Gets all the window titles using AppleScript

macOS_window_titles.rs

use std::process::Command;

const PREFIX: &str = r#"tell application "System Events""#;
const SUFFIX: &str = r#"to get the title of every window of every process"#;
const PERMISSION_ERROR: &str = "osascript is not allowed assistive access";

#[derive(Debug, Copy, Clone)]
pub enum WindowTitleError {
	NoAccessibilityPermission,
}

pub fn window_titles() -> Result<Vec<String>, WindowTitleError> {
	let arguments = &["-ss", "-e", &format!("{} {}", PREFIX, SUFFIX)];
	let command = Command::new("osascript").args(arguments).output()
		.expect("failed to execute AppleScript command");

	let error = String::from_utf8_lossy(&command.stderr);
	match error.contains(PERMISSION_ERROR) {
		true => Err(WindowTitleError::NoAccessibilityPermission),
		false => Ok(split(&String::from_utf8_lossy(&command.stdout))),
	}
}

fn split(mut string: &str) -> Vec<String> {
	let mut titles = Vec::new();
	while let Some(start) = string.find('"') {
		let end = string[start + 1..].find('"').unwrap();
		titles.push(string[start + 1..][..end].to_string());
		string = &string[start + 1..][end + 1..];
	}
	titles
}

#[cfg(test)]
mod tests {
	use super::*;

	#[test]
	fn test_split() {
		let string = r#"{{}, {"0"}, {"1", "2"}}"#;
		assert_eq!(split(string), &["0", "1", "2"]);
	}
}