mod persistence;
pub mod terminal_element;

use std::{
    ops::RangeInclusive,
    path::{Path, PathBuf},
    time::Duration,
};

use context_menu::{ContextMenu, ContextMenuItem};
use dirs::home_dir;
use gpui::{
    actions,
    elements::{AnchorCorner, ChildView, Flex, Label, ParentElement, Stack, Text},
    geometry::vector::Vector2F,
    impl_actions, impl_internal_actions,
    keymap_matcher::{KeymapContext, Keystroke},
    AnyViewHandle, AppContext, Element, ElementBox, Entity, ModelHandle, MutableAppContext, Task,
    View, ViewContext, ViewHandle, WeakViewHandle,
};
use project::{LocalWorktree, Project};
use serde::Deserialize;
use settings::{Settings, TerminalBlink, WorkingDirectory};
use smol::Timer;
use terminal::{
    alacritty_terminal::{
        index::Point,
        term::{search::RegexSearch, TermMode},
    },
    Event, Terminal,
};
use util::{truncate_and_trailoff, ResultExt};
use workspace::{
    item::{Item, ItemEvent},
    notifications::NotifyResultExt,
    pane, register_deserializable_item,
    searchable::{SearchEvent, SearchOptions, SearchableItem, SearchableItemHandle},
    Pane, ToolbarItemLocation, Workspace, WorkspaceId,
};

use crate::{persistence::TERMINAL_DB, terminal_element::TerminalElement};

const CURSOR_BLINK_INTERVAL: Duration = Duration::from_millis(500);

///Event to transmit the scroll from the element to the view
#[derive(Clone, Debug, PartialEq)]
pub struct ScrollTerminal(pub i32);

#[derive(Clone, PartialEq)]
pub struct DeployContextMenu {
    pub position: Vector2F,
}

#[derive(Clone, Default, Deserialize, PartialEq)]
pub struct SendText(String);

#[derive(Clone, Default, Deserialize, PartialEq)]
pub struct SendKeystroke(String);

actions!(
    terminal,
    [Clear, Copy, Paste, ShowCharacterPalette, SearchTest]
);

impl_actions!(terminal, [SendText, SendKeystroke]);

impl_internal_actions!(project_panel, [DeployContextMenu]);

pub fn init(cx: &mut MutableAppContext) {
    cx.add_action(TerminalView::deploy);

    register_deserializable_item::<TerminalView>(cx);

    //Useful terminal views
    cx.add_action(TerminalView::send_text);
    cx.add_action(TerminalView::send_keystroke);
    cx.add_action(TerminalView::deploy_context_menu);
    cx.add_action(TerminalView::copy);
    cx.add_action(TerminalView::paste);
    cx.add_action(TerminalView::clear);
    cx.add_action(TerminalView::show_character_palette);
}

///A terminal view, maintains the PTY's file handles and communicates with the terminal
pub struct TerminalView {
    terminal: ModelHandle<Terminal>,
    has_new_content: bool,
    //Currently using iTerm bell, show bell emoji in tab until input is received
    has_bell: bool,
    context_menu: ViewHandle<ContextMenu>,
    blink_state: bool,
    blinking_on: bool,
    blinking_paused: bool,
    blink_epoch: usize,
    workspace_id: WorkspaceId,
}

impl Entity for TerminalView {
    type Event = Event;
}

impl TerminalView {
    ///Create a new Terminal in the current working directory or the user's home directory
    pub fn deploy(
        workspace: &mut Workspace,
        _: &workspace::NewTerminal,
        cx: &mut ViewContext<Workspace>,
    ) {
        let strategy = cx.global::<Settings>().terminal_strategy();

        let working_directory = get_working_directory(workspace, cx, strategy);

        let window_id = cx.window_id();
        let terminal = workspace
            .project()
            .update(cx, |project, cx| {
                project.create_terminal(working_directory, window_id, cx)
            })
            .notify_err(workspace, cx);

        if let Some(terminal) = terminal {
            let view = cx.add_view(|cx| TerminalView::new(terminal, workspace.database_id(), cx));
            workspace.add_item(Box::new(view), cx)
        }
    }

    pub fn new(
        terminal: ModelHandle<Terminal>,
        workspace_id: WorkspaceId,
        cx: &mut ViewContext<Self>,
    ) -> Self {
        cx.observe(&terminal, |_, _, cx| cx.notify()).detach();
        cx.subscribe(&terminal, |this, _, event, cx| match event {
            Event::Wakeup => {
                if !cx.is_self_focused() {
                    this.has_new_content = true;
                    cx.notify();
                }
                cx.emit(Event::Wakeup);
            }
            Event::Bell => {
                this.has_bell = true;
                cx.emit(Event::Wakeup);
            }
            Event::BlinkChanged => this.blinking_on = !this.blinking_on,
            Event::TitleChanged => {
                if let Some(foreground_info) = &this.terminal().read(cx).foreground_process_info {
                    let cwd = foreground_info.cwd.clone();

                    let item_id = cx.view_id();
                    let workspace_id = this.workspace_id;
                    cx.background()
                        .spawn(async move {
                            TERMINAL_DB
                                .save_working_directory(item_id, workspace_id, cwd)
                                .await
                                .log_err();
                        })
                        .detach();
                }
            }
            _ => cx.emit(*event),
        })
        .detach();

        Self {
            terminal,
            has_new_content: true,
            has_bell: false,
            context_menu: cx.add_view(ContextMenu::new),
            blink_state: true,
            blinking_on: false,
            blinking_paused: false,
            blink_epoch: 0,
            workspace_id,
        }
    }

    pub fn handle(&self) -> ModelHandle<Terminal> {
        self.terminal.clone()
    }

    pub fn has_new_content(&self) -> bool {
        self.has_new_content
    }

    pub fn has_bell(&self) -> bool {
        self.has_bell
    }

    pub fn clear_bel(&mut self, cx: &mut ViewContext<TerminalView>) {
        self.has_bell = false;
        cx.emit(Event::Wakeup);
    }

    pub fn deploy_context_menu(&mut self, action: &DeployContextMenu, cx: &mut ViewContext<Self>) {
        let menu_entries = vec![
            ContextMenuItem::item("Clear", Clear),
            ContextMenuItem::item("Close", pane::CloseActiveItem),
        ];

        self.context_menu.update(cx, |menu, cx| {
            menu.show(action.position, AnchorCorner::TopLeft, menu_entries, cx)
        });

        cx.notify();
    }

    fn show_character_palette(&mut self, _: &ShowCharacterPalette, cx: &mut ViewContext<Self>) {
        if !self
            .terminal
            .read(cx)
            .last_content
            .mode
            .contains(TermMode::ALT_SCREEN)
        {
            cx.show_character_palette();
        } else {
            self.terminal.update(cx, |term, cx| {
                term.try_keystroke(
                    &Keystroke::parse("ctrl-cmd-space").unwrap(),
                    cx.global::<Settings>()
                        .terminal_overrides
                        .option_as_meta
                        .unwrap_or(false),
                )
            });
        }
    }

    fn clear(&mut self, _: &Clear, cx: &mut ViewContext<Self>) {
        self.terminal.update(cx, |term, _| term.clear());
        cx.notify();
    }

    pub fn should_show_cursor(
        &self,
        focused: bool,
        cx: &mut gpui::RenderContext<'_, Self>,
    ) -> bool {
        //Don't blink the cursor when not focused, blinking is disabled, or paused
        if !focused
            || !self.blinking_on
            || self.blinking_paused
            || self
                .terminal
                .read(cx)
                .last_content
                .mode
                .contains(TermMode::ALT_SCREEN)
        {
            return true;
        }

        let setting = {
            let settings = cx.global::<Settings>();
            settings
                .terminal_overrides
                .blinking
                .clone()
                .unwrap_or(TerminalBlink::TerminalControlled)
        };

        match setting {
            //If the user requested to never blink, don't blink it.
            TerminalBlink::Off => true,
            //If the terminal is controlling it, check terminal mode
            TerminalBlink::TerminalControlled | TerminalBlink::On => self.blink_state,
        }
    }

    fn blink_cursors(&mut self, epoch: usize, cx: &mut ViewContext<Self>) {
        if epoch == self.blink_epoch && !self.blinking_paused {
            self.blink_state = !self.blink_state;
            cx.notify();

            let epoch = self.next_blink_epoch();
            cx.spawn(|this, mut cx| {
                let this = this.downgrade();
                async move {
                    Timer::after(CURSOR_BLINK_INTERVAL).await;
                    if let Some(this) = this.upgrade(&cx) {
                        this.update(&mut cx, |this, cx| this.blink_cursors(epoch, cx));
                    }
                }
            })
            .detach();
        }
    }

    pub fn pause_cursor_blinking(&mut self, cx: &mut ViewContext<Self>) {
        self.blink_state = true;
        cx.notify();

        let epoch = self.next_blink_epoch();
        cx.spawn(|this, mut cx| {
            let this = this.downgrade();
            async move {
                Timer::after(CURSOR_BLINK_INTERVAL).await;
                if let Some(this) = this.upgrade(&cx) {
                    this.update(&mut cx, |this, cx| this.resume_cursor_blinking(epoch, cx))
                }
            }
        })
        .detach();
    }

    pub fn find_matches(
        &mut self,
        query: project::search::SearchQuery,
        cx: &mut ViewContext<Self>,
    ) -> Task<Vec<RangeInclusive<Point>>> {
        let searcher = regex_search_for_query(query);

        if let Some(searcher) = searcher {
            self.terminal
                .update(cx, |term, cx| term.find_matches(searcher, cx))
        } else {
            cx.background().spawn(async { Vec::new() })
        }
    }

    pub fn terminal(&self) -> &ModelHandle<Terminal> {
        &self.terminal
    }

    fn next_blink_epoch(&mut self) -> usize {
        self.blink_epoch += 1;
        self.blink_epoch
    }

    fn resume_cursor_blinking(&mut self, epoch: usize, cx: &mut ViewContext<Self>) {
        if epoch == self.blink_epoch {
            self.blinking_paused = false;
            self.blink_cursors(epoch, cx);
        }
    }

    ///Attempt to paste the clipboard into the terminal
    fn copy(&mut self, _: &Copy, cx: &mut ViewContext<Self>) {
        self.terminal.update(cx, |term, _| term.copy())
    }

    ///Attempt to paste the clipboard into the terminal
    fn paste(&mut self, _: &Paste, cx: &mut ViewContext<Self>) {
        if let Some(item) = cx.read_from_clipboard() {
            self.terminal
                .update(cx, |terminal, _cx| terminal.paste(item.text()));
        }
    }

    fn send_text(&mut self, text: &SendText, cx: &mut ViewContext<Self>) {
        self.clear_bel(cx);
        self.terminal.update(cx, |term, _| {
            term.input(text.0.to_string());
        });
    }

    fn send_keystroke(&mut self, text: &SendKeystroke, cx: &mut ViewContext<Self>) {
        if let Some(keystroke) = Keystroke::parse(&text.0).log_err() {
            self.clear_bel(cx);
            self.terminal.update(cx, |term, cx| {
                term.try_keystroke(
                    &keystroke,
                    cx.global::<Settings>()
                        .terminal_overrides
                        .option_as_meta
                        .unwrap_or(false),
                );
            });
        }
    }
}

pub fn regex_search_for_query(query: project::search::SearchQuery) -> Option<RegexSearch> {
    let searcher = match query {
        project::search::SearchQuery::Text { query, .. } => RegexSearch::new(&query),
        project::search::SearchQuery::Regex { query, .. } => RegexSearch::new(&query),
    };
    searcher.ok()
}

impl View for TerminalView {
    fn ui_name() -> &'static str {
        "Terminal"
    }

    fn render(&mut self, cx: &mut gpui::RenderContext<'_, Self>) -> ElementBox {
        let terminal_handle = self.terminal.clone().downgrade();

        let self_id = cx.view_id();
        let focused = cx
            .focused_view_id(cx.window_id())
            .filter(|view_id| *view_id == self_id)
            .is_some();

        Stack::new()
            .with_child(
                TerminalElement::new(
                    cx.handle(),
                    terminal_handle,
                    focused,
                    self.should_show_cursor(focused, cx),
                )
                .contained()
                .boxed(),
            )
            .with_child(ChildView::new(&self.context_menu, cx).boxed())
            .boxed()
    }

    fn focus_in(&mut self, _: AnyViewHandle, cx: &mut ViewContext<Self>) {
        self.has_new_content = false;
        self.terminal.read(cx).focus_in();
        self.blink_cursors(self.blink_epoch, cx);
        cx.notify();
    }

    fn focus_out(&mut self, _: AnyViewHandle, cx: &mut ViewContext<Self>) {
        self.terminal.update(cx, |terminal, _| {
            terminal.focus_out();
        });
        cx.notify();
    }

    fn key_down(&mut self, event: &gpui::KeyDownEvent, cx: &mut ViewContext<Self>) -> bool {
        self.clear_bel(cx);
        self.pause_cursor_blinking(cx);

        self.terminal.update(cx, |term, cx| {
            term.try_keystroke(
                &event.keystroke,
                cx.global::<Settings>()
                    .terminal_overrides
                    .option_as_meta
                    .unwrap_or(false),
            )
        })
    }

    //IME stuff
    fn selected_text_range(&self, cx: &AppContext) -> Option<std::ops::Range<usize>> {
        if self
            .terminal
            .read(cx)
            .last_content
            .mode
            .contains(TermMode::ALT_SCREEN)
        {
            None
        } else {
            Some(0..0)
        }
    }

    fn replace_text_in_range(
        &mut self,
        _: Option<std::ops::Range<usize>>,
        text: &str,
        cx: &mut ViewContext<Self>,
    ) {
        self.terminal.update(cx, |terminal, _| {
            terminal.input(text.into());
        });
    }

    fn keymap_context(&self, cx: &gpui::AppContext) -> KeymapContext {
        let mut context = Self::default_keymap_context();

        let mode = self.terminal.read(cx).last_content.mode;
        context.map.insert(
            "screen".to_string(),
            (if mode.contains(TermMode::ALT_SCREEN) {
                "alt"
            } else {
                "normal"
            })
            .to_string(),
        );

        if mode.contains(TermMode::APP_CURSOR) {
            context.set.insert("DECCKM".to_string());
        }
        if mode.contains(TermMode::APP_KEYPAD) {
            context.set.insert("DECPAM".to_string());
        }
        //Note the ! here
        if !mode.contains(TermMode::APP_KEYPAD) {
            context.set.insert("DECPNM".to_string());
        }
        if mode.contains(TermMode::SHOW_CURSOR) {
            context.set.insert("DECTCEM".to_string());
        }
        if mode.contains(TermMode::LINE_WRAP) {
            context.set.insert("DECAWM".to_string());
        }
        if mode.contains(TermMode::ORIGIN) {
            context.set.insert("DECOM".to_string());
        }
        if mode.contains(TermMode::INSERT) {
            context.set.insert("IRM".to_string());
        }
        //LNM is apparently the name for this. https://vt100.net/docs/vt510-rm/LNM.html
        if mode.contains(TermMode::LINE_FEED_NEW_LINE) {
            context.set.insert("LNM".to_string());
        }
        if mode.contains(TermMode::FOCUS_IN_OUT) {
            context.set.insert("report_focus".to_string());
        }
        if mode.contains(TermMode::ALTERNATE_SCROLL) {
            context.set.insert("alternate_scroll".to_string());
        }
        if mode.contains(TermMode::BRACKETED_PASTE) {
            context.set.insert("bracketed_paste".to_string());
        }
        if mode.intersects(TermMode::MOUSE_MODE) {
            context.set.insert("any_mouse_reporting".to_string());
        }
        {
            let mouse_reporting = if mode.contains(TermMode::MOUSE_REPORT_CLICK) {
                "click"
            } else if mode.contains(TermMode::MOUSE_DRAG) {
                "drag"
            } else if mode.contains(TermMode::MOUSE_MOTION) {
                "motion"
            } else {
                "off"
            };
            context
                .map
                .insert("mouse_reporting".to_string(), mouse_reporting.to_string());
        }
        {
            let format = if mode.contains(TermMode::SGR_MOUSE) {
                "sgr"
            } else if mode.contains(TermMode::UTF8_MOUSE) {
                "utf8"
            } else {
                "normal"
            };
            context
                .map
                .insert("mouse_format".to_string(), format.to_string());
        }
        context
    }
}

impl Item for TerminalView {
    fn tab_content(
        &self,
        _detail: Option<usize>,
        tab_theme: &theme::Tab,
        cx: &gpui::AppContext,
    ) -> ElementBox {
        let title = self
            .terminal()
            .read(cx)
            .foreground_process_info
            .as_ref()
            .map(|fpi| {
                format!(
                    "{} — {}",
                    truncate_and_trailoff(
                        &fpi.cwd
                            .file_name()
                            .map(|name| name.to_string_lossy().to_string())
                            .unwrap_or_default(),
                        25
                    ),
                    truncate_and_trailoff(
                        &{
                            format!(
                                "{}{}",
                                fpi.name,
                                if fpi.argv.len() >= 1 {
                                    format!(" {}", (&fpi.argv[1..]).join(" "))
                                } else {
                                    "".to_string()
                                }
                            )
                        },
                        25
                    )
                )
            })
            .unwrap_or_else(|| "Terminal".to_string());

        Flex::row()
            .with_child(
                Label::new(title, tab_theme.label.clone())
                    .aligned()
                    .contained()
                    .boxed(),
            )
            .boxed()
    }

    fn clone_on_split(
        &self,
        _workspace_id: WorkspaceId,
        _cx: &mut ViewContext<Self>,
    ) -> Option<Self> {
        //From what I can tell, there's no  way to tell the current working
        //Directory of the terminal from outside the shell. There might be
        //solutions to this, but they are non-trivial and require more IPC

        // Some(TerminalContainer::new(
        //     Err(anyhow::anyhow!("failed to instantiate terminal")),
        //     workspace_id,
        //     cx,
        // ))

        // TODO
        None
    }

    fn for_each_project_item(&self, _: &AppContext, _: &mut dyn FnMut(usize, &dyn project::Item)) {}

    fn is_singleton(&self, _cx: &gpui::AppContext) -> bool {
        false
    }

    fn set_nav_history(&mut self, _: workspace::ItemNavHistory, _: &mut ViewContext<Self>) {}

    fn can_save(&self, _cx: &gpui::AppContext) -> bool {
        false
    }

    fn save(
        &mut self,
        _project: gpui::ModelHandle<Project>,
        _cx: &mut ViewContext<Self>,
    ) -> gpui::Task<gpui::anyhow::Result<()>> {
        unreachable!("save should not have been called");
    }

    fn save_as(
        &mut self,
        _project: gpui::ModelHandle<Project>,
        _abs_path: std::path::PathBuf,
        _cx: &mut ViewContext<Self>,
    ) -> gpui::Task<gpui::anyhow::Result<()>> {
        unreachable!("save_as should not have been called");
    }

    fn reload(
        &mut self,
        _project: gpui::ModelHandle<Project>,
        _cx: &mut ViewContext<Self>,
    ) -> gpui::Task<gpui::anyhow::Result<()>> {
        gpui::Task::ready(Ok(()))
    }

    fn is_dirty(&self, _cx: &gpui::AppContext) -> bool {
        self.has_bell()
    }

    fn has_conflict(&self, _cx: &AppContext) -> bool {
        false
    }

    fn as_searchable(&self, handle: &ViewHandle<Self>) -> Option<Box<dyn SearchableItemHandle>> {
        Some(Box::new(handle.clone()))
    }

    fn to_item_events(event: &Self::Event) -> Vec<ItemEvent> {
        match event {
            Event::BreadcrumbsChanged => vec![ItemEvent::UpdateBreadcrumbs],
            Event::TitleChanged | Event::Wakeup => vec![ItemEvent::UpdateTab],
            Event::CloseTerminal => vec![ItemEvent::CloseItem],
            _ => vec![],
        }
    }

    fn breadcrumb_location(&self) -> ToolbarItemLocation {
        ToolbarItemLocation::PrimaryLeft { flex: None }
    }

    fn breadcrumbs(&self, theme: &theme::Theme, cx: &AppContext) -> Option<Vec<ElementBox>> {
        Some(vec![Text::new(
            self.terminal().read(cx).breadcrumb_text.to_string(),
            theme.breadcrumbs.text.clone(),
        )
        .boxed()])
    }

    fn serialized_item_kind() -> Option<&'static str> {
        Some("Terminal")
    }

    fn deserialize(
        project: ModelHandle<Project>,
        _workspace: WeakViewHandle<Workspace>,
        workspace_id: workspace::WorkspaceId,
        item_id: workspace::ItemId,
        cx: &mut ViewContext<Pane>,
    ) -> Task<anyhow::Result<ViewHandle<Self>>> {
        let window_id = cx.window_id();
        cx.spawn(|pane, mut cx| async move {
            let cwd = TERMINAL_DB
                .get_working_directory(item_id, workspace_id)
                .log_err()
                .flatten();

            cx.update(|cx| {
                let terminal = project.update(cx, |project, cx| {
                    project.create_terminal(cwd, window_id, cx)
                })?;

                Ok(cx.add_view(pane, |cx| TerminalView::new(terminal, workspace_id, cx)))
            })
        })
    }

    fn added_to_workspace(&mut self, workspace: &mut Workspace, cx: &mut ViewContext<Self>) {
        cx.background()
            .spawn(TERMINAL_DB.update_workspace_id(
                workspace.database_id(),
                self.workspace_id,
                cx.view_id(),
            ))
            .detach();
        self.workspace_id = workspace.database_id();
    }
}

impl SearchableItem for TerminalView {
    type Match = RangeInclusive<Point>;

    fn supported_options() -> SearchOptions {
        SearchOptions {
            case: false,
            word: false,
            regex: false,
        }
    }

    /// Convert events raised by this item into search-relevant events (if applicable)
    fn to_search_event(event: &Self::Event) -> Option<SearchEvent> {
        match event {
            Event::Wakeup => Some(SearchEvent::MatchesInvalidated),
            Event::SelectionsChanged => Some(SearchEvent::ActiveMatchChanged),
            _ => None,
        }
    }

    /// Clear stored matches
    fn clear_matches(&mut self, cx: &mut ViewContext<Self>) {
        self.terminal().update(cx, |term, _| term.matches.clear())
    }

    /// Store matches returned from find_matches somewhere for rendering
    fn update_matches(&mut self, matches: Vec<Self::Match>, cx: &mut ViewContext<Self>) {
        self.terminal().update(cx, |term, _| term.matches = matches)
    }

    /// Return the selection content to pre-load into this search
    fn query_suggestion(&mut self, cx: &mut ViewContext<Self>) -> String {
        self.terminal()
            .read(cx)
            .last_content
            .selection_text
            .clone()
            .unwrap_or_default()
    }

    /// Focus match at given index into the Vec of matches
    fn activate_match(&mut self, index: usize, _: Vec<Self::Match>, cx: &mut ViewContext<Self>) {
        self.terminal()
            .update(cx, |term, _| term.activate_match(index));
        cx.notify();
    }

    /// Get all of the matches for this query, should be done on the background
    fn find_matches(
        &mut self,
        query: project::search::SearchQuery,
        cx: &mut ViewContext<Self>,
    ) -> Task<Vec<Self::Match>> {
        if let Some(searcher) = regex_search_for_query(query) {
            self.terminal()
                .update(cx, |term, cx| term.find_matches(searcher, cx))
        } else {
            Task::ready(vec![])
        }
    }

    /// Reports back to the search toolbar what the active match should be (the selection)
    fn active_match_index(
        &mut self,
        matches: Vec<Self::Match>,
        cx: &mut ViewContext<Self>,
    ) -> Option<usize> {
        // Selection head might have a value if there's a selection that isn't
        // associated with a match. Therefore, if there are no matches, we should
        // report None, no matter the state of the terminal
        let res = if matches.len() > 0 {
            if let Some(selection_head) = self.terminal().read(cx).selection_head {
                // If selection head is contained in a match. Return that match
                if let Some(ix) = matches
                    .iter()
                    .enumerate()
                    .find(|(_, search_match)| {
                        search_match.contains(&selection_head)
                            || search_match.start() > &selection_head
                    })
                    .map(|(ix, _)| ix)
                {
                    Some(ix)
                } else {
                    // If no selection after selection head, return the last match
                    Some(matches.len().saturating_sub(1))
                }
            } else {
                // Matches found but no active selection, return the first last one (closest to cursor)
                Some(matches.len().saturating_sub(1))
            }
        } else {
            None
        };

        res
    }
}

///Get's the working directory for the given workspace, respecting the user's settings.
pub fn get_working_directory(
    workspace: &Workspace,
    cx: &AppContext,
    strategy: WorkingDirectory,
) -> Option<PathBuf> {
    let res = match strategy {
        WorkingDirectory::CurrentProjectDirectory => current_project_directory(workspace, cx)
            .or_else(|| first_project_directory(workspace, cx)),
        WorkingDirectory::FirstProjectDirectory => first_project_directory(workspace, cx),
        WorkingDirectory::AlwaysHome => None,
        WorkingDirectory::Always { directory } => {
            shellexpand::full(&directory) //TODO handle this better
                .ok()
                .map(|dir| Path::new(&dir.to_string()).to_path_buf())
                .filter(|dir| dir.is_dir())
        }
    };
    res.or_else(home_dir)
}

///Get's the first project's home directory, or the home directory
fn first_project_directory(workspace: &Workspace, cx: &AppContext) -> Option<PathBuf> {
    workspace
        .worktrees(cx)
        .next()
        .and_then(|worktree_handle| worktree_handle.read(cx).as_local())
        .and_then(get_path_from_wt)
}

///Gets the intuitively correct working directory from the given workspace
///If there is an active entry for this project, returns that entry's worktree root.
///If there's no active entry but there is a worktree, returns that worktrees root.
///If either of these roots are files, or if there are any other query failures,
///  returns the user's home directory
fn current_project_directory(workspace: &Workspace, cx: &AppContext) -> Option<PathBuf> {
    let project = workspace.project().read(cx);

    project
        .active_entry()
        .and_then(|entry_id| project.worktree_for_entry(entry_id, cx))
        .or_else(|| workspace.worktrees(cx).next())
        .and_then(|worktree_handle| worktree_handle.read(cx).as_local())
        .and_then(get_path_from_wt)
}

fn get_path_from_wt(wt: &LocalWorktree) -> Option<PathBuf> {
    wt.root_entry()
        .filter(|re| re.is_dir())
        .map(|_| wt.abs_path().to_path_buf())
}

#[cfg(test)]
mod tests {

    use super::*;
    use gpui::TestAppContext;
    use project::{Entry, Project, ProjectPath, Worktree};
    use workspace::AppState;

    use std::path::Path;

    ///Working directory calculation tests

    ///No Worktrees in project -> home_dir()
    #[gpui::test]
    async fn no_worktree(cx: &mut TestAppContext) {
        //Setup variables
        let (project, workspace) = blank_workspace(cx).await;
        //Test
        cx.read(|cx| {
            let workspace = workspace.read(cx);
            let active_entry = project.read(cx).active_entry();

            //Make sure enviroment is as expeted
            assert!(active_entry.is_none());
            assert!(workspace.worktrees(cx).next().is_none());

            let res = current_project_directory(workspace, cx);
            assert_eq!(res, None);
            let res = first_project_directory(workspace, cx);
            assert_eq!(res, None);
        });
    }

    ///No active entry, but a worktree, worktree is a file -> home_dir()
    #[gpui::test]
    async fn no_active_entry_worktree_is_file(cx: &mut TestAppContext) {
        //Setup variables

        let (project, workspace) = blank_workspace(cx).await;
        create_file_wt(project.clone(), "/root.txt", cx).await;

        cx.read(|cx| {
            let workspace = workspace.read(cx);
            let active_entry = project.read(cx).active_entry();

            //Make sure enviroment is as expeted
            assert!(active_entry.is_none());
            assert!(workspace.worktrees(cx).next().is_some());

            let res = current_project_directory(workspace, cx);
            assert_eq!(res, None);
            let res = first_project_directory(workspace, cx);
            assert_eq!(res, None);
        });
    }

    //No active entry, but a worktree, worktree is a folder -> worktree_folder
    #[gpui::test]
    async fn no_active_entry_worktree_is_dir(cx: &mut TestAppContext) {
        //Setup variables
        let (project, workspace) = blank_workspace(cx).await;
        let (_wt, _entry) = create_folder_wt(project.clone(), "/root/", cx).await;

        //Test
        cx.update(|cx| {
            let workspace = workspace.read(cx);
            let active_entry = project.read(cx).active_entry();

            assert!(active_entry.is_none());
            assert!(workspace.worktrees(cx).next().is_some());

            let res = current_project_directory(workspace, cx);
            assert_eq!(res, Some((Path::new("/root/")).to_path_buf()));
            let res = first_project_directory(workspace, cx);
            assert_eq!(res, Some((Path::new("/root/")).to_path_buf()));
        });
    }

    //Active entry with a work tree, worktree is a file -> home_dir()
    #[gpui::test]
    async fn active_entry_worktree_is_file(cx: &mut TestAppContext) {
        //Setup variables

        let (project, workspace) = blank_workspace(cx).await;
        let (_wt, _entry) = create_folder_wt(project.clone(), "/root1/", cx).await;
        let (wt2, entry2) = create_file_wt(project.clone(), "/root2.txt", cx).await;
        insert_active_entry_for(wt2, entry2, project.clone(), cx);

        //Test
        cx.update(|cx| {
            let workspace = workspace.read(cx);
            let active_entry = project.read(cx).active_entry();

            assert!(active_entry.is_some());

            let res = current_project_directory(workspace, cx);
            assert_eq!(res, None);
            let res = first_project_directory(workspace, cx);
            assert_eq!(res, Some((Path::new("/root1/")).to_path_buf()));
        });
    }

    //Active entry, with a worktree, worktree is a folder -> worktree_folder
    #[gpui::test]
    async fn active_entry_worktree_is_dir(cx: &mut TestAppContext) {
        //Setup variables
        let (project, workspace) = blank_workspace(cx).await;
        let (_wt, _entry) = create_folder_wt(project.clone(), "/root1/", cx).await;
        let (wt2, entry2) = create_folder_wt(project.clone(), "/root2/", cx).await;
        insert_active_entry_for(wt2, entry2, project.clone(), cx);

        //Test
        cx.update(|cx| {
            let workspace = workspace.read(cx);
            let active_entry = project.read(cx).active_entry();

            assert!(active_entry.is_some());

            let res = current_project_directory(workspace, cx);
            assert_eq!(res, Some((Path::new("/root2/")).to_path_buf()));
            let res = first_project_directory(workspace, cx);
            assert_eq!(res, Some((Path::new("/root1/")).to_path_buf()));
        });
    }

    ///Creates a worktree with 1 file: /root.txt
    pub async fn blank_workspace(
        cx: &mut TestAppContext,
    ) -> (ModelHandle<Project>, ViewHandle<Workspace>) {
        let params = cx.update(AppState::test);

        let project = Project::test(params.fs.clone(), [], cx).await;
        let (_, workspace) = cx.add_window(|cx| {
            Workspace::new(
                Default::default(),
                0,
                project.clone(),
                |_, _| unimplemented!(),
                cx,
            )
        });

        (project, workspace)
    }

    ///Creates a worktree with 1 folder: /root{suffix}/
    async fn create_folder_wt(
        project: ModelHandle<Project>,
        path: impl AsRef<Path>,
        cx: &mut TestAppContext,
    ) -> (ModelHandle<Worktree>, Entry) {
        create_wt(project, true, path, cx).await
    }

    ///Creates a worktree with 1 file: /root{suffix}.txt
    async fn create_file_wt(
        project: ModelHandle<Project>,
        path: impl AsRef<Path>,
        cx: &mut TestAppContext,
    ) -> (ModelHandle<Worktree>, Entry) {
        create_wt(project, false, path, cx).await
    }

    async fn create_wt(
        project: ModelHandle<Project>,
        is_dir: bool,
        path: impl AsRef<Path>,
        cx: &mut TestAppContext,
    ) -> (ModelHandle<Worktree>, Entry) {
        let (wt, _) = project
            .update(cx, |project, cx| {
                project.find_or_create_local_worktree(path, true, cx)
            })
            .await
            .unwrap();

        let entry = cx
            .update(|cx| {
                wt.update(cx, |wt, cx| {
                    wt.as_local()
                        .unwrap()
                        .create_entry(Path::new(""), is_dir, cx)
                })
            })
            .await
            .unwrap();

        (wt, entry)
    }

    pub fn insert_active_entry_for(
        wt: ModelHandle<Worktree>,
        entry: Entry,
        project: ModelHandle<Project>,
        cx: &mut TestAppContext,
    ) {
        cx.update(|cx| {
            let p = ProjectPath {
                worktree_id: wt.read(cx).id(),
                path: entry.path,
            };
            project.update(cx, |project, cx| project.set_active_path(Some(p), cx));
        });
    }
}