ad khcursor prev

3 files changed, 44 insertions, 1 deletions

diff --git a/src/actions/cursor.rs b/src/actions/cursor.rs
index 4fc6a92..40f895a 100644
--- a/src/actions/cursor.rs
+++ b/src/actions/cursor.rs
@@ -3,12 +3,17 @@ extern crate atty;
 use cursorfile;
 use utils::stdioutils;
 use KhResult;
+use khline::KhLine;
+use seqfile;
 
-pub fn do_cursor(_args: &[&str]) -> KhResult<()> {
+pub fn do_cursor(args: &[&str]) -> KhResult<()> {
   if !stdioutils::is_stdin_tty() {
     write_stdin_to_cursorfile()?;
   } else {
     //println!("stdin is tty")
+    if args.len() > 0 && args[0] == "prev" {
+      return cursor_sequence_prev();
+    }
   }
 
   if !stdioutils::is_stdout_tty() || stdioutils::is_stdin_tty() {
@@ -36,6 +41,19 @@ fn write_cursorfile_to_stdout() {
   }
 }
 
+fn cursor_sequence_prev() -> KhResult<()> {
+  let cursor_event = cursorfile::read_cursorfile()?.to_event().unwrap();
+  let mut seq = seqfile::read_seqfile_backwards()?
+    .map(|line| line.parse::<KhLine>().unwrap());
+  seq.find(|line| line.matches(&cursor_event));
+  if let Some(next_elem) = seq.next() {
+    cursorfile::write_cursorfile(&next_elem.to_string())?;
+  } else {
+    warn!("Already at end of sequence");
+  }
+  Ok(())
+}
+
 #[cfg(test)]
 mod integration {
   use super::*;
diff --git a/src/seqfile.rs b/src/seqfile.rs
index 66caed3..9a368f1 100644
--- a/src/seqfile.rs
+++ b/src/seqfile.rs
@@ -21,6 +21,12 @@ pub fn read_seqfile() -> io::Result<impl Iterator<Item = String>> {
   fileutil::read_lines_from_file(&seqfile)
 }
 
+pub fn read_seqfile_backwards() -> io::Result<impl Iterator<Item = String>> {
+  let seqfile = get_seqfile();
+  debug!("Reading sequence file: {}", seqfile.to_string_lossy());
+  fileutil::read_lines_from_file_backwards(&seqfile)
+}
+
 #[cfg(test)]
 mod tests {
   use super::*;
@@ -41,6 +47,18 @@ mod tests {
   }
 
   #[test]
+  fn read_seqfile_backwards_test() {
+    let testdir = prepare_testdir("testdir_with_seq");
+    let mut seqfile_read: Vec<String> = read_seqfile_backwards().unwrap().collect();
+    seqfile_read.reverse();
+    let mut seqfile_string = seqfile_read.join("\n");
+    seqfile_string.push('\n');
+
+    let predicate = predicate::str::similar(seqfile_string);
+    testdir.child(".khaleesi/seq").assert(predicate);
+  }
+
+  #[test]
   fn write_to_seqfile_test() {
     let testdir = prepare_testdir("testdir");
     let teststr = "Teststr äöüß\n";
diff --git a/src/utils/fileutil.rs b/src/utils/fileutil.rs
index ab90a55..3c577e7 100644
--- a/src/utils/fileutil.rs
+++ b/src/utils/fileutil.rs
@@ -53,6 +53,13 @@ pub fn read_lines_from_file(filepath: &Path) -> io::Result<impl Iterator<Item =
   lines.map(|result| result.into_iter())
 }
 
+pub fn read_lines_from_file_backwards(filepath: &Path) -> io::Result<impl Iterator<Item = String>> {
+  let f = fs::File::open(filepath)?;
+  let f = BufReader::new(f);
+  let lines: Result<Vec<String>, io::Error> = f.lines().collect();
+  lines.map(|result| result.into_iter().rev())
+}
+
 pub fn read_file_to_string(path: &Path) -> io::Result<String> {
   let mut file = fs::File::open(&path)?;
   let mut contents = String::new();