refactor: move subcommand implementations into src/cmd.rs

The command line interface definition (for structopt) and
implementation are now both in src/cmd.rs. This seems tidier than
having them split between src/opt.rs and src/bin/jt2.rs.

4 files changed, 126 insertions, 90 deletions

diff --git a/src/bin/jt2.rs b/src/bin/jt2.rs
index 677bb35..8ef0728 100644
--- a/src/bin/jt2.rs
+++ b/src/bin/jt2.rs
@@ -1,9 +1,6 @@
 use jt2::config::Configuration;
-use jt2::error::JournalError;
-use jt2::journal::Journal;
 use jt2::opt::{Opt, SubCommand};
 
-use std::path::{Path, PathBuf};
 use structopt::StructOpt;
 
 fn main() -> anyhow::Result<()> {
@@ -11,59 +8,13 @@ fn main() -> anyhow::Result<()> {
     let opt = Opt::from_args();
     let config = Configuration::read(&opt)?;
     match opt.cmd {
-        SubCommand::Config => config.dump(),
-        SubCommand::Init {
-            journalname,
-            description,
-        } => init(&config.dirname, &journalname, &description, &config)?,
-        SubCommand::IsJournal => is_journal(&config)?,
-        SubCommand::New { title, topic } => new_draft(&title, &topic, &config)?,
-        SubCommand::NewTopic { path, title } => new_topic(&path, &title, &config)?,
-        SubCommand::Edit { draft } => edit_draft(&draft, &config)?,
-        SubCommand::Finish { draft, basename } => finish_draft(&draft, &basename, &config)?,
+        SubCommand::Config(x) => x.run(&config)?,
+        SubCommand::Init(x) => x.run(&config)?,
+        SubCommand::IsJournal(x) => x.run(&config)?,
+        SubCommand::New(x) => x.run(&config)?,
+        SubCommand::NewTopic(x) => x.run(&config)?,
+        SubCommand::Edit(x) => x.run(&config)?,
+        SubCommand::Finish(x) => x.run(&config)?,
     }
     Ok(())
 }
-
-fn init(
-    dirname: &Path,
-    _journalname: &str,
-    _description: &str,
-    config: &Configuration,
-) -> anyhow::Result<()> {
-    Journal::init(dirname, &config.entries)?;
-    Ok(())
-}
-
-fn is_journal(config: &Configuration) -> anyhow::Result<()> {
-    if !Journal::is_journal(&config.dirname, &config.entries) {
-        return Err(JournalError::NotAJournal(config.dirname.display().to_string()).into());
-    }
-    Ok(())
-}
-
-fn new_draft(title: &str, topic: &Option<PathBuf>, config: &Configuration) -> anyhow::Result<()> {
-    let journal = Journal::new(&config.dirname, &config.entries)?;
-    journal.new_draft(title, topic, &config.editor)?;
-    Ok(())
-}
-
-fn new_topic(path: &Path, title: &str, config: &Configuration) -> anyhow::Result<()> {
-    let journal = Journal::new(&config.dirname, &config.entries)?;
-    journal.new_topic(path, title, &config.editor)?;
-    Ok(())
-}
-
-fn edit_draft(draft: &str, config: &Configuration) -> anyhow::Result<()> {
-    let journal = Journal::new(&config.dirname, &config.entries)?;
-    let filename = journal.pick_draft(draft)?;
-    journal.edit_draft(&config.editor, &filename)?;
-    Ok(())
-}
-
-fn finish_draft(draft: &str, basename: &str, config: &Configuration) -> anyhow::Result<()> {
-    let journal = Journal::new(&config.dirname, &config.entries)?;
-    let filename = journal.pick_draft(draft)?;
-    journal.finish_draft(&filename, basename)?;
-    Ok(())
-}
diff --git a/src/cmd.rs b/src/cmd.rs
new file mode 100644
index 0000000..c1606e0
--- /dev/null
+++ b/src/cmd.rs
@@ -0,0 +1,110 @@
+use crate::config::Configuration;
+use crate::error::JournalError;
+use crate::journal::Journal;
+use std::path::PathBuf;
+use structopt::StructOpt;
+
+#[derive(Debug, StructOpt)]
+pub struct Config {}
+
+impl Config {
+    pub fn run(&self, config: &Configuration) -> Result<(), JournalError> {
+        config.dump();
+        Ok(())
+    }
+}
+
+#[derive(Debug, StructOpt)]
+pub struct Init {
+    #[structopt(help = "Short name for journal")]
+    journalname: String,
+
+    #[structopt(help = "Short description of journal, its title")]
+    description: String,
+}
+
+impl Init {
+    pub fn run(&self, config: &Configuration) -> Result<(), JournalError> {
+        Journal::init(&config.dirname, &config.entries)?;
+        Ok(())
+    }
+}
+
+#[derive(Debug, StructOpt)]
+pub struct IsJournal {}
+
+impl IsJournal {
+    pub fn run(&self, config: &Configuration) -> Result<(), JournalError> {
+        if !Journal::is_journal(&config.dirname, &config.entries) {
+            return Err(JournalError::NotAJournal(config.dirname.display().to_string()).into());
+        }
+        Ok(())
+    }
+}
+
+#[derive(Debug, StructOpt)]
+pub struct New {
+    #[structopt(help = "Title of new draft")]
+    title: String,
+
+    #[structopt(long, help = "Add link to a topic page")]
+    topic: Option<PathBuf>,
+}
+
+impl New {
+    pub fn run(&self, config: &Configuration) -> Result<(), JournalError> {
+        let journal = Journal::new(&config.dirname, &config.entries)?;
+        journal.new_draft(&self.title, &self.topic, &config.editor)?;
+        Ok(())
+    }
+}
+
+#[derive(Debug, StructOpt)]
+pub struct NewTopic {
+    #[structopt(help = "Path to topic page in journal")]
+    path: PathBuf,
+
+    #[structopt(help = "Title of topic page")]
+    title: String,
+}
+
+impl NewTopic {
+    pub fn run(&self, config: &Configuration) -> Result<(), JournalError> {
+        let journal = Journal::new(&config.dirname, &config.entries)?;
+        journal.new_topic(&self.path, &self.title, &config.editor)?;
+        Ok(())
+    }
+}
+
+#[derive(Debug, StructOpt)]
+pub struct Edit {
+    /// Draft id.
+    draft: String,
+}
+
+impl Edit {
+    pub fn run(&self, config: &Configuration) -> Result<(), JournalError> {
+        let journal = Journal::new(&config.dirname, &config.entries)?;
+        let filename = journal.pick_draft(&self.draft)?;
+        journal.edit_draft(&config.editor, &filename)?;
+        Ok(())
+    }
+}
+
+#[derive(Debug, StructOpt)]
+pub struct Finish {
+    /// Draft id.
+    draft: String,
+
+    /// Set base name of published file.
+    basename: String,
+}
+
+impl Finish {
+    pub fn run(&self, config: &Configuration) -> Result<(), JournalError> {
+        let journal = Journal::new(&config.dirname, &config.entries)?;
+        let filename = journal.pick_draft(&self.draft)?;
+        journal.finish_draft(&filename, &self.basename)?;
+        Ok(())
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
index d9b0801..a634111 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,3 +1,4 @@
+pub mod cmd;
 pub mod config;
 pub mod error;
 pub mod journal;
diff --git a/src/opt.rs b/src/opt.rs
index 4e6f46d..7d3dcda 100644
--- a/src/opt.rs
+++ b/src/opt.rs
@@ -1,5 +1,6 @@
 //! Command line options.
 
+use crate::cmd;
 use std::path::PathBuf;
 use structopt::StructOpt;
 
@@ -46,50 +47,23 @@ pub struct GlobalOptions {
 #[derive(Debug, StructOpt)]
 pub enum SubCommand {
     /// Show configuration.
-    Config,
+    Config(cmd::Config),
 
     /// Create a new journal in the chosen directory.
-    Init {
-        #[structopt(help = "Short name for journal")]
-        journalname: String,
-
-        #[structopt(help = "Short description of journal, its title")]
-        description: String,
-    },
+    Init(cmd::Init),
 
     /// Check if a directory is a journal.
-    IsJournal,
+    IsJournal(cmd::IsJournal),
 
     /// Create draft for a new journal entry.
-    New {
-        #[structopt(help = "Title of new draft")]
-        title: String,
-
-        #[structopt(long, help = "Add link to a topic page")]
-        topic: Option<PathBuf>,
-    },
+    New(cmd::New),
 
     /// Create topic page.
-    NewTopic {
-        #[structopt(help = "Path to topic page in journal")]
-        path: PathBuf,
-
-        #[structopt(help = "Title of topic page")]
-        title: String,
-    },
+    NewTopic(cmd::NewTopic),
 
     /// Invoke editor on journal entry draft.
-    Edit {
-        /// Draft id.
-        draft: String,
-    },
+    Edit(cmd::Edit),
 
     /// Finish a journal entry draft.
-    Finish {
-        /// Draft id.
-        draft: String,
-
-        /// Set base name of published file.
-        basename: String,
-    },
+    Finish(cmd::Finish),
 }