feat: simplify theme

this should keep it from printing "no image to allocate"
each time when started without an argument

src/main.rs

@@ -1,7 +1,7 @@
-use std::{env, path::Path};
+use std::{borrow::Cow, env, ffi::OsStr, path::Path};
 
 use iced::{
-    Alignment, Color, Element, Length, Renderer, Subscription, Task, Theme, color, event,
+    Alignment, Color, Element, Length, Renderer, Subscription, Task, Theme, event,
     keyboard::{self, Key, key},
     theme, widget, window,
 };
@@ -20,44 +20,53 @@ enum Message {
 struct State {
     image: Option<RgbaImage>,
     image_display: Option<widget::image::Allocation>,
+    image_filter: widget::image::FilterMethod,
 
     error: Option<String>,
+    info: Option<String>,
+    infobar_shown: bool,
 }
 impl State {
     fn new() -> (Self, Task<Message>) {
         let mut state = State::default();
 
-        state.error = env::args().nth(1).and_then(|path| {
-            utils::load_image(path)
-                .map(|image| state.image = Some(image))
-                .err()
-        });
-        let allocate_image = state.allocate_image();
+        if let Some(path) = env::args().nth(1) {
+            match state.load_image(path) {
+                Err(e) => state.error = Some(e),
+                Ok(task) => return (state, task),
+            }
+        }
 
-        (state, allocate_image)
+        (state, Task::none())
     }
     fn view(&self) -> Element<'_, Message, Theme, Renderer> {
-        widget::column([
-            if let Some(allocation) = self.image_display.as_ref() {
-                widget::image::viewer(allocation.handle().clone())
-                    .width(Length::Fill)
-                    .height(Length::Fill)
-                    .into()
-            } else {
-                widget::container(widget::text(include_str!("usage.txt")))
-                    .height(Length::Fill)
-                    .width(Length::Fill)
-                    .align_x(Alignment::Center)
-                    .align_y(Alignment::Center)
-                    .into()
-            },
-            if let Some(error) = self.error.as_ref() {
-                widget::text(error).style(widget::text::danger).into()
-            } else {
-                widget::space().into()
-            },
-        ])
-        .into()
+        let mut main = Vec::new();
+
+        main.push(if let Some(allocation) = self.image_display.as_ref() {
+            widget::image::viewer(allocation.handle().clone())
+                .filter_method(self.image_filter)
+                .max_scale(50.)
+                .min_scale(1.)
+                .width(Length::Fill)
+                .height(Length::Fill)
+                .into()
+        } else {
+            widget::container(widget::text(include_str!("usage.txt")))
+                .height(Length::Fill)
+                .width(Length::Fill)
+                .align_x(Alignment::Center)
+                .align_y(Alignment::Center)
+                .into()
+        });
+
+        if let Some(error) = self.error.as_ref() {
+            main.push(widget::text(error).style(widget::text::danger).into());
+        }
+        if self.infobar_shown && self.info.is_some() {
+            main.push(widget::text(self.title()).into());
+        }
+
+        widget::column(main).into()
     }
     fn update(&mut self, message: Message) -> Task<Message> {
         match message {
@@ -107,6 +116,15 @@ impl State {
                         }
                     };
                 }
+                Key::Character("f") => {
+                    self.image_filter = match self.image_filter {
+                        widget::image::FilterMethod::Linear => widget::image::FilterMethod::Nearest,
+                        widget::image::FilterMethod::Nearest => widget::image::FilterMethod::Linear,
+                    }
+                }
+                Key::Character("b") => {
+                    self.infobar_shown = !self.infobar_shown;
+                }
 
                 Key::Character("s") => {
                     self.save_image();
@@ -136,7 +154,16 @@ impl State {
     }
 
     fn load_image(&mut self, path: impl AsRef<Path>) -> Result<Task<Message>, String> {
-        utils::load_image(path).map(|image| {
+        utils::load_image(&path).map(|image| {
+            self.info = Some(format!(
+                "{} {}x{}",
+                path.as_ref()
+                    .file_name()
+                    .map(OsStr::to_string_lossy)
+                    .unwrap_or(Cow::Borrowed("[no file]")),
+                image.width(),
+                image.height(),
+            ));
             self.image = Some(image);
             self.allocate_image()
         })
@@ -167,8 +194,11 @@ impl State {
         event::listen().map(Message::Event)
     }
     fn title(&self) -> String {
-        match self.image.as_ref() {
-            Some(image) => format!("imagey {}x{}", image.width(), image.height()),
+        match self.info.as_ref() {
+            Some(info) => format!(
+                "imagey {info} {}",
+                utils::string_from_filter_type(self.image_filter),
+            ),
             None => "imagey".into(),
         }
     }
@@ -183,12 +213,9 @@ fn main() -> Result<(), iced::Error> {
         .theme(Theme::custom(
             "custom",
             theme::Palette {
-                background: color!(0x080808),
+                background: Color::BLACK,
                 text: Color::WHITE,
-                primary: color!(0xff00ff),
-                success: color!(0x00ff00),
-                warning: color!(0x880000),
-                danger: color!(0xff0000),
+                ..theme::Palette::DARK
             },
         ))
         .run()

src/utils.rs

@@ -1,5 +1,6 @@
 use std::path::{Path, PathBuf};
 
+use iced::widget;
 use image::{DynamicImage, ImageDecoder, ImageReader, RgbaImage};
 use rfd::FileDialog;
 
@@ -79,3 +80,10 @@ pub fn save_image(image: Option<&RgbaImage>) -> Result<(), String> {
 
     Ok(())
 }
+
+pub fn string_from_filter_type(f: widget::image::FilterMethod) -> &'static str {
+    match f {
+        widget::image::FilterMethod::Linear => "bilinear",
+        widget::image::FilterMethod::Nearest => "nearest neighbor",
+    }
+}