Text change generation, RPC call handling.

3 files changed, 163 insertions, 38 deletions

diff --git a/helix-lsp/src/client.rs b/helix-lsp/src/client.rs
index 56413768..3c2c1ce0 100644
--- a/helix-lsp/src/client.rs
+++ b/helix-lsp/src/client.rs
@@ -1,11 +1,11 @@
 use crate::{
     transport::{Payload, Transport},
-    Error, Notification,
+    Call, Error,
 };
 
 type Result<T> = core::result::Result<T, Error>;
 
-use helix_core::{State, Transaction};
+use helix_core::{ChangeSet, Transaction};
 use helix_view::Document;
 
 // use std::collections::HashMap;
@@ -27,7 +27,7 @@ pub struct Client {
     stderr: BufReader<ChildStderr>,
 
     outgoing: Sender<Payload>,
-    pub incoming: Receiver<Notification>,
+    pub incoming: Receiver<Call>,
 
     pub request_counter: u64,
 
@@ -87,6 +87,7 @@ impl Client {
         Ok(params)
     }
 
+    /// Execute a RPC request on the language server.
     pub async fn request<R: lsp::request::Request>(
         &mut self,
         params: R::Params,
@@ -126,6 +127,7 @@ impl Client {
         Ok(response)
     }
 
+    /// Send a RPC notification to the language server.
     pub async fn notify<R: lsp::notification::Notification>(
         &mut self,
         params: R::Params,
@@ -149,6 +151,35 @@ impl Client {
         Ok(())
     }
 
+    /// Reply to a language server RPC call.
+    pub async fn reply(
+        &mut self,
+        id: jsonrpc::Id,
+        result: core::result::Result<Value, jsonrpc::Error>,
+    ) -> Result<()> {
+        use jsonrpc::{Failure, Output, Success, Version};
+
+        let output = match result {
+            Ok(result) => Output::Success(Success {
+                jsonrpc: Some(Version::V2),
+                id,
+                result,
+            }),
+            Err(error) => Output::Failure(Failure {
+                jsonrpc: Some(Version::V2),
+                id,
+                error,
+            }),
+        };
+
+        self.outgoing
+            .send(Payload::Response(output))
+            .await
+            .map_err(|e| Error::Other(e.into()))?;
+
+        Ok(())
+    }
+
     // -------------------------------------------------------------------------------------------
     // General messages
     // -------------------------------------------------------------------------------------------
@@ -163,7 +194,9 @@ impl Client {
             // root_uri: Some(lsp_types::Url::parse("file://localhost/")?),
             root_uri: None, // set to project root in the future
             initialization_options: None,
-            capabilities: lsp::ClientCapabilities::default(),
+            capabilities: lsp::ClientCapabilities {
+                ..Default::default()
+            },
             trace: None,
             workspace_folders: None,
             client_info: None,
@@ -203,23 +236,107 @@ impl Client {
         .await
     }
 
+    fn to_changes(changeset: &ChangeSet) -> Vec<lsp::TextDocumentContentChangeEvent> {
+        let mut iter = changeset.changes().iter().peekable();
+        let mut old_pos = 0;
+
+        let mut changes = Vec::new();
+
+        use crate::util::pos_to_lsp_pos;
+        use helix_core::Operation::*;
+
+        // TEMP
+        let rope = helix_core::Rope::from("");
+        let old_text = rope.slice(..);
+
+        while let Some(change) = iter.next() {
+            let len = match change {
+                Delete(i) | Retain(i) => *i,
+                Insert(_) => 0,
+            };
+            let old_end = old_pos + len;
+
+            match change {
+                Retain(_) => {}
+                Delete(_) => {
+                    let start = pos_to_lsp_pos(&old_text, old_pos);
+                    let end = pos_to_lsp_pos(&old_text, old_end);
+
+                    // a subsequent ins means a replace, consume it
+                    if let Some(Insert(s)) = iter.peek() {
+                        iter.next();
+
+                        // replacement
+                        changes.push(lsp::TextDocumentContentChangeEvent {
+                            range: Some(lsp::Range::new(start, end)),
+                            text: s.into(),
+                            range_length: None,
+                        });
+                    } else {
+                        // deletion
+                        changes.push(lsp::TextDocumentContentChangeEvent {
+                            range: Some(lsp::Range::new(start, end)),
+                            text: "".to_string(),
+                            range_length: None,
+                        });
+                    };
+                }
+                Insert(s) => {
+                    let start = pos_to_lsp_pos(&old_text, old_pos);
+
+                    // insert
+                    changes.push(lsp::TextDocumentContentChangeEvent {
+                        range: Some(lsp::Range::new(start, start)),
+                        text: s.into(),
+                        range_length: None,
+                    });
+                }
+            }
+            old_pos = old_end;
+        }
+
+        changes
+    }
+
     // TODO: trigger any time history.commit_revision happens
     pub async fn text_document_did_change(
         &mut self,
         doc: &Document,
         transaction: &Transaction,
     ) -> Result<()> {
+        // figure out what kind of sync the server supports
+
+        let capabilities = self.capabilities.as_ref().unwrap(); // TODO: needs post init
+
+        let sync_capabilities = match capabilities.text_document_sync {
+            Some(lsp::TextDocumentSyncCapability::Kind(kind)) => kind,
+            Some(lsp::TextDocumentSyncCapability::Options(lsp::TextDocumentSyncOptions {
+                change: Some(kind),
+                ..
+            })) => kind,
+            // None | SyncOptions { changes: None }
+            _ => return Ok(()),
+        };
+
+        let changes = match sync_capabilities {
+            lsp::TextDocumentSyncKind::Full => {
+                vec![lsp::TextDocumentContentChangeEvent {
+                    // range = None -> whole document
+                    range: None,        //Some(Range)
+                    range_length: None, // u64 apparently deprecated
+                    text: "".to_string(),
+                }] // TODO: probably need old_state here too?
+            }
+            lsp::TextDocumentSyncKind::Incremental => Self::to_changes(transaction.changes()),
+            lsp::TextDocumentSyncKind::None => return Ok(()),
+        };
+
         self.notify::<lsp::notification::DidChangeTextDocument>(lsp::DidChangeTextDocumentParams {
             text_document: lsp::VersionedTextDocumentIdentifier::new(
                 lsp::Url::from_file_path(doc.path().unwrap()).unwrap(),
                 doc.version,
             ),
-            content_changes: vec![lsp::TextDocumentContentChangeEvent {
-                // range = None -> whole document
-                range: None,        //Some(Range)
-                range_length: None, // u64 apparently deprecated
-                text: "".to_string(),
-            }], // TODO: probably need old_state here too?
+            content_changes: changes,
         })
         .await
     }
diff --git a/helix-lsp/src/lib.rs b/helix-lsp/src/lib.rs
index c37222f1..1ee8199f 100644
--- a/helix-lsp/src/lib.rs
+++ b/helix-lsp/src/lib.rs
@@ -1,13 +1,12 @@
 mod client;
 mod transport;
 
-use jsonrpc_core as jsonrpc;
-use lsp_types as lsp;
+pub use jsonrpc_core as jsonrpc;
+pub use lsp_types as lsp;
 
 pub use client::Client;
 pub use lsp::{Position, Url};
 
-use serde::{Deserialize, Serialize};
 use thiserror::Error;
 
 #[derive(Error, Debug)]
@@ -30,19 +29,13 @@ pub mod util {
         let line_start = doc.char_to_utf16_cu(line);
         doc.utf16_cu_to_char(pos.character as usize + line_start)
     }
-}
+    pub fn pos_to_lsp_pos(doc: &helix_core::RopeSlice, pos: usize) -> lsp::Position {
+        let line = doc.char_to_line(pos);
+        let line_start = doc.char_to_utf16_cu(line);
+        let col = doc.char_to_utf16_cu(pos) - line_start;
 
-/// A type representing all possible values sent from the server to the client.
-#[derive(Debug, PartialEq, Clone, Deserialize, Serialize)]
-#[serde(deny_unknown_fields)]
-#[serde(untagged)]
-enum Message {
-    /// A regular JSON-RPC request output (single response).
-    Output(jsonrpc::Output),
-    /// A notification.
-    Notification(jsonrpc::Notification),
-    /// A JSON-RPC request
-    Call(jsonrpc::Call),
+        lsp::Position::new(line as u64, col as u64)
+    }
 }
 
 #[derive(Debug, PartialEq, Clone)]
@@ -67,3 +60,5 @@ impl Notification {
         }
     }
 }
+
+pub use jsonrpc::Call;
diff --git a/helix-lsp/src/transport.rs b/helix-lsp/src/transport.rs
index 4ab3d5ec..4c349a13 100644
--- a/helix-lsp/src/transport.rs
+++ b/helix-lsp/src/transport.rs
@@ -2,7 +2,7 @@ use std::collections::HashMap;
 
 use log::debug;
 
-use crate::{Error, Message, Notification};
+use crate::{Error, Notification};
 
 type Result<T> = core::result::Result<T, Error>;
 
@@ -24,10 +24,23 @@ pub(crate) enum Payload {
         value: jsonrpc::MethodCall,
     },
     Notification(jsonrpc::Notification),
+    Response(jsonrpc::Output),
+}
+
+use serde::{Deserialize, Serialize};
+/// A type representing all possible values sent from the server to the client.
+#[derive(Debug, PartialEq, Clone, Deserialize, Serialize)]
+#[serde(deny_unknown_fields)]
+#[serde(untagged)]
+enum Message {
+    /// A regular JSON-RPC request output (single response).
+    Output(jsonrpc::Output),
+    /// A JSON-RPC request or notification.
+    Call(jsonrpc::Call),
 }
 
 pub(crate) struct Transport {
-    incoming: Sender<Notification>, // TODO Notification | Call
+    incoming: Sender<jsonrpc::Call>,
     outgoing: Receiver<Payload>,
 
     pending_requests: HashMap<jsonrpc::Id, Sender<Result<Value>>>,
@@ -42,7 +55,7 @@ impl Transport {
         ex: &Executor,
         reader: BufReader<ChildStdout>,
         writer: BufWriter<ChildStdin>,
-    ) -> (Receiver<Notification>, Sender<Payload>) {
+    ) -> (Receiver<jsonrpc::Call>, Sender<Payload>) {
         let (incoming, rx) = smol::channel::unbounded();
         let (tx, outgoing) = smol::channel::unbounded();
 
@@ -112,6 +125,10 @@ impl Transport {
                 let json = serde_json::to_string(&value)?;
                 self.send(json).await
             }
+            Payload::Response(error) => {
+                let json = serde_json::to_string(&error)?;
+                self.send(json).await
+            }
         }
     }
 
@@ -131,24 +148,18 @@ impl Transport {
         Ok(())
     }
 
-    pub async fn recv_msg(&mut self, msg: Message) -> anyhow::Result<()> {
+    async fn recv_msg(&mut self, msg: Message) -> anyhow::Result<()> {
         match msg {
             Message::Output(output) => self.recv_response(output).await?,
-            Message::Notification(jsonrpc::Notification { method, params, .. }) => {
-                let notification = Notification::parse(&method, params);
-
-                debug!("<- {} {:?}", method, notification);
-                self.incoming.send(notification).await?;
-            }
             Message::Call(call) => {
-                debug!("<- {:?}", call);
-                // dispatch
+                self.incoming.send(call).await?;
+                // let notification = Notification::parse(&method, params);
             }
         };
         Ok(())
     }
 
-    pub async fn recv_response(&mut self, output: jsonrpc::Output) -> anyhow::Result<()> {
+    async fn recv_response(&mut self, output: jsonrpc::Output) -> anyhow::Result<()> {
         match output {
             jsonrpc::Output::Success(jsonrpc::Success { id, result, .. }) => {
                 debug!("<- {}", result);
@@ -191,6 +202,8 @@ impl Transport {
                     }
                     let msg = msg.unwrap();
 
+                    debug!("<- {:?}", msg);
+
                     self.recv_msg(msg).await.unwrap();
                 }
             }