refactor(lsp): restructure lsp plugin controller architecture and simplify provider cache

- Replace LSPManager usage with LSPController integration
- Move UI access through lsp_controller.lsp_manager_ui
- Remove legacy ProviderResponseCache client management
- Simplify completion filtering and matcher handling
- Improve typing annotations and modernize union syntax
- Clean up unused imports and dead code
- Fix completion item parsing for insertText/textEdit fallbacks
- Add async-safe scrolling via GLib.idle_add

plugins/code/ui/lsp_manager/handlers/__init__.py

@@ -0,0 +1,5 @@
+from .base import BaseHandler
+from .default import DefaultHandler
+from .python import PythonHandler
+from .java import JavaHandler
+from .registry import HandlerRegistry

plugins/code/ui/lsp_manager/handlers/base.py

@@ -0,0 +1,31 @@
+# Python imports
+from abc import ABC
+
+# Lib imports
+
+# Application imports
+
+
+
+class BaseHandler:
+    def __init__(self):
+        self.context        = None
+        self.response_cache = None
+
+
+    def set_context(self, context):
+        self.context = context
+
+    def set_response_cache(self, response_cache):
+        self.response_cache = response_cache
+
+    @property
+    def emit(self):
+        return self.context.emit
+
+    @property
+    def emit_to(self):
+        return self.context.emit_to
+
+    def handle(self, method: str, response, controller):
+        pass

plugins/code/ui/lsp_manager/handlers/default.py

@@ -0,0 +1,100 @@
+# Python imports
+
+# Lib imports
+
+# Application imports
+from libs.event_factory import Event_Factory, Code_Event_Types
+
+from .base import BaseHandler
+
+
+
+class DefaultHandler(BaseHandler):
+    """Fallback handler for unknown languages - uses generic LSP handling."""
+
+    def handle(self, method: str, response, controller):
+        match method:
+            case "textDocument/completion":
+                self._handle_completion(response)
+            case "textDocument/definition":
+                self._handle_definition(response, controller)
+            case "textDocument/publishDiagnostics":
+                self._handle_diagnostics(response)
+
+    def _handle_completion(self, result):
+        if not result: return
+
+        items = result.get("items", []) if isinstance(result, dict) else result
+
+        self.response_cache.matchers.clear()
+        for item in items:
+            label = item.get("label")
+            if not label:
+                continue
+
+            text = (
+                item.get("insertText")
+                or item.get("textEdit", {}).get("newText")
+                or item.get("textEditText", "")
+                or label
+            )
+
+            detail = item.get("detail")
+            doc    = item.get("documentation")
+
+            if detail:
+                info = detail
+            elif isinstance(doc, dict):
+                info = doc.get("value", "")
+            else:
+                info = str(doc) if doc else ""
+
+            self.response_cache.matchers[label] = {
+                "label": label,
+                "text": text,
+                "info": info,
+            }
+
+        self.context._prompt_completion_request()
+
+    def _handle_definition(self, response, controller):
+        if not response: return
+
+        uri = response[0]["uri"]
+        self.context._prompt_goto_request(uri, response[0]["range"])
+
+    def _handle_diagnostics(self, params):
+        if not params: return
+
+        uri = params.get("uri", "")
+        diagnostics = params.get("diagnostics", [])
+
+        errors   = []
+        warnings = []
+        hints    = []
+
+        for diag in diagnostics:
+            severity  = diag.get("severity", 1)
+            message   = diag.get("message", "")
+            range     = diag.get("range", {})
+
+            diag_info = {
+                "message": message,
+                "range": range
+            }
+
+            if severity == 1:
+                errors.append(diag_info)
+            elif severity == 2:
+                warnings.append(diag_info)
+            elif severity == 3:
+                hints.append(diag_info)
+
+        self.response_cache.lsp_diagnostics = {
+            "uri":      uri,
+            "errors":   errors,
+            "warnings": warnings,
+            "hints":    hints
+        }
+
+        logger.debug(f"LSP Diagnostics for {uri}: {len(errors)} errors, {len(warnings)} warnings, {len(hints)} hints")

plugins/code/ui/lsp_manager/handlers/java.py

@@ -0,0 +1,51 @@
+# Python imports
+
+# Lib imports
+import gi
+gi.require_version('GtkSource', '4')
+
+from gi.repository import GtkSource
+
+# Application imports
+from libs.event_factory import Event_Factory, Code_Event_Types
+
+from .default import DefaultHandler
+
+
+
+class JavaHandler(DefaultHandler):
+    """Java-specific: overrides definition, handles classFileContents."""
+
+    def handle(self, method: str, response, controller):
+        match method:
+            case "textDocument/definition":
+                self._handle_definition(response, controller)
+            case "java/classFileContents":
+                self._handle_class_file_contents(response)
+            case _:
+                super().handle(method, response, controller)
+
+    def _handle_definition(self, response, controller):
+        if not response: return
+
+        uri = response[0]["uri"]
+        if "jdt://" in uri:
+            controller._lsp_java_class_file_contents(uri)
+            return
+
+        self.context._prompt_goto_request(uri, response[0]["range"])
+
+    def _handle_class_file_contents(self, text: str):
+        event = Event_Factory.create_event("get_active_view")
+        self.context.emit_to("source_views", event)
+
+        view = event.response
+        file = view.command.exec("new_file")
+        buffer = view.get_buffer()
+        itr = buffer.get_iter_at_mark(buffer.get_insert())
+        lm = GtkSource.LanguageManager.get_default()
+        language = lm.get_language("java")
+        file.ftype = "java"
+
+        buffer.set_language(language)
+        buffer.insert(itr, text, -1)

plugins/code/ui/lsp_manager/handlers/python.py

@@ -0,0 +1,12 @@
+# Python imports
+
+# Lib imports
+
+# Application imports
+from .default import DefaultHandler
+
+
+
+class PythonHandler(DefaultHandler):
+    """Uses default handling, can override if Python needs special logic."""
+    ...

plugins/code/ui/lsp_manager/handlers/registry.py

@@ -0,0 +1,49 @@
+# Python imports
+
+# Lib imports
+
+# Application imports
+from ..mixins.lsp_server_events_mixin import LSPServerEventsMixin
+
+from .base import BaseHandler
+from .default import DefaultHandler
+from .python import PythonHandler
+from .java import JavaHandler
+
+
+
+class HandlerRegistry(LSPServerEventsMixin):
+    def __init__(self):
+
+        self._instances: dict         = {}
+        self._lang_handlers: dict     = {
+            "default": DefaultHandler,
+            "python": PythonHandler,
+            "java": JavaHandler,
+        }
+
+
+    def _get_instance(self, handler_cls: type[BaseHandler]) -> BaseHandler:
+        if handler_cls in self._instances: return self._instances[handler_cls]
+
+        self._instances[handler_cls] = handler_cls()
+
+        return self._instances[handler_cls]
+
+    def register_handler(self, lang_id: str, handler_cls: type[BaseHandler]):
+        self._lang_handlers[lang_id] = handler_cls
+
+    def get_handler(self, lang_id: str = "", method: str = ""):
+        handler_cls = self._lang_handlers.get(
+            lang_id, self._lang_handlers.get("default", DefaultHandler)
+        )
+        
+        if not handler_cls: return None
+
+        return self._get_instance(handler_cls)
+
+    def close_handler(self, lang_id: str):
+        if not lang_id in self._lang_handlers: return
+
+        handler_cls = self._lang_handlers[lang_id]
+        self._instances.pop(handler_cls, None)