mod event;
#[cfg(target_os = "macos")]
pub mod mac;
pub mod test;
pub mod current {
    #[cfg(target_os = "macos")]
    pub use super::mac::*;
}

use crate::{
    executor,
    fonts::{FontId, GlyphId, Metrics as FontMetrics, Properties as FontProperties},
    geometry::{
        rect::{RectF, RectI},
        vector::Vector2F,
    },
    keymap,
    text_layout::{LineLayout, RunStyle},
    Action, ClipboardItem, Menu, Scene,
};
use anyhow::{anyhow, Result};
use async_task::Runnable;
pub use event::{Event, NavigationDirection};
use postage::oneshot;
use serde::Deserialize;
use std::{
    any::Any,
    fmt::{self, Display},
    path::{Path, PathBuf},
    rc::Rc,
    str::FromStr,
    sync::Arc,
};
use time::UtcOffset;

pub trait Platform: Send + Sync {
    fn dispatcher(&self) -> Arc<dyn Dispatcher>;
    fn fonts(&self) -> Arc<dyn FontSystem>;

    fn activate(&self, ignoring_other_apps: bool);
    fn open_window(
        &self,
        id: usize,
        options: WindowOptions,
        executor: Rc<executor::Foreground>,
    ) -> Box<dyn Window>;
    fn key_window_id(&self) -> Option<usize>;
    fn quit(&self);

    fn write_to_clipboard(&self, item: ClipboardItem);
    fn read_from_clipboard(&self) -> Option<ClipboardItem>;
    fn open_url(&self, url: &str);

    fn write_credentials(&self, url: &str, username: &str, password: &[u8]) -> Result<()>;
    fn read_credentials(&self, url: &str) -> Result<Option<(String, Vec<u8>)>>;
    fn delete_credentials(&self, url: &str) -> Result<()>;

    fn set_cursor_style(&self, style: CursorStyle);

    fn local_timezone(&self) -> UtcOffset;

    fn path_for_auxiliary_executable(&self, name: &str) -> Result<PathBuf>;
    fn app_path(&self) -> Result<PathBuf>;
    fn app_version(&self) -> Result<AppVersion>;
}

pub(crate) trait ForegroundPlatform {
    fn on_become_active(&self, callback: Box<dyn FnMut()>);
    fn on_resign_active(&self, callback: Box<dyn FnMut()>);
    fn on_quit(&self, callback: Box<dyn FnMut()>);
    fn on_event(&self, callback: Box<dyn FnMut(Event) -> bool>);
    fn on_open_urls(&self, callback: Box<dyn FnMut(Vec<String>)>);
    fn run(&self, on_finish_launching: Box<dyn FnOnce() -> ()>);

    fn on_menu_command(&self, callback: Box<dyn FnMut(&dyn Action)>);
    fn on_validate_menu_command(&self, callback: Box<dyn FnMut(&dyn Action) -> bool>);
    fn on_will_open_menu(&self, callback: Box<dyn FnMut()>);
    fn set_menus(&self, menus: Vec<Menu>, matcher: &keymap::Matcher);
    fn prompt_for_paths(
        &self,
        options: PathPromptOptions,
    ) -> oneshot::Receiver<Option<Vec<PathBuf>>>;
    fn prompt_for_new_path(&self, directory: &Path) -> oneshot::Receiver<Option<PathBuf>>;
}

pub trait Dispatcher: Send + Sync {
    fn is_main_thread(&self) -> bool;
    fn run_on_main_thread(&self, task: Runnable);
}

pub trait Window: WindowContext {
    fn as_any_mut(&mut self) -> &mut dyn Any;
    fn on_event(&mut self, callback: Box<dyn FnMut(Event)>);
    fn on_active_status_change(&mut self, callback: Box<dyn FnMut(bool)>);
    fn on_resize(&mut self, callback: Box<dyn FnMut()>);
    fn on_close(&mut self, callback: Box<dyn FnOnce()>);
    fn prompt(&self, level: PromptLevel, msg: &str, answers: &[&str]) -> oneshot::Receiver<usize>;
    fn activate(&self);
    fn set_title(&mut self, title: &str);
}

pub trait WindowContext {
    fn size(&self) -> Vector2F;
    fn scale_factor(&self) -> f32;
    fn titlebar_height(&self) -> f32;
    fn present_scene(&mut self, scene: Scene);
}

#[derive(Debug)]
pub struct WindowOptions<'a> {
    pub bounds: WindowBounds,
    pub title: Option<&'a str>,
    pub titlebar_appears_transparent: bool,
    pub traffic_light_position: Option<Vector2F>,
}

#[derive(Debug)]
pub enum WindowBounds {
    Maximized,
    Fixed(RectF),
}

pub struct PathPromptOptions {
    pub files: bool,
    pub directories: bool,
    pub multiple: bool,
}

pub enum PromptLevel {
    Info,
    Warning,
    Critical,
}

#[derive(Copy, Clone, Debug, Deserialize)]
pub enum CursorStyle {
    Arrow,
    ResizeLeftRight,
    PointingHand,
    IBeam,
}

#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord)]
pub struct AppVersion {
    major: usize,
    minor: usize,
    patch: usize,
}

impl FromStr for AppVersion {
    type Err = anyhow::Error;

    fn from_str(s: &str) -> Result<Self> {
        let mut components = s.trim().split('.');
        let major = components
            .next()
            .ok_or_else(|| anyhow!("missing major version number"))?
            .parse()?;
        let minor = components
            .next()
            .ok_or_else(|| anyhow!("missing minor version number"))?
            .parse()?;
        let patch = components
            .next()
            .ok_or_else(|| anyhow!("missing patch version number"))?
            .parse()?;
        Ok(Self {
            major,
            minor,
            patch,
        })
    }
}

impl Display for AppVersion {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "{}.{}.{}", self.major, self.minor, self.patch)
    }
}

#[derive(Copy, Clone, Debug)]
pub enum RasterizationOptions {
    Alpha,
    Bgra,
}

pub trait FontSystem: Send + Sync {
    fn add_fonts(&self, fonts: &[Arc<Vec<u8>>]) -> anyhow::Result<()>;
    fn load_family(&self, name: &str) -> anyhow::Result<Vec<FontId>>;
    fn select_font(
        &self,
        font_ids: &[FontId],
        properties: &FontProperties,
    ) -> anyhow::Result<FontId>;
    fn font_metrics(&self, font_id: FontId) -> FontMetrics;
    fn typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> anyhow::Result<RectF>;
    fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> anyhow::Result<Vector2F>;
    fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId>;
    fn rasterize_glyph(
        &self,
        font_id: FontId,
        font_size: f32,
        glyph_id: GlyphId,
        subpixel_shift: Vector2F,
        scale_factor: f32,
        options: RasterizationOptions,
    ) -> Option<(RectI, Vec<u8>)>;
    fn layout_line(&self, text: &str, font_size: f32, runs: &[(usize, RunStyle)]) -> LineLayout;
    fn wrap_line(&self, text: &str, font_id: FontId, font_size: f32, width: f32) -> Vec<usize>;
}

impl<'a> Default for WindowOptions<'a> {
    fn default() -> Self {
        Self {
            bounds: WindowBounds::Maximized,
            title: Default::default(),
            titlebar_appears_transparent: Default::default(),
            traffic_light_position: Default::default(),
        }
    }
}
