--encoding cli flag

doc/phetch.1.md

@@ -63,6 +63,9 @@ If no URL is given, however, *phetch* will launch and open its default
 *-C*, *--no-config*
 	Do not use any config file.
 
+*-e*, *--encoding* _ENCODING_
+	Render text views in CP437 or UTF8 (default) encoding.
+
 *-h*, *--help*
 	Print a help summary and exit.
 

src/args.rs

@@ -1,11 +1,14 @@
 //! args::parse() is used to parse command line arguments into a
 //! Config structure.
 
-use crate::{
-    config::{self, Config},
-    ui::Mode,
+use {
+    crate::{
+        config::{self, Config},
+        encoding::Encoding,
+        ui::Mode,
+    },
+    std::{error::Error, fmt, result::Result},
 };
-use std::{error::Error, fmt, result::Result};
 
 /// The error returned if something goes awry while parsing the
 /// command line arguments.
@@ -182,6 +185,14 @@ pub fn parse<T: AsRef<str>>(args: &[T]) -> Result<Config, ArgError> {
                 set_nomedia = true;
                 cfg.media = None;
             }
+            "-e" | "--encoding" | "-encoding" => {
+                if let Some(encoding) = iter.next() {
+                    cfg.encoding = Encoding::from_str(encoding.as_ref())
+                        .map_err(|e| ArgError::new(e.to_string()))?;
+                } else {
+                    return Err(ArgError::new("--encoding expects an ENCODING arg"));
+                }
+            }
             arg => {
                 if arg.starts_with('-') {
                     return Err(ArgError::new(format!("unknown flag: {}", arg)));

src/encoding.rs

@@ -1,5 +1,7 @@
+use std::io::Result;
+
 /// Encoding of Gopher response. Only UTF8 and CP437 are supported.
-#[derive(Copy, Clone)]
+#[derive(Debug, PartialEq, Copy, Clone)]
 pub enum Encoding {
     /// Unicode
     UTF8,
@@ -12,3 +14,17 @@ impl Default for Encoding {
         Encoding::UTF8
     }
 }
+
+impl Encoding {
+    /// Accepts a string like "UTF8" or "CP437" and returns the
+    /// appropriate `Encoding`, or an `Err`.
+    pub fn from_str(s: &str) -> Result<Self> {
+        match s.to_lowercase().as_ref() {
+            "utf8" | "utf-8" | "utf 8" => Ok(Encoding::UTF8),
+            "cp437" | "cp-437" | "cp 437" | "pc8" | "pc-8" | "oem us" | "oem-us" => {
+                Ok(Encoding::CP437)
+            }
+            _ => Err(error!("Expected CP437 or UTF8 encoding")),
+        }
+    }
+}