diff --git a/src/cluster_engine/engine.rs b/src/cluster_engine/engine.rs index 2b3ad34..adc5b33 100644 --- a/src/cluster_engine/engine.rs +++ b/src/cluster_engine/engine.rs @@ -39,6 +39,8 @@ impl Grouping { // - fix "Action". // - find a way to merge action, query and response in a type-safe manner... // - rename cluster_engine to model? +// - move the different operations in modules and just share the state +// - replace row_cache with the LRU crate I have open /// This signifies the action we're currently evaluating /// It is used for sending requests and receiving responses @@ -213,18 +215,14 @@ impl Engine { // Send the last action over the wire to be calculated fn update(&mut self, payload: (Query, Action)) -> Result<()> { - Ok(self.link.input_sender.send((payload.0, payload.1))?) + Ok(self.link.request(&payload.0, payload.1)?) } /// Fetch the channels to see if there're any updates pub fn process(&mut self) -> Result<()> { - let response = match self.link.output_receiver.try_recv() { - // We received something - Ok(Ok(response)) => response, - // We received nothing - Err(_) => return Ok(()), - // There was an error, we forward it - Ok(Err(e)) => return Err(e), + let response = match self.link.receive()? { + Some(n) => n, + None => return Ok(()), }; match response { @@ -269,43 +267,36 @@ impl Engine { .collect() } - pub fn request_contents(&mut self, range: &Range) -> Result<()> { - // Mark the rows as being loaded - for index in range.clone() { - if self.row_cache.cache_get(&index).is_none() { - self.row_cache.cache_set(index, LoadingState::Loading); - } - } - let request = self.make_normal_query(range.clone()); - self.link - .input_sender - .send((request.clone(), Action::Mails))?; - Ok(()) - } - - /// Query the contents for the current filter settings - /// This is a blocking call to simplify things a great deal - /// - returns the data, and an indicator that data is missing so that we can load more data - pub fn current_contents( - &mut self, - range: &Range, - ) -> Result<(Vec>, bool)> { + /// Query the contents for the current filter settings. + /// This call will return the available data and request additional data when it is missing. + /// The return value indicates whether a row is loaded or loading. + pub fn current_contents(&mut self, range: &Range) -> Result>> { // build an array with either empty values or values from our cache. let mut rows = Vec::new(); - let mut data_missing = false; + + let mut missing_data = false; for index in range.clone() { let entry = self.row_cache.cache_get(&index); let entry = match entry { Some(LoadingState::Loaded(n)) => Some((*n).clone()), Some(LoadingState::Loading) => None, None => { - data_missing = true; + // for simplicity, we keep the "something is missing" state separate + missing_data = true; + + // Mark the row as being loaded + self.row_cache.cache_set(index, LoadingState::Loading); None } }; rows.push(entry); } - Ok((rows, data_missing)) + // Only if at least some data is missing do we perform the request + if missing_data && !range.is_empty() { + let request = self.make_normal_query(range.clone()); + self.link.request(&request, Action::Mails)?; + } + Ok(rows) } pub fn is_busy(&self) -> bool { @@ -320,7 +311,7 @@ impl Engine { /// If we're loading mails pub fn is_mail_busy(&self) -> bool { - !self.link.input_sender.is_empty() + self.link.is_processing() } fn make_group_query(&self) -> Result { diff --git a/src/cluster_engine/link.rs b/src/cluster_engine/link.rs index 07d8e85..233e7ca 100644 --- a/src/cluster_engine/link.rs +++ b/src/cluster_engine/link.rs @@ -25,10 +25,6 @@ use super::partitions::{Partition, Partitions}; // - instead of hard-coding subject/sender-domain, have a "Detail" trait // - consider a better logic for the cache (by row id and just fetch the smallest range that contains all missing numbers) -pub trait Payload { - fn map_response(self, response: T) -> Self; -} - #[derive(Debug)] pub enum Response { Grouped(Query, Context, Partitions), @@ -43,6 +39,41 @@ pub struct Link { pub input_sender: InputSender, pub output_receiver: OutputReciever, pub handle: Handle, + // We need to account for the brief moment where the processing channel is empty + // but we're applying the results. If there is a UI update in this window, + // the UI will not update again after the changes were applied because an empty + // channel indicates completed processing. + // There's also a delay between a request taken out of the input channel and being + // put into the output channel. In order to account for all of this, we emploty a + // request counter to know how many requests are currently in the pipeline + request_counter: usize, +} + +impl Link { + pub fn request(&mut self, query: &Query, context: Context) -> Result<()> { + self.request_counter += 1; + self.input_sender.send((query.clone(), context))?; + Ok(()) + } + + pub fn receive(&mut self) -> Result>> { + match self.output_receiver.try_recv() { + // We received something + Ok(Ok(response)) => { + // Only subtract if we successfuly received a value + self.request_counter -= 1; + Ok(Some(response)) + } + // We received nothing + Err(_) => Ok(None), + // There was an error, we forward it + Ok(Err(e)) => Err(e), + } + } + + pub fn is_processing(&self) -> bool { + self.request_counter > 0 + } } pub fn run(config: &Config) -> Result> { @@ -54,6 +85,7 @@ pub fn run(config: &Config) -> Result( let response = match query { Query::Grouped { .. } => { let partitions = calculate_partitions(&result)?; - Response::Grouped(query, context, Partitions::new(partitions)) + Response::Grouped(query, context, partitions) } Query::Normal { .. } => { let converted = calculate_rows(&result)?; @@ -79,14 +111,14 @@ fn inner_loop( } } -fn calculate_partitions(result: &[QueryResult]) -> Result> { +fn calculate_partitions(result: &[QueryResult]) -> Result { let mut partitions = Vec::new(); for r in result.iter() { let partition = r.try_into()?; partitions.push(partition); } - Ok(partitions) + Ok(Partitions::new(partitions)) } fn calculate_rows(result: &[QueryResult]) -> Result> { diff --git a/src/gui/mail_panel.rs b/src/gui/mail_panel.rs index d78c7cd..402655d 100644 --- a/src/gui/mail_panel.rs +++ b/src/gui/mail_panel.rs @@ -26,16 +26,18 @@ impl<'a> Widget for MailPanel<'a> { &mut selected_row, self.engine.current_element_count(), |range| { - let (rows, load_more) = match self.engine.current_contents(&range) { - Ok((n, load_more)) => (n, load_more), + // we overshoot the range a bit, as otherwise somehow the bottom is always empty + let range = std::ops::Range { + start: range.start, + end: range.end + 6, + }; + let rows = match self.engine.current_contents(&range) { + Ok(n) => n, Err(e) => { *self.error = Some(e); - (empty_vec.clone(), false) + empty_vec.clone() } }; - if load_more { - *self.error = self.engine.request_contents(&range).err(); - } rows }, )