feat: add "new-topic" command and "new --topic" option

This makes it easier to have "topic pages" in a journal, for
collecting entries related to a certain topic. The topic page uses
ikiwiki's !inline directive to collect pages linking to it.

8 files changed, 118 insertions, 8 deletions

diff --git a/jt.md b/jt.md
index d1f3b14..958de77 100644
--- a/jt.md
+++ b/jt.md
@@ -247,6 +247,32 @@ and draft 0 in jrnl contains "custom new entry template"
 This is a custom new entry template.
 ~~~
 
+## Use topic pages
+
+Verify that we can create a new topic page and a new entry referring
+to that topic page.
+
+~~~scenario
+given an installed jt
+
+when I run jt2 --dirname jrnl init default "My test journal"
+then command is successful
+
+when I try to run jt2 --editor=none --dirname=jrnl new --topic foo "Abracadabra"
+then command fails
+then stderr contains "foo"
+
+when I run jt2 --editor=none --dirname=jrnl new-topic foo "Things about Foo"
+then command is successful
+then file jrnl/foo.mdwn contains "Things about Foo"
+
+when I run jt2 --editor=none --dirname=jrnl new --topic foo "Abracadabra"
+then command is successful
+and there is one draft in jrnl
+and draft 0 in jrnl links to "foo"
+~~~
+
+
 # Colophon
 
 This document is meant to be processed with the [Subplot][] program to
diff --git a/src/bin/jt2.rs b/src/bin/jt2.rs
index 25a3a13..677bb35 100644
--- a/src/bin/jt2.rs
+++ b/src/bin/jt2.rs
@@ -3,7 +3,7 @@ use jt2::error::JournalError;
 use jt2::journal::Journal;
 use jt2::opt::{Opt, SubCommand};
 
-use std::path::Path;
+use std::path::{Path, PathBuf};
 use structopt::StructOpt;
 
 fn main() -> anyhow::Result<()> {
@@ -17,7 +17,8 @@ fn main() -> anyhow::Result<()> {
             description,
         } => init(&config.dirname, &journalname, &description, &config)?,
         SubCommand::IsJournal => is_journal(&config)?,
-        SubCommand::New { title } => new_draft(&title, &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)?,
     }
@@ -41,9 +42,15 @@ fn is_journal(config: &Configuration) -> anyhow::Result<()> {
     Ok(())
 }
 
-fn new_draft(title: &str, config: &Configuration) -> anyhow::Result<()> {
+fn new_draft(title: &str, topic: &Option<PathBuf>, config: &Configuration) -> anyhow::Result<()> {
     let journal = Journal::new(&config.dirname, &config.entries)?;
-    journal.new_draft(title, &config.editor)?;
+    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(())
 }
 
diff --git a/src/error.rs b/src/error.rs
index a6f239e..89a10c1 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -34,14 +34,22 @@ pub enum JournalError {
     #[error("failed to create journal entry {0}: {1}")]
     WriteEntry(PathBuf, #[source] std::io::Error),
 
-    /// To many drafts.
-    #[error("there are already {0} drafts in {1}, can't create more")]
-    TooManyDrafts(usize, PathBuf),
+    /// Failed to write topic page.
+    #[error("failed to create topic page {0}: {1}")]
+    WriteTopic(PathBuf, #[source] std::io::Error),
 
     /// User chose a draft that doesn't exist.
     #[error("No draft {0} in {1}")]
     NoSuchDraft(String, PathBuf),
 
+    /// Too many drafts.
+    #[error("there are already {0} drafts in {1}, can't create more")]
+    TooManyDrafts(usize, PathBuf),
+
+    /// User chose a topic that doesn't exist.
+    #[error("No topic page {0}")]
+    NoSuchTopic(PathBuf),
+
     /// Failed to read draft.
     #[error("failed to drafts {0}: {1}")]
     ReadDraft(PathBuf, #[source] std::io::Error),
diff --git a/src/journal.rs b/src/journal.rs
index 788a34b..41e6d3d 100644
--- a/src/journal.rs
+++ b/src/journal.rs
@@ -57,7 +57,12 @@ impl Journal {
         self.entries.clone()
     }
 
-    pub fn new_draft(&self, title: &str, editor: &str) -> Result<(), JournalError> {
+    pub fn new_draft(
+        &self,
+        title: &str,
+        topic: &Option<PathBuf>,
+        editor: &str,
+    ) -> Result<(), JournalError> {
         let drafts = self.drafts();
         if !drafts.exists() {
             std::fs::create_dir(&drafts)
@@ -67,6 +72,13 @@ impl Journal {
         let mut context = Context::new();
         context.insert("title", title);
         context.insert("date", &current_timestamp());
+        if let Some(ref topic) = topic {
+            let pathname = topic_path(self.dirname(), topic);
+            if !pathname.exists() {
+                return Err(JournalError::NoSuchTopic(topic.to_path_buf()));
+            }
+            context.insert("topic", &topic.display().to_string());
+        }
 
         let pathname = self.pick_file_id(&drafts)?;
         let text = self.templates.new_draft(&context)?;
@@ -143,6 +155,18 @@ impl Journal {
         })?;
         Ok(())
     }
+
+    pub fn new_topic(&self, path: &Path, title: &str, editor: &str) -> Result<(), JournalError> {
+        let mut context = Context::new();
+        context.insert("title", title);
+
+        let pathname = topic_path(self.dirname(), path);
+        let text = self.templates.new_topic(&context)?;
+        std::fs::write(&pathname, text)
+            .map_err(|err| JournalError::WriteTopic(pathname.to_path_buf(), err))?;
+        self.edit(editor, &pathname)?;
+        Ok(())
+    }
 }
 
 fn is_dir(path: &Path) -> bool {
@@ -153,6 +177,12 @@ fn is_dir(path: &Path) -> bool {
     }
 }
 
+fn topic_path(dirname: &Path, topic: &Path) -> PathBuf {
+    let mut path = dirname.join(topic);
+    path.set_extension("mdwn");
+    path
+}
+
 fn current_timestamp() -> String {
     let now = Local::now();
     let now: DateTime<Local> = DateTime::from(now);
diff --git a/src/opt.rs b/src/opt.rs
index 5455777..4e6f46d 100644
--- a/src/opt.rs
+++ b/src/opt.rs
@@ -64,6 +64,18 @@ pub enum SubCommand {
     New {
         #[structopt(help = "Title of new draft")]
         title: String,
+
+        #[structopt(long, help = "Add link to a topic page")]
+        topic: Option<PathBuf>,
+    },
+
+    /// Create topic page.
+    NewTopic {
+        #[structopt(help = "Path to topic page in journal")]
+        path: PathBuf,
+
+        #[structopt(help = "Title of topic page")]
+        title: String,
     },
 
     /// Invoke editor on journal entry draft.
diff --git a/src/template.rs b/src/template.rs
index 89c1a15..23b9b06 100644
--- a/src/template.rs
+++ b/src/template.rs
@@ -4,10 +4,22 @@ use tera::{Context, Tera};
 
 const NEW_ENTRY: &str = r#"[[!meta title="{{ title }}"]]
 [[!meta date="{{ date }}"]]
+{% if topic %}
+[[!meta link="{{ topic }}"]]
+{% endif %}
 
 This is the default template.
 "#;
 
+const NEW_TOPIC: &str = r#"[[!meta title="{{ title }}"]]
+
+This is the default topic template.
+
+# Entries
+
+[[!inline pages="link(.)" archive=yes reverse=yes trail=yes]]
+"#;
+
 pub struct Templates {
     tera: Tera,
 }
@@ -17,6 +29,7 @@ impl Templates {
         let glob = format!("{}/.config/templates/*", dirname.display());
         let mut tera = Tera::new(&glob).expect("Tera::new");
         add_default_template(&mut tera, "new_entry", NEW_ENTRY);
+        add_default_template(&mut tera, "new_topic", NEW_TOPIC);
         Ok(Self { tera })
     }
 
@@ -24,6 +37,10 @@ impl Templates {
         self.render("new_entry", &context)
     }
 
+    pub fn new_topic(&self, context: &Context) -> Result<String, JournalError> {
+        self.render("new_topic", &context)
+    }
+
     fn render(&self, name: &str, context: &Context) -> Result<String, JournalError> {
         match self.tera.render(name, &context) {
             Ok(s) => Ok(s),
diff --git a/subplot/jt.py b/subplot/jt.py
index 6ce75b0..d6023b3 100644
--- a/subplot/jt.py
+++ b/subplot/jt.py
@@ -135,6 +135,13 @@ def draft_contains_string(ctx, dirname=None, draftno=None, pattern=None):
         assert pattern in data
 
 
+def draft_links_to_topic(ctx, dirname=None, draftno=None, topic=None):
+    logging.debug(f"checking draft {draftno} in {dirname} links to {topic!r}")
+    draft_contains_string(
+        ctx, dirname=dirname, draftno=draftno, pattern=f'\n[[!meta link="{topic}"]]\n'
+    )
+
+
 def edit_draft(ctx, dirname=None, draftno=None, text=None):
     logging.debug(f"editing draft {draftno} in {dirname} to also contain {text!r}")
     draft = os.path.join(dirname, "drafts", f"{draftno}.md")
diff --git a/subplot/jt.yaml b/subplot/jt.yaml
index 65bf90e..a3d4f0f 100644
--- a/subplot/jt.yaml
+++ b/subplot/jt.yaml
@@ -43,6 +43,9 @@
 - then: draft {draftno} in {dirname} contains "{pattern:text}"
   function: draft_contains_string
 
+- then: draft {draftno} in {dirname} links to "{topic}"
+  function: draft_links_to_topic
+
 - then: there are no journal entries in {dirname}
   function: journal_has_no_entries