e,
        }
    }
}

impl std::ops::DerefMut for EmbedStatus {
    fn deref_mut(&mut self) -> &mut Arc<Mutex<EmbedGrid>> {
        use EmbedStatus::*;
        match self {
            Stopped(ref mut e, _) | Running(ref mut e, _) => e,
        }
    }
}

#[derive(Debug)]
pub struct Composer {
    reply_context: Option<(FolderHash, EnvelopeHash)>,
    account_cursor: usize,

    cursor: Cursor,

    pager: Pager,
    draft: Draft,
    form: FormWidget,

    mode: ViewMode,

    embed_area: Area,
    embed: Option<EmbedStatus>,
    sign_mail: ToggleFlag,
    dirty: bool,
    has_changes: bool,
    initialized: bool,
    id: ComponentId,
}

impl Default for Composer {
    fn default() -> Self {
        let mut pager = Pager::default();
        pager.set_reflow(text_processing::Reflow::FormatFlowed);
        Composer {
            reply_context: None,
            account_cursor: 0,

            cursor: Cursor::Headers,

            pager,
            draft: Draft::default(),
            form: FormWidget::default(),

            mode: ViewMode::Edit,
            sign_mail: ToggleFlag::Unset,
            dirty: true,
            has_changes: false,
            embed_area: ((0, 0), (0, 0)),
            embed: None,
            initialized: false,
            id: ComponentId::new_v4(),
        }
    }
}

#[derive(Debug)]
enum ViewMode {
    Discard(Uuid, Selector<char>),
    Edit,
    Embed,
    SelectRecipients(Selector<Address>),
    Send(Selector<bool>),
}

impl ViewMode {
    fn is_edit(&self) -> bool {
        if let ViewMode::Edit = self {
            true
        } else {
            false
        }
    }
}

impl fmt::Display for Composer {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        // TODO display subject/info
        if self.reply_context.is_some() {
            write!(f, "reply: {:8}", self.draft.headers()["Subject"])
        } else {
            write!(f, "composing")
        }
    }
}

impl Composer {
    const DESCRIPTION: &'static str = "composing";
    pub fn new(account_cursor: usize) -> Self {
        Composer {
            account_cursor,
            id: ComponentId::new_v4(),
            ..Default::default()
        }
    }

    pub fn edit(account_pos: usize, h: EnvelopeHash, context: &Context) -> Result<Self> {
        let mut ret = Composer::default();
        let op = context.accounts[account_pos].operation(h);
        let envelope: EnvelopeRef = context.accounts[account_pos].collection.get_env(h);

        ret.draft = Draft::edit(&envelope, op)?;

        ret.account_cursor = account_pos;
        Ok(ret)
    }

    pub fn with_context(
        coordinates: (usize, FolderHash),
        msg: EnvelopeHash,
        context: &Context,
    ) -> Self {
        let account = &context.accounts[coordinates.0];
        let mut ret = Composer::default();
        let parent_message = account.collection.get_env(msg);
        /* If message is from a mailing list and we detect a List-Post header, ask user if they
         * want to reply to the mailing list or the submitter of the message */
        if let Some(actions) = list_management::ListActions::detect(&parent_message) {
            if let Some(post) = actions.post {
                if let list_management::ListAction::Email(list_post_addr) = post[0] {
                    if let Ok(list_address) = melib::email::parser::mailto(list_post_addr)
                        .to_full_result()
                        .map(|m| m.address)
                    {
                        let list_address_string = list_address.to_string();
                        ret.mode = ViewMode::SelectRecipients(Selector::new(
                            "select recipients",
                            vec![
                                (
                                    parent_message.from()[0].clone(),
                                    parent_message.field_from_to_string(),
                                ),
                                (list_address, list_address_string),
                            ],
                            false,
                            context,
                        ));
                    }
                }
            }
        }

        let mut op = account.operation(msg);
        let parent_bytes = op.as_bytes();

        ret.draft = Draft::new_reply(&parent_message, parent_bytes.unwrap());
        let subject = parent_message.subject();
        ret.draft.headers_mut().insert(
            "Subject".into(),
            if !subject.starts_with("Re: ") {
                format!("Re: {}", subject)
            } else {
                subject.into()
            },
        );

        ret.account_cursor = coordinates.0;
        ret.reply_context = Some((coordinates.1, msg));
        ret
    }

    pub fn set_draft(&mut self, draft: Draft) {
        self.draft = draft;
        self.update_form();
    }

    fn update_draft(&mut self) {
        let header_values = self.form.values_mut();
        let draft_header_map = self.draft.headers_mut();
        for (k, v) in draft_header_map.iter_mut() {
            if let Some(ref vn) = header_values.get(k) {
                *v = vn.as_str().to_string();
            }
        }
    }

    fn update_form(&mut self) {
        let old_cursor = self.form.cursor();
        self.form = FormWidget::new("Save".into());
        self.form.hide_buttons();
        self.form.set_cursor(old_cursor);
        let headers = self.draft.headers();
        let account_cursor = self.account_cursor;
        for &k in &["Date", "From", "To", "Cc", "Bcc", "Subject"] {
            if k == "To" || k == "Cc" || k == "Bcc" {
                self.form.push_cl((
                    k.into(),
                    headers[k].to_string(),
                    Box::new(move |c, term| {
                        let book: &AddressBook = &c.accounts[account_cursor].address_book;
                        let results: Vec<String> = book.search(term);
                        results
                            .into_iter()
                            .map(|r| AutoCompleteEntry::from(r))
                            .collect::<Vec<AutoCompleteEntry>>()
                    }),
                ));
            } else {
                self.form.push((k.into(), headers[k].to_string()));
            }
        }
    }

    fn draw_attachments(&self, grid: &mut CellBuffer, area: Area, context: &Context) {
        let attachments_no = self.draft.attachments().len();
        clear_area(grid, area);
        if self.sign_mail.is_true() {
            write_string_to_grid(
                &format!(
                    "☑ sign with {}",
                    context
                        .settings
                        .pgp
                        .key
                        .as_ref()
                        .map(String::as_str)
                        .unwrap_or("default key")
                ),
                grid,
                Color::Default,
                Color::Default,
                Attr::Default,
                (pos_inc(upper_left!(area), (0, 1)), bottom_right!(area)),
                None,
            );
        } else {
            write_string_to_grid(
                "☐ don't sign",
                grid,
                Color::Default,
                Color::Default,
                Attr::Default,
                (pos_inc(upper_left!(area), (0, 1)), bottom_right!(area)),
                None,
            );
        }
        if attachments_no == 0 {
            write_string_to_grid(
                "no attachments",
                grid,
                Color::Default,
                Color::Default,
                Attr::Default,
                (pos_inc(upper_left!(area), (0, 2)), bottom_right!(area)),
                None,
            );
        } else {
            write_string_to_grid(
                &format!("{} attachments ", attachments_no),
                grid,
                Color::Default,
                Color::Default,
                Attr::Default,
                (pos_inc(upper_left!(area), (0, 2)), bottom_right!(area)),
                None,
            );
            for (i, a) in self.draft.attachments().iter().enumerate() {
                if let Some(name) = a.content_type().name() {
                    write_string_to_grid(
                        &format!(
                            "[{}] \"{}\", {} {} bytes",
                            i,
                            name,
                            a.content_type(),
                            a.raw.len()
                        ),
                        grid,
                        Color::Default,
                        Color::Default,
                        Attr::Default,
                        (pos_inc(upper_left!(area), (0, 3 + i)), bottom_right!(area)),
                        None,
                    );
                } else {
                    write_string_to_grid(
                        &format!("[{}] {} {} bytes", i, a.content_type(), a.raw.len()),
                        grid,
                        Color::Default,
                        Color::Default,
                        Attr::Default,
                        (pos_inc(upper_left!(area), (0, 3 + i)), bottom_right!(area)),
                        None,
                    );
                }
            }
        }
    }
}

impl Component for Composer {
    fn draw(&mut self, grid: &mut CellBuffer, area: Area, context: &mut Context) {
        let upper_left = upper_left!(area);
        let bottom_right = bottom_right!(area);

        let upper_left = set_y(upper_left, get_y(upper_left) + 1);

        if height!(area) < 4 {
            return;
        }

        let width = width!(area);

        if !self.initialized {
            if self.sign_mail.is_unset() {
                self.sign_mail = ToggleFlag::InternalVal(context.settings.pgp.auto_sign);
            }
            if !self.draft.headers().contains_key("From") || self.draft.headers()["From"].is_empty()
            {
                self.draft.headers_mut().insert(
                    "From".into(),
                    crate::components::mail::get_display_name(context, self.account_cursor),
                );
            }
            self.pager.update_from_str(self.draft.body(), Some(77));
            self.update_form();
            self.initialized = true;
        }
        let header_height = self.form.len();

        let mid = if width > 80 {
            let width = width - 80;
            let mid = width / 2;

            if self.dirty {
                for i in get_y(upper_left)..=get_y(bottom_right) {
                    //set_and_join_box(grid, (mid, i), VERT_BOUNDARY);
                    grid[(mid, i)].set_fg(Color::Default);
                    grid[(mid, i)].set_bg(Color::Default);
                    //set_and_join_box(grid, (mid + 80, i), VERT_BOUNDARY);
                    grid[(mid + 80, i)].set_fg(Color::Default);
                    grid[(mid + 80, i)].set_bg(Color::Default);
                }
            }
            mid
        } else {
            0
        };

        let header_area = (
            set_x(upper_left, mid + 1),
            (
                get_x(bottom_right).saturating_sub(mid),
                get_y(upper_left) + header_height,
            ),
        );
        let attachments_no = self.draft.attachments().len();
        let attachment_area = (
            (mid + 1, get_y(bottom_right) - 2 - attachments_no),
            pos_dec(bottom_right, (mid, 0)),
        );

        let body_area = (
            pos_inc(upper_left, (mid + 1, header_height + 1)),
            pos_dec(bottom_right, (mid, 3 + attachments_no)),
        );

        let (x, y) = write_string_to_grid(
            if self.reply_context.is_some() {
                "COMPOSING REPLY"
            } else {
                "COMPOSING MESSAGE"
            },
            grid,
            Color::Byte(189),
            Color::Byte(167),
            Attr::Default,
            (
                pos_dec(upper_left!(header_area), (0, 1)),
                bottom_right!(header_area),
            ),
            None,
        );
        clear_area(grid, ((x, y), (set_y(bottom_right, y))));
        change_colors(
            grid,
            (
                set_x(pos_dec(upper_left!(header_area), (0, 1)), x),
                set_y(bottom_right!(header_area), y),
            ),
            Color::Byte(189),
            Color::Byte(167),
        );
        if mid != 0 {
            clear_area(
                grid,
                (
                    pos_dec(upper_left, (0, 1)),
                    set_x(bottom_right, get_x(upper_left) + mid),
                ),
            );
            clear_area(
                grid,
                (
                    (
                        get_x(bottom_right).saturating_sub(mid),
                        get_y(upper_left) - 1,
                    ),
                    bottom_right,
                ),
            );
        }

        /* Regardless of view mode, do the following */
        self.form.draw(grid, header_area, context);
        if let Some(ref mut embed_pty) = self.embed {
            let embed_area = (upper_left!(header_area), bottom_right!(body_area));
            match embed_pty {
                EmbedStatus::Running(_, _) => {
                    let mut guard = embed_pty.lock().unwrap();
                    clear_area(grid, embed_area);
                    copy_area(
                        grid,
                        &guard.grid,
                        embed_area,
                        ((0, 0), pos_dec(guard.terminal_size, (1, 1))),
                    );
                    guard.set_terminal_size((width!(embed_area), height!(embed_area)));
                    context.dirty_areas.push_back(area);
                    self.dirty = false;
                    return;
                }
                EmbedStatus::Stopped(_, _) => {
                    clear_area(grid, body_area);
                    write_string_to_grid(
                        "process has stopped, press 'e' to re-activate",
                        grid,
                        Color::Default,
                        Color::Default,
                        Attr::Default,
                        body_area,
                        None,
                    );
                    context.dirty_areas.push_back(area);
                }
            }
        } else {
            self.embed_area = (upper_left!(header_area), bottom_right!(body_area));
            self.pager.set_dirty(true);
            self.pager.draw(grid, body_area, context);
        }

        if self.cursor == Cursor::Body {
            change_colors(
                grid,
                (
                    set_y(upper_left!(body_area), get_y(bottom_right!(body_area))),
                    bottom_right!(body_area),
                ),
                Color::Default,
                Color::Byte(237),
            );
        } else {
            change_colors(
                grid,
                (
                    set_y(upper_left!(body_area), get_y(bottom_right!(body_area))),
                    bottom_right!(body_area),
                ),
                Color::Default,
                Color::Default,
            );
        }

        match self.mode {
            ViewMode::Edit | ViewMode::Embed => {}
            ViewMode::Send(ref mut s) => {
                s.draw(grid, center_area(area, s.content.size()), context);
            }
            ViewMode::SelectRecipients(ref mut s) => {
                s.draw(grid, center_area(area, s.content.size()), context);
            }
            ViewMode::Discard(_, ref mut s) => {
                /* Let user choose whether to quit with/without saving or cancel */
                s.draw(grid, center_area(area, s.content.size()), context);
            }
        }
        self.dirty = false;
        self.draw_attachments(grid, attachment_area, context);
        context.dirty_areas.push_back(area);
    }

    fn process_event(&mut self, event: &mut UIEvent, context: &mut Context) -> bool {
        let shortcuts = self.get_shortcuts(context);
        match (&mut self.mode, &event) {
            (ViewMode::Edit, _) => {
                if self.pager.process_event(event, context) {
                    return true;
                }
            }
            (ViewMode::Send(ref mut selector), _) => {
                if selector.process_event(event, context) {
                    if selector.is_done() {
                        let s = match std::mem::replace(&mut self.mode, ViewMode::Edit) {
                            ViewMode::Send(s) => s,
                            _ => unreachable!(),
                        };
                        let result: bool = s.collect().get(0).map(|b| *b).unwrap_or(false);
                        if result {
                            self.update_draft();
                            if send_draft(
                                self.sign_mail,
                                context,
                                self.account_cursor,
                                self.draft.clone(),
                                SpecialUsageMailbox::Sent,
                                Flag::SEEN,
                            ) {
                                context
                                    .replies
                                    .push_back(UIEvent::Action(Tab(Kill(self.id))));
                            } else {
                                save_draft(
                                    self.draft.clone().finalise().unwrap().as_bytes(),
                                    context,
                                    SpecialUsageMailbox::Drafts,
                                    Flag::SEEN | Flag::DRAFT,
                                    self.account_cursor,
                                );
                            }
                        }
                    }
                    return true;
                }
            }
            (ViewMode::SelectRecipients(ref mut selector), _) => {
                if selector.process_event(event, context) {
                    if selector.is_done() {
                        let s = match std::mem::replace(&mut self.mode, ViewMode::Edit) {
                            ViewMode::SelectRecipients(s) => s,
                            _ => unreachable!(),
                        };
                        let new_recipients = s.collect();
                        self.draft.headers_mut().insert(
                            "To".to_string(),
                            new_recipients
                                .into_iter()
                                .map(|a| a.to_string())
                                .collect::<Vec<String>>()
                                .join(", "),
                        );
                        self.update_form();
                    }
                    return true;
                }
            }
            (ViewMode::Discard(_, ref mut selector), _) => {
                if selector.process_event(event, context) {
                    if selector.is_done() {
                        let (u, s) = match std::mem::replace(&mut self.mode, ViewMode::Edit) {
                            ViewMode::Discard(u, s) => (u, s),
                            _ => unreachable!(),
                        };
                        let key = s.collect()[0] as char;
                        match key {
                            'x' => {
                                context.replies.push_back(UIEvent::Action(Tab(Kill(u))));
                                return true;
                            }
                            'n' => {}
                            'y' => {
                                save_draft(
                                    self.draft.clone().finalise().unwrap().as_bytes(),
                                    context,
                                    SpecialUsageMailbox::Drafts,
                                    Flag::SEEN | Flag::DRAFT,
                                    self.account_cursor,
                                );
                                context.replies.push_back(UIEvent::Action(Tab(Kill(u))));
                                return true;
                            }
                            _ => {}
                        }
                        self.set_dirty(true);
                    }
                    return true;
                }
            }
            _ => {}
        }
        if self.cursor == Cursor::Headers
            && self.mode.is_edit()
            && self.form.process_event(event, context)
        {
            if let UIEvent::InsertInput(_) = event {
                self.has_changes = true;
            }
            return true;
        }

        match *event {
            UIEvent::Resize => {
                self.set_dirty(true);
            }
            /*
            /* Switch e-mail From: field to the `left` configured account. */
            UIEvent::Input(Key::Left) if self.cursor == Cursor::From => {
            self.account_cursor = self.account_cursor.saturating_sub(1);
            self.draft.headers_mut().insert(
            "From".into(),
            get_display_name(context, self.account_cursor),
            );
            self.dirty = true;
            return true;
            }
            /* Switch e-mail From: field to the `right` configured account. */
            UIEvent::Input(Key::Right) if self.cursor == Cursor::From => {
            if self.account_cursor + 1 < context.accounts.len() {
            self.account_cursor += 1;
            self.draft.headers_mut().insert(
            "From".into(),
            get_display_name(context, self.account_cursor),
            );
            self.dirty = true;
            }
            return true;
            }*/
            UIEvent::Input(ref key)
                if shortcut!(key == shortcuts[Self::DESCRIPTION]["scroll_up"]) =>
            {
                self.cursor = Cursor::Headers;
                self.form.process_event(event, context);
                self.dirty = true;
            }
            UIEvent::Input(ref key)
                if shortcut!(key == shortcuts[Self::DESCRIPTION]["scroll_down"]) =>
            {
                self.cursor = Cursor::Body;
                self.dirty = true;
            }
            UIEvent::Input(ref key)
                if shortcut!(key == shortcuts[Self::DESCRIPTION]["send_mail"])
                    && self.mode.is_edit() =>
            {
                self.update_draft();
                self.mode = ViewMode::Send(Selector::new(
                    "send mail?",
                    vec![(true, "yes".to_string()), (false, "no".to_string())],
                    /* only one choice */
                    true,
                    context,
                ));
                return true;
            }
            UIEvent::EmbedInput((Key::Ctrl('z'), _)) => {
                self.embed.as_ref().unwrap().lock().unwrap().stop();
                match self.embed.take() {
                    Some(EmbedStatus::Running(e, f)) | Some(EmbedStatus::Stopped(e, f)) => {
                        self.embed = Some(EmbedStatus::Stopped(e, f));
                    }
                    _ => {}
                }
                context
                    .replies
                    .push_back(UIEvent::ChangeMode(UIMode::Normal));
                self.dirty = true;
            }
            UIEvent::EmbedInput((ref k, ref b)) => {
                use std::io::Write;
                if let Some(ref mut embed) = self.embed {
                    let mut embed_guard = embed.lock().unwrap();
                    if embed_guard.stdin.write_all(b).is_err() {
                        match embed_guard.is_active() {
                            Ok(WaitStatus::Exited(_, exit_code)) => {
                                drop(embed_guard);
                                if exit_code != 0 {
                                    context.replies.push_back(UIEvent::Notification(
                                        None,
                                        format!(
                                            "Subprocess has exited with exit code {}",
                                            exit_code
                                        ),
                                        Some(NotificationType::ERROR),
                                    ));
                                } else if let EmbedStatus::Running(_, f) = embed {
                                    let result = f.read_to_string();
                                    match Draft::from_str(result.as_str()) {
                                        Ok(mut new_draft) => {
                                            std::mem::swap(
                                                self.draft.attachments_mut(),
                                                new_draft.attachments_mut(),
                                            );
                                            if self.draft != new_draft {
                                                self.has_changes = true;
                                            }
                                            self.draft = new_draft;
                                        }
                                        Err(_) => {
                                            context.replies.push_back(UIEvent::Notification(
                                                    None,
                                                    "Could not parse draft headers correctly. The invalid text has been set as the body of your draft".to_string(),
                                                    Some(NotificationType::ERROR),
                                                    ));
                                            self.draft.set_body(result);
                                            self.has_changes = true;
                                        }
                                    }
                                    self.initialized = false;
                                }
                                self.embed = None;
                                self.mode = ViewMode::Edit;
                                context
                                    .replies
                                    .push_back(UIEvent::ChangeMode(UIMode::Normal));
                            }
                            Ok(WaitStatus::Stopped(_, _)) => {
                                drop(embed_guard);
                                match self.embed.take() {
                                    Some(EmbedStatus::Running(e, f))
                                    | Some(EmbedStatus::Stopped(e, f)) => {
                                        self.embed = Some(EmbedStatus::Stopped(e, f));
                                    }
                                    _ => {}
                                }
                                self.mode = ViewMode::Edit;
                                context
                                    .replies
                                    .push_back(UIEvent::ChangeMode(UIMode::Normal));
                                self.dirty = true;
                                return true;
                            }
                            Ok(WaitStatus::Continued(_)) | Ok(WaitStatus::StillAlive) => {
                                context
                                    .replies
                                    .push_back(UIEvent::EmbedInput((k.clone(), b.to_vec())));
                                return true;
                            }
                            e => {
                                context.replies.push_back(UIEvent::Notification(
                                    None,
                                    format!("Subprocess has exited with reason {:?}", e),
                                    Some(NotificationType::ERROR),
                                ));
                                drop(embed_guard);
                                self.embed = None;
                                self.mode = ViewMode::Edit;
                                context
                                    .replies
                                    .push_back(UIEvent::ChangeMode(UIMode::Normal));
                            }
                        }
                    }
                }
                self.set_dirty(true);
                return true;
            }
            UIEvent::Input(ref key)
                if self.embed.is_some()
                    && shortcut!(key == shortcuts[Self::DESCRIPTION]["edit_mail"]) =>
            {
                self.embed.as_ref().unwrap().lock().unwrap().wake_up();
                match self.embed.take() {
                    Some(EmbedStatus::Running(e, f)) | Some(EmbedStatus::Stopped(e, f)) => {
                        self.embed = Some(EmbedStatus::Running(e, f));
                    }
                    _ => {}
                }
                self.mode = ViewMode::Embed;
                context
                    .replies
                    .push_back(UIEvent::ChangeMode(UIMode::Embed));
                self.set_dirty(true);
                return true;
            }
            UIEvent::Input(ref key)
                if self.mode.is_edit()
                    && shortcut!(key == shortcuts[Self::DESCRIPTION]["edit_mail"]) =>
            {
                /* Edit draft in $EDITOR */
                let settings = &context.settings;
                let editor = if let Some(editor_cmd) = settings.composing.editor_cmd.as_ref() {
                    editor_cmd.to_string()
                } else {
                    match std::env::var("EDITOR") {
                        Err(e) => {
                            context.replies.push_back(UIEvent::Notification(
                            Some(e.to_string()),
                            "$EDITOR is not set. You can change an envvar's value with setenv or set composing.editor_cmd setting in your configuration.".to_string(),
                            Some(NotificationType::ERROR),
                        ));
                            return true;
                        }
                        Ok(v) => v,
                    }
                };
                /* update Draft's headers based on form values */
                self.update_draft();
                let f = create_temp_file(
                    self.draft.to_string().unwrap().as_str().as_bytes(),
                    None,
                    None,
                    true,
                );

                if settings.composing.embed {
                    self.embed = Some(EmbedStatus::Running(
                        crate::terminal::embed::create_pty(
                            width!(self.embed_area),
                            height!(self.embed_area),
                            [editor, f.path().display().to_string()].join(" "),
                        )
                        .unwrap(),
                        f,
                    ));
                    self.dirty = true;
                    context
                        .replies
                        .push_back(UIEvent::ChangeMode(UIMode::Embed));
                    context.replies.push_back(UIEvent::Fork(ForkType::Embed(
                        self.embed.as_ref().unwrap().lock().unwrap().child_pid,
                    )));
                    self.mode = ViewMode::Embed;
                    return true;
                }
                use std::process::{Command, Stdio};
                /* Kill input thread so that spawned command can be sole receiver of stdin */
                {
                    context.input_kill();
                }

                let parts = split_command!(editor);
                let (cmd, args) = (parts[0], &parts[1..]);
                if let Err(e) = Command::new(cmd)
                    .args(args)
                    .arg(&f.path())
                    .stdin(Stdio::inherit())
                    .stdout(Stdio::inherit())
                    .output()
                {
                    context.replies.push_back(UIEvent::Notification(
                        Some(format!("Failed to execute {}", editor)),
                        e.to_string(),
                        Some(NotificationType::ERROR),
                    ));
                    context.replies.push_back(UIEvent::Fork(ForkType::Finished));
                    context.restore_input();
                    return true;
                }
                context.replies.push_back(UIEvent::Fork(ForkType::Finished));
                let result = f.read_to_string();
                match Draft::from_str(result.as_str()) {
                    Ok(mut new_draft) => {
                        std::mem::swap(self.draft.attachments_mut(), new_draft.attachments_mut());
                        if self.draft != new_draft {
                            self.has_changes = true;
                        }
                        self.draft = new_draft;
                    }
                    Err(_) => {
                        context.replies.push_back(UIEvent::Notification(
                                                    None,
                                                    "Could not parse draft headers correctly. The invalid text has been set as the body of your draft".to_string(),
                                                    Some(NotificationType::ERROR),
                                                    ));
                        self.draft.set_body(result);
                        self.has_changes = true;
                    }
                }
                self.initialized = false;
                context.restore_input();
                self.dirty = true;
                return true;
            }
            UIEvent::Action(ref a) => {
                match a {
                    Action::Compose(ComposeAction::AddAttachment(ref path)) => {
                        let mut attachment = match melib::email::attachment_from_file(path) {
                            Ok(a) => a,
                            Err(e) => {
                                context.replies.push_back(UIEvent::Notification(
                                    Some("could not add attachment".to_string()),
                                    e.to_string(),
                                    Some(NotificationType::ERROR),
                                ));
                                self.dirty = true;
                                return true;
                            }
                        };
                        if let Ok(mime_type) = query_mime_info(path) {
                            match attachment.content_type {
                                ContentType::Other { ref mut tag, .. } => {
                                    *tag = mime_type;
                                }
                                _ => {}
                            }
                        }
                        self.draft.attachments_mut().push(attachment);
                        self.dirty = true;
                        return true;
                    }
                    Action::Compose(ComposeAction::RemoveAttachment(idx)) => {
                        if *idx + 1 > self.draft.attachments().len() {
                            context.replies.push_back(UIEvent::StatusEvent(
                                StatusEvent::DisplayMessage(
                                    "attachment with given index does not exist".to_string(),
                                ),
                            ));
                            self.dirty = true;
                            return true;
                        }
                        self.draft.attachments_mut().remove(*idx);
                        context.replies.push_back(UIEvent::StatusEvent(
                            StatusEvent::DisplayMessage("attachment removed".to_string()),
                        ));
                        self.dirty = true;
                        return true;
                    }
                    Action::Compose(ComposeAction::ToggleSign) => {
                        let is_true = self.sign_mail.is_true();
                        self.sign_mail = ToggleFlag::from(!is_true);
                        self.dirty = true;
                        return true;
                    }
                    _ => {}
                }
            }
            _ => {}
        }
        false
    }

    fn is_dirty(&self) -> bool {
        match self.mode {
            ViewMode::Embed => true,
            _ => self.dirty || self.pager.is_dirty() || self.form.is_dirty(),
        }
    }

    fn set_dirty(&mut self, value: bool) {
        self.dirty = value;
        self.pager.set_dirty(value);
        self.form.set_dirty(value);
    }

    fn kill(&mut self, uuid: Uuid, context: &mut Context) {
        if !self.has_changes {
            context.replies.push_back(UIEvent::Action(Tab(Kill(uuid))));
            return;
        }

        self.mode = ViewMode::Discard(
            uuid,
            Selector::new(
                "this draft has unsaved changes",
                vec![
                    ('x', "quit without saving".to_string()),
                    ('y', "save draft and quit".to_string()),
                    ('n', "cancel".to_string()),
                ],
                true,
                context,
            ),
        );
    }

    fn get_shortcuts(&self, context: &Context) -> ShortcutMaps {
        let mut map = if self.mode.is_edit() {
            self.pager.get_shortcuts(context)
        } else {
            Default::default()
        };

        let our_map: ShortcutMap = context.settings.shortcuts.composing.key_values();
        map.insert(Composer::DESCRIPTION, our_map);

        map
    }

    fn id(&self) -> ComponentId {
        self.id
    }
    fn set_id(&mut self, id: ComponentId) {
        self.id = id;
    }

    fn can_quit_cleanly(&mut self, context: &Context) -> bool {
        if !self.has_changes {
            return true;
        }

        /* Play it safe and ask user for confirmation */
        self.mode = ViewMode::Discard(
            self.id,
            Selector::new(
                "this draft has unsaved changes",
                vec![
                    ('x', "quit without saving".to_string()),
                    ('y', "save draft and quit".to_string()),
                    ('n', "cancel".to_string()),
                ],
                true,
                context,
            ),
        );
        self.set_dirty(true);
        false
    }
}

pub fn send_draft(
    sign_mail: ToggleFlag,
    context: &mut Context,
    account_cursor: usize,
    mut draft: Draft,
    folder_type: SpecialUsageMailbox,
    flags: Flag,
) -> bool {
    use std::io::Write;
    use std::process::{Command, Stdio};
    let settings = &context.settings;
    let format_flowed = settings.composing.format_flowed;
    let parts = split_command!(settings.composing.mailer_cmd);
    if parts.is_empty() {
        context.replies.push_back(UIEvent::Notification(
            None,
            String::from("mailer_cmd configuration value is empty"),
            Some(NotificationType::ERROR),
        ));
        return false;
    }
    let bytes;
    let (cmd, args) = (parts[0], &parts[1..]);
    let mut msmtp = Command::new(cmd)
        .args(args)
        .stdin(Stdio::piped())
        .stdout(Stdio::piped())
        .spawn()
        .expect("Failed to start mailer command");
    {
        let stdin = msmtp.stdin.as_mut().expect("failed to open stdin");
        if sign_mail.is_true() {
            let mut content_type = ContentType::default();
            if format_flowed {
                if let ContentType::Text {
                    ref mut parameters, ..
                } = content_type
                {
                    parameters.push((b"format".to_vec(), b"flowed".to_vec()));
                }
            }

            let mut body: AttachmentBuilder = Attachment::new(
                content_type,
                Default::default(),
                std::mem::replace(&mut draft.body, String::new()).into_bytes(),
            )
            .into();
            if !draft.attachments.is_empty() {
                let mut parts = std::mem::replace(&mut draft.attachments, Vec::new());
                parts.insert(0, body);
                let boundary = ContentType::make_boundary(&parts);
                body = Attachment::new(
                    ContentType::Multipart {
                        boundary: boundary.into_bytes(),
                        kind: MultipartType::Mixed,
                        parts: parts.into_iter().map(|a| a.into()).collect::<Vec<_>>(),
                    },
                    Default::default(),
                    Vec::new(),
                )
                .into();
            }
            let output = crate::components::mail::pgp::sign(
                body.into(),
                context.settings.pgp.gpg_binary.as_ref().map(String::as_str),
                context.settings.pgp.key.as_ref().map(String::as_str),
            );
            if let Err(e) = &output {
                debug!("{:?} could not sign draft msg", e);
                log(
                    format!(
                        "Could not sign draft in account `{}`: {}.",
                        context.accounts[account_cursor].name(),
                        e.to_string()
                    ),
                    ERROR,
                );
                context.replies.push_back(UIEvent::Notification(
                    Some(format!(
                        "Could not sign draft in account `{}`.",
                        context.accounts[account_cursor].name()
                    )),
                    e.to_string(),
                    Some(NotificationType::ERROR),
                ));
                return false;
            }
            draft.attachments.push(output.unwrap());
        } else {
            let mut content_type = ContentType::default();
            if format_flowed {
                if let ContentType::Text {
                    ref mut parameters, ..
                } = content_type
                {
                    parameters.push((b"format".to_vec(), b"flowed".to_vec()));
                }

                let body: AttachmentBuilder = Attachment::new(
                    content_type,
                    Default::default(),
                    std::mem::replace(&mut draft.body, String::new()).into_bytes(),
                )
                .into();
                draft.attachments.insert(0, body);
            }
        }
        bytes = draft.finalise().unwrap();
        stdin
            .write_all(bytes.as_bytes())
            .expect("Failed to write to stdin");
    }
    let output = msmtp.wait().expect("Failed to wait on mailer");
    if output.success() {
        context.replies.push_back(UIEvent::Notification(
            Some("Sent.".into()),
            String::new(),
            None,
        ));
    } else {
        let error_message = if let Some(exit_code) = output.code() {
            format!(
                "Could not send e-mail using `{}`: Process exited with {}",
                cmd, exit_code
            )
        } else {
            format!(
                "Could not send e-mail using `{}`: Process was killed by signal",
                cmd
            )
        };
        context.replies.push_back(UIEvent::Notification(
            Some("Message not sent.".into()),
            error_message.clone(),
            Some(NotificationType::ERROR),
        ));
        log(error_message, ERROR);
    }
    save_draft(
        bytes.as_bytes(),
        context,
        folder_type,
        flags,
        account_cursor,
    );
    true
}

pub fn save_draft(
    bytes: &[u8],
    context: &mut Context,
    folder_type: SpecialUsageMailbox,
    flags: Flag,
    account_cursor: usize,
) {
    if let Err(MeliError { summary, details }) =
        context.accounts[account_cursor].save_special(bytes, folder_type, flags)
    {
        context.replies.push_back(UIEvent::Notification(
            summary.map(|s| s.into()),
            details.into(),
            Some(NotificationType::ERROR),
        ));
    }
}