From 5234fe20b52109b88ad764ca215424e156f56e10 Mon Sep 17 00:00:00 2001
From: Ivan Li <ivanli2048@gmail.com>
Date: Thu, 9 Jun 2022 20:07:22 +0800
Subject: [PATCH] feat: change screen to optional. Issue #1.

---
 src/screen.rs | 99 +++++++++++++++++++++++++++++----------------------
 1 file changed, 56 insertions(+), 43 deletions(-)

diff --git a/src/screen.rs b/src/screen.rs
index e924580..99f8f14 100644
--- a/src/screen.rs
+++ b/src/screen.rs
@@ -1,18 +1,19 @@
-use anyhow::{anyhow, Result};
+use anyhow::{anyhow, Result, Ok};
 use embedded_graphics::{
-    mono_font::{ascii::FONT_10X20, MonoTextStyle, iso_8859_10::FONT_6X10},
+    mono_font::{ascii::FONT_10X20, iso_8859_10::FONT_6X10, MonoTextStyle},
     pixelcolor::Rgb565,
     prelude::{Dimensions, Drawable, Point, Primitive, RgbColor},
     primitives::{PrimitiveStyleBuilder, Rectangle},
     text::Text,
 };
-use embedded_hal::delay::blocking::DelayUs;
+use embedded_hal::{delay::blocking::DelayUs, i2c::blocking::{I2c, Operation}};
 use esp_idf_hal::{
     delay,
     gpio::{self},
     i2c::{self, Master, I2C0},
     prelude::*,
 };
+use log::warn;
 use ssd1306::{
     mode::{BufferedGraphicsMode, DisplayConfig},
     prelude::I2CInterface,
@@ -27,7 +28,7 @@ type Display = Ssd1306<
 >;
 
 pub struct Screen {
-    pub display: Display,
+    pub display: Option<Display>,
 }
 
 impl Screen {
@@ -37,13 +38,21 @@ impl Screen {
         scl: gpio::Gpio10<gpio::Unknown>,
     ) -> Result<Self> {
         let config = <i2c::config::MasterConfig as Default>::default().baudrate(400.kHz().into());
-        let i2c = i2c::Master::<i2c::I2C0, _, _>::new(
-            i2c,
-            i2c::MasterPins { sda, scl },
-            config,
-        )?;
+        let mut i2c = i2c::Master::<i2c::I2C0, _, _>::new(i2c, i2c::MasterPins { sda, scl }, config)?;
+        
+        let mut buff = [0u8; 10];
+        if let Err(err) = i2c.transaction(0x3C, &mut [Operation::Read(&mut buff)]) {
+            warn!("Failed to initialize display: {}", err);
+            warn!("Failed to initialize display: {}", err);
+            warn!("Failed to initialize display: {}", err);
+            warn!("Failed to initialize display: {}", err);
+            warn!("Failed to initialize display: {}", err);
+            return Ok(Self { display: None });
+        }
+
         let di = ssd1306::I2CDisplayInterface::new(i2c);
 
+
         let mut delay = delay::Ets;
         delay.delay_ms(10_u32)?;
 
@@ -55,22 +64,27 @@ impl Screen {
         .into_buffered_graphics_mode();
 
         display
-            .init().map_err(|err| anyhow!("Can not init display: {:?}", err))?;
+            .init()
+            .map_err(|err| anyhow!("Can not init display: {:?}", err))?;
 
-        let mut instance = Screen { display };
+        let mut instance = Screen { display: Some(display) };
 
         instance.draw_boot()?;
 
         Ok(instance)
     }
 
-    pub fn draw_boot(&mut self) -> Result<()>
-    {
-        self.display.clear();
+    pub fn draw_boot(&mut self) -> Result<()> {
+        if self.display.is_none() {
+            return Ok(());
+        }
+        let display = self.display.as_mut().unwrap();
+
+        display.clear();
 
         Rectangle::new(
-            self.display.bounding_box().top_left,
-            self.display.bounding_box().size,
+            display.bounding_box().top_left,
+            display.bounding_box().size,
         )
         .into_styled(
             PrimitiveStyleBuilder::new()
@@ -79,19 +93,21 @@ impl Screen {
                 .stroke_width(1)
                 .build(),
         )
-        .draw(&mut self.display).expect("Failed to draw rectangle");
+        .draw(display)
+        .expect("Failed to draw rectangle");
 
         Text::new(
             "Ivan's UPS",
             Point::new(
                 12,
-                (self.display.bounding_box().size.height - 10) as i32 / 2 + 1,
+                (display.bounding_box().size.height - 10) as i32 / 2 + 1,
             ),
             MonoTextStyle::new(&FONT_10X20, Rgb565::WHITE.into()),
         )
-        .draw(&mut self.display).expect("Failed to draw text");
+        .draw(display)
+        .expect("Failed to draw text");
 
-        self.display
+        display
             .flush()
             .map_err(|e| anyhow::anyhow!("Display error: {:?}", e))?;
 
@@ -99,30 +115,27 @@ impl Screen {
     }
 
     pub fn draw_voltage(&mut self, adapter: f32, battery: f32) -> Result<()> {
-        self.display.clear();
+        if let Some(display) = self.display.as_mut() {
+            display.clear();
 
-        Text::new(
-            format!("Adp. {:.2} mV", adapter).as_str(),
-            Point::new(
-                12,
-                24,
-            ),
-            MonoTextStyle::new(&FONT_6X10, Rgb565::WHITE.into()),
-        )
-        .draw(&mut self.display).expect("Failed to draw text");
-        Text::new(
-            format!("Bat. {:.2} mV", battery).as_str(),
-            Point::new(
-                12,
-                36,
-            ),
-            MonoTextStyle::new(&FONT_6X10, Rgb565::WHITE.into()),
-        )
-        .draw(&mut self.display).expect("Failed to draw text");
-
-        self.display
-            .flush()
-            .map_err(|e| anyhow::anyhow!("Display error: {:?}", e))?;
+            Text::new(
+                format!("Adp. {:.2} mV", adapter).as_str(),
+                Point::new(12, 24),
+                MonoTextStyle::new(&FONT_6X10, Rgb565::WHITE.into()),
+            )
+            .draw(display)
+            .expect("Failed to draw text");
+            Text::new(
+                format!("Bat. {:.2} mV", battery).as_str(),
+                Point::new(12, 36),
+                MonoTextStyle::new(&FONT_6X10, Rgb565::WHITE.into()),
+            )
+            .draw(display)
+            .expect("Failed to draw text");
+            display
+                .flush()
+                .map_err(|e| anyhow::anyhow!("Display error: {:?}", e))?;
+        }
 
         Ok(())
     }