fix: detect light theme only by env var (#177)

5 files changed, 51 insertions, 268 deletions

diff --git a/Cargo.lock b/Cargo.lock
index fefa9a8..e4bddc8 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -30,6 +30,7 @@ dependencies = [
 name = "aichat"
 version = "0.9.0-rc2"
 dependencies = [
+ "ansi_colours",
  "anyhow",
  "arboard",
  "async-trait",
@@ -78,6 +79,15 @@ dependencies = [
 ]
 
 [[package]]
+name = "ansi_colours"
+version = "1.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6a1558bd2075d341b9ca698ec8eb6fcc55a746b1fc4255585aad5b141d918a80"
+dependencies = [
+ "rgb",
+]
+
+[[package]]
 name = "anstream"
 version = "0.6.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -252,6 +262,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7f30e7476521f6f8af1a1c4c0b8cc94f0bee37d91763d0ca2665f299b6cd8aec"
 
 [[package]]
+name = "bytemuck"
+version = "1.14.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "374d28ec25809ee0e23827c2ab573d729e293f281dfe393500e7ad618baa61c6"
+
+[[package]]
 name = "bytes"
 version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1357,6 +1373,15 @@ dependencies = [
 ]
 
 [[package]]
+name = "rgb"
+version = "0.8.37"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "05aaa8004b64fd573fc9d002f4e632d51ad4f026c2b5ba95fcb6c2f32c2c47d8"
+dependencies = [
+ "bytemuck",
+]
+
+[[package]]
 name = "ring"
 version = "0.17.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/Cargo.toml b/Cargo.toml
index 29cc568..7380eff 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -23,7 +23,7 @@ reedline = "0.21.0"
 serde = { version = "1.0.152", features = ["derive"] }
 serde_json = "1.0.93"
 serde_yaml = "0.9.17"
-tokio = { version = "1.26.0", features = ["rt", "time", "macros", "signal", "io-std"] }
+tokio = { version = "1.26.0", features = ["rt", "time", "macros", "signal"] }
 crossbeam = "0.8.2"
 crossterm = "0.26.1"
 chrono = "0.4.23"
@@ -39,6 +39,7 @@ nu-ansi-term = "0.47.0"
 arboard = { version = "3.2.0", default-features = false }
 async-trait = "0.1.74"
 textwrap = "0.16.0"
+ansi_colours = "1.2.2"
 
 [dependencies.reqwest]
 version = "0.11.14"
diff --git a/src/config/mod.rs b/src/config/mod.rs
index 0af432c..ed256e6 100644
--- a/src/config/mod.rs
+++ b/src/config/mod.rs
@@ -10,7 +10,7 @@ use crate::client::openai::{OpenAIClient, OpenAIConfig};
 use crate::client::{all_clients, create_client_config, list_models, ClientConfig, ModelInfo};
 use crate::config::message::num_tokens_from_messages;
 use crate::render::RenderOptions;
-use crate::utils::{get_env_name, now};
+use crate::utils::{get_env_name, light_theme_from_colorfgbg, now};
 
 use anyhow::{anyhow, bail, Context, Result};
 use inquire::{Confirm, Select, Text};
@@ -592,13 +592,11 @@ impl Config {
         if let Ok(value) = env::var(get_env_name("light_theme")) {
             set_bool(&mut self.light_theme, &value);
             return Ok(());
-        }
-        #[cfg(not(target_os = "windows"))]
-        if let Ok(crate::utils::termbg::Theme::Light) =
-            crate::utils::termbg::theme(std::time::Duration::from_millis(200))
-        {
-            self.light_theme = true;
-        }
+        } else if let Ok(value) = env::var("COLORFGBG") {
+            if let Some(light) = light_theme_from_colorfgbg(&value) {
+                self.light_theme = light
+            }
+        };
         Ok(())
     }
 
diff --git a/src/utils/mod.rs b/src/utils/mod.rs
index fa26dcf..699f8a0 100644
--- a/src/utils/mod.rs
+++ b/src/utils/mod.rs
@@ -1,5 +1,3 @@
-#[cfg(not(target_os = "windows"))]
-pub(crate) mod termbg;
 mod tiktoken;
 
 use self::tiktoken::cl100k_base;
@@ -45,3 +43,21 @@ pub fn split_text(text: &str) -> Result<Vec<String>, anyhow::Error> {
     let data: Result<Vec<String>, _> = tokens.into_iter().map(|v| bpe.decode(&[v])).collect();
     data
 }
+
+pub fn light_theme_from_colorfgbg(colorfgbg: &str) -> Option<bool> {
+    let parts: Vec<_> = colorfgbg.split(';').collect();
+    let bg = match parts.len() {
+        2 => &parts[1],
+        3 => &parts[2],
+        _ => {
+            return None;
+        }
+    };
+    let bg = bg.parse::<u8>().ok()?;
+    let (r, g, b) = ansi_colours::rgb_from_ansi256(bg);
+
+    let v = 0.2126 * r as f32 + 0.7152 * g as f32 + 0.0722 * b as f32;
+
+    let light = v > 128.0;
+    Some(light)
+}
diff --git a/src/utils/termbg.rs b/src/utils/termbg.rs
deleted file mode 100644
index 2322227..0000000
--- a/src/utils/termbg.rs
+++ /dev/null
@@ -1,257 +0,0 @@
-//! Terminal background color detection
-/// Fork from https://github.com/dalance/termbg/blob/v0.4.3/src/lib.rs
-use anyhow::{anyhow, Error, Result};
-use crossterm::terminal;
-use std::env;
-use std::io::{self, Read, Write};
-use std::time::Duration;
-
-/// Terminal
-#[derive(Copy, Clone, Debug, PartialEq)]
-pub enum Terminal {
-    Screen,
-    Tmux,
-    XtermCompatible,
-    VSCode,
-    Emacs,
-}
-
-/// 16bit RGB color
-#[derive(Copy, Clone, Debug)]
-pub struct Rgb {
-    pub r: u16,
-    pub g: u16,
-    pub b: u16,
-}
-
-/// Background theme
-#[derive(Copy, Clone, Debug)]
-pub enum Theme {
-    Light,
-    Dark,
-}
-
-/// get detected termnial
-pub fn terminal() -> Terminal {
-    if let Ok(term_program) = env::var("TERM_PROGRAM") {
-        if term_program == "vscode" {
-            return Terminal::VSCode;
-        }
-    }
-
-    if env::var("INSIDE_EMACS").is_ok() {
-        return Terminal::Emacs;
-    }
-
-    if env::var("TMUX").is_ok() {
-        Terminal::Tmux
-    } else {
-        let is_screen = if let Ok(term) = env::var("TERM") {
-            term.starts_with("screen")
-        } else {
-            false
-        };
-        if is_screen {
-            Terminal::Screen
-        } else {
-            Terminal::XtermCompatible
-        }
-    }
-}
-
-/// get background color by `RGB`
-pub fn rgb(timeout: Duration) -> Result<Rgb> {
-    let term = terminal();
-    let rgb = match term {
-        Terminal::VSCode => Err(unsupported_err()),
-        Terminal::Emacs => Err(unsupported_err()),
-        _ => from_xterm(term, timeout),
-    };
-    check_rgb(rgb)
-}
-
-/// get background color by `Theme`
-pub fn theme(timeout: Duration) -> Result<Theme> {
-    let rgb = rgb(timeout)?;
-
-    // ITU-R BT.601
-    let y = rgb.r as f64 * 0.299 + rgb.g as f64 * 0.587 + rgb.b as f64 * 0.114;
-
-    if y > 32768.0 {
-        Ok(Theme::Light)
-    } else {
-        Ok(Theme::Dark)
-    }
-}
-
-fn from_xterm(term: Terminal, timeout: Duration) -> Result<Rgb> {
-    // Query by XTerm control sequence
-    let query = if term == Terminal::Tmux {
-        "\x1bPtmux;\x1b\x1b]11;?\x07\x1b\\\x03"
-    } else if term == Terminal::Screen {
-        "\x1bP\x1b]11;?\x07\x1b\\\x03"
-    } else {
-        "\x1b]11;?\x1b\\"
-    };
-
-    let mut stderr = io::stderr();
-    terminal::enable_raw_mode()?;
-    write!(stderr, "{}", query)?;
-    stderr.flush()?;
-
-    let mut stdin = io::stdin();
-
-    let (tx, rx) = std::sync::mpsc::channel();
-
-    std::thread::spawn(move || {
-        let mut buffer = Vec::new();
-        let mut buf = [0; 1];
-        let mut start = false;
-        loop {
-            let _ = stdin.read_exact(&mut buf);
-            // response terminated by BEL(0x7)
-            if start && (buf[0] == 0x7) {
-                break;
-            }
-            // response terminated by ST(0x1b 0x5c)
-            if start && (buf[0] == 0x1b) {
-                // consume last 0x5c
-                let _ = stdin.read_exact(&mut buf);
-                debug_assert_eq!(buf[0], 0x5c);
-                break;
-            }
-            if start {
-                buffer.push(buf[0]);
-            }
-            if buf[0] == b':' {
-                start = true;
-            }
-        }
-        // Ignore send error because timeout may be occured
-        let _ = tx.send(buffer);
-    });
-
-    let buffer = rx.recv_timeout(timeout);
-
-    terminal::disable_raw_mode()?;
-
-    let buffer = buffer?;
-
-    let s = String::from_utf8_lossy(&buffer);
-    let (r, g, b) = decode_x11_color(&s)?;
-    Ok(Rgb { r, g, b })
-}
-
-fn decode_x11_color(s: &str) -> Result<(u16, u16, u16)> {
-    fn decode_hex(s: &str) -> Result<u16> {
-        let len = s.len() as u32;
-        let mut ret = u16::from_str_radix(s, 16).map_err(|_| parse_err(s))?;
-        ret <<= (4 - len) * 4;
-        Ok(ret)
-    }
-
-    let rgb: Vec<_> = s.split('/').collect();
-
-    let r = rgb.first().ok_or_else(|| parse_err(s))?;
-    let g = rgb.get(1).ok_or_else(|| parse_err(s))?;
-    let b = rgb.get(2).ok_or_else(|| parse_err(s))?;
-    let r = decode_hex(r)?;
-    let g = decode_hex(g)?;
-    let b = decode_hex(b)?;
-
-    Ok((r, g, b))
-}
-
-fn check_rgb(prev: Result<Rgb>) -> Result<Rgb> {
-    if prev.is_ok() {
-        return prev;
-    }
-    let fallback = from_env_colorfgbg();
-    if fallback.is_ok() {
-        return fallback;
-    }
-    prev
-}
-
-fn from_env_colorfgbg() -> Result<Rgb> {
-    let var = env::var("COLORFGBG").map_err(|_| unsupported_err())?;
-    let fgbg: Vec<_> = var.split(';').collect();
-    let bg = fgbg.get(1).ok_or(unsupported_err())?;
-    let bg = bg.parse::<u8>().map_err(|_| parse_err(&var))?;
-
-    // rxvt default color table
-    let (r, g, b) = match bg {
-        // black
-        0 => (0, 0, 0),
-        // red
-        1 => (205, 0, 0),
-        // green
-        2 => (0, 205, 0),
-        // yellow
-        3 => (205, 205, 0),
-        // blue
-        4 => (0, 0, 238),
-        // magenta
-        5 => (205, 0, 205),
-
-        // cyan
-        6 => (0, 205, 205),
-        // white
-        7 => (229, 229, 229),
-        // bright black
-        8 => (127, 127, 127),
-        // bright red
-        9 => (255, 0, 0),
-        // bright green
-        10 => (0, 255, 0),
-        // bright yellow
-        11 => (255, 255, 0),
-        // bright blue
-        12 => (92, 92, 255),
-        // bright magenta
-        13 => (255, 0, 255),
-        // bright cyan
-        14 => (0, 255, 255),
-
-        // bright white
-        15 => (255, 255, 255),
-        _ => (0, 0, 0),
-    };
-
-    Ok(Rgb {
-        r: r * 256,
-        g: g * 256,
-        b: b * 256,
-    })
-}
-
-fn unsupported_err() -> Error {
-    anyhow!("Unsupported terminal")
-}
-
-fn parse_err(value: &str) -> Error {
-    anyhow!("Failed to parse {value}")
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn test_decode_x11_color() {
-        let s = "0000/0000/0000";
-        assert_eq!((0, 0, 0), decode_x11_color(s).unwrap());
-
-        let s = "1111/2222/3333";
-        assert_eq!((0x1111, 0x2222, 0x3333), decode_x11_color(s).unwrap());
-
-        let s = "111/222/333";
-        assert_eq!((0x1110, 0x2220, 0x3330), decode_x11_color(s).unwrap());
-
-        let s = "11/22/33";
-        assert_eq!((0x1100, 0x2200, 0x3300), decode_x11_color(s).unwrap());
-
-        let s = "1/2/3";
-        assert_eq!((0x1000, 0x2000, 0x3000), decode_x11_color(s).unwrap());
-    }
-}