all

2026-02-15 15:55:49 +08:00
commit 23decb8687
32 changed files with 3822 additions and 0 deletions
--- a/.claude/settings.local.json
+++ b/.claude/settings.local.json
@@ -0,0 +1,14 @@
+{
+  "permissions": {
+    "allow": [
+      "Bash(npm create:*)",
+      "Bash(yes:*)",
+      "Bash(npx --yes create-vite@latest:*)",
+      "Bash(npm install)",
+      "Bash(npx vue-tsc:*)",
+      "Bash(curl:*)",
+      "Bash(pkill:*)",
+      "Bash(npx vite build)"
+    ]
+  }
+}
--- a/.gitignore
+++ b/.gitignore
@@ -0,0 +1,2 @@
+node_modules
+dist
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -0,0 +1,51 @@
+# Repository Guidelines
+
+## Project Structure & Module Organization
+This repository is a Vite + Vue 3 + TypeScript frontend app.
+
+- `src/`: application source code
+- `src/components/`: Vue UI components (for example, `MonacoEditor.vue`, `ThemeToggle.vue`)
+- `src/api/`: HTTP client logic (`completion.ts`)
+- `src/types/`: shared TypeScript interfaces for API payloads
+- `public/`: static assets served as-is
+- `dist/`: production build output (generated)
+- `backend/`: placeholder folder; no active backend code is currently committed
+
+Use the `@` alias for imports from `src` (configured in `vite.config.ts` and `tsconfig.app.json`).
+
+## Build, Test, and Development Commands
+- `npm install`: install dependencies.
+- `npm run dev`: start local development server with HMR.
+- `npm run build`: run type checks (`vue-tsc -b`) and build production assets.
+- `npm run preview`: serve the built app locally for verification.
+
+Current package scripts do not include linting or unit test commands.
+
+## Coding Style & Naming Conventions
+- Use Vue 3 Composition API with `<script setup lang="ts">`.
+- Use TypeScript strict mode patterns; avoid `any` unless justified.
+- Use 2-space indentation and single quotes, matching existing files.
+- Name components in PascalCase (e.g., `MonacoEditor.vue`).
+- Name composables/helpers and API modules in camelCase (e.g., `fetchCompletions`).
+- Keep shared interfaces in `src/types/*` and colocate feature-specific logic where used.
+
+## Testing Guidelines
+No automated test framework is configured yet in `package.json`.
+
+When adding tests, prefer Vitest + Vue Test Utils and place files as:
+- `src/**/__tests__/*.spec.ts`
+
+Minimum verification for every change:
+1. `npm run build` succeeds.
+2. `npm run dev` runs without console/runtime errors for the changed flow.
+
+## Commit & Pull Request Guidelines
+Git history is not available in this workspace snapshot, so no existing commit pattern can be inferred. Use Conventional Commits going forward:
+- `feat: add completion request timeout`
+- `fix: handle empty completion response`
+
+PRs should include:
+1. Clear summary of user-visible and technical changes.
+2. Linked issue/task ID (if applicable).
+3. Validation steps and commands run.
+4. Screenshots or short recordings for UI changes.
--- a/backend/.claude/settings.local.json
+++ b/backend/.claude/settings.local.json
@@ -0,0 +1,14 @@
+{
+  "permissions": {
+    "allow": [
+      "Bash(gopls version:*)",
+      "Bash(go version:*)",
+      "Bash(go env:*)",
+      "Bash(gopls help:*)",
+      "WebSearch",
+      "WebFetch(domain:microsoft.github.io)",
+      "WebFetch(domain:github.com)",
+      "WebFetch(domain:raw.githubusercontent.com)"
+    ]
+  }
+}
--- a/backend/README.md
+++ b/backend/README.md
@@ -0,0 +1,88 @@
+# Monaco Go Completion Backend
+
+Gin + gopls(JSON-RPC/LSP over stdio) 实现的 Go 代码补全后端。
+
+## 运行
+
+```bash
+go mod tidy
+go run ./cmd/server
+```
+
+默认监听 `http://localhost:8080`。
+
+## 环境变量
+
+- `PORT`：HTTP 端口，默认 `8080`
+- `GOPLS_PATH`：`gopls` 可执行文件路径，默认 `gopls`
+- `WORKSPACE_DIR`：gopls 工作目录，默认当前目录
+- `CORS_ALLOW_ORIGIN`：CORS 允许来源，默认 `*`
+
+## API
+
+### 健康检查
+
+- `GET /health`
+
+### Go 补全
+
+- `POST /api/v1/completions/go`
+- `Content-Type: application/json`
+
+### Go 补全（WebSocket）
+
+- `GET /ws/completions/go`
+- 客户端发送：
+
+```json
+{
+  "id": "1",
+  "uri": "file:///main.go",
+  "text": "package main\n\nimport \"fmt\"\n\nfunc main() {\n    fmt.Pri\n}",
+  "line": 5,
+  "character": 11
+}
+```
+
+- 服务端返回：
+
+```json
+{
+  "id": "1",
+  "items": [{ "label": "Println" }],
+  "isIncomplete": false
+}
+```
+
+请求体：
+
+```json
+{
+  "uri": "file:///C:/Users/meowr/Desktop/bishe/monica_editor_with_code_completion/backend/playground.go",
+  "text": "package main\n\nimport \"fmt\"\n\nfunc main() {\n    fmt.Pri\n}",
+  "line": 5,
+  "character": 11
+}
+```
+
+说明：
+- `uri` 建议使用绝对 `file://` URI（与 `WORKSPACE_DIR` 在同一工作区最稳定）。
+- 也支持 `file:///main.go` 这类相对根路径 URI，后端会自动映射到 `WORKSPACE_DIR` 下。
+- `line` / `character` 为 0-based。
+- 每次请求都要传前端当前全文 `text`。
+
+响应体：
+
+```json
+{
+  "items": [
+    {
+      "label": "Println",
+      "kind": 3,
+      "detail": "func(a ...any) (n int, err error)",
+      "documentation": "Println formats using the default formats..."
+    }
+  ],
+  "isIncomplete": false
+}
+```
--- a/backend/cmd/server/main.go
+++ b/backend/cmd/server/main.go
@@ -0,0 +1,105 @@
+package main
+
+import (
+	"context"
+	"log"
+	"net/http"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+
+	"github.com/gin-gonic/gin"
+
+	"monica-go-completion-backend/internal/api"
+	"monica-go-completion-backend/internal/completion"
+	"monica-go-completion-backend/internal/lsp"
+)
+
+type config struct {
+	Port         string
+	GoplsPath    string
+	WorkspaceDir string
+	AllowOrigin  string
+}
+
+func main() {
+	cfg := loadConfig()
+
+	lspClient, err := lsp.NewClient(context.Background(), cfg.GoplsPath, cfg.WorkspaceDir)
+	if err != nil {
+		log.Fatalf("create gopls client failed: %v", err)
+	}
+	defer func() {
+		_ = lspClient.Close()
+	}()
+
+	completionService := completion.NewService(lspClient)
+
+	router := gin.New()
+	router.Use(gin.Logger())
+	router.Use(gin.Recovery())
+	router.Use(corsMiddleware(cfg.AllowOrigin))
+	api.RegisterRoutes(router, completionService)
+
+	server := &http.Server{
+		Addr:         ":" + cfg.Port,
+		Handler:      router,
+		ReadTimeout:  30 * time.Second,
+		WriteTimeout: 30 * time.Second,
+		IdleTimeout:  60 * time.Second,
+	}
+
+	go func() {
+		log.Printf("completion backend listening on :%s", cfg.Port)
+		if err := server.ListenAndServe(); err != nil && err != http.ErrServerClosed {
+			log.Fatalf("http server failed: %v", err)
+		}
+	}()
+
+	sigCh := make(chan os.Signal, 1)
+	signal.Notify(sigCh, os.Interrupt, syscall.SIGTERM)
+	<-sigCh
+
+	shutdownCtx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	if err := server.Shutdown(shutdownCtx); err != nil {
+		log.Printf("http shutdown failed: %v", err)
+	}
+}
+
+func loadConfig() config {
+	cwd, err := os.Getwd()
+	if err != nil {
+		cwd = "."
+	}
+	return config{
+		Port:         getenv("PORT", "8080"),
+		GoplsPath:    getenv("GOPLS_PATH", "gopls"),
+		WorkspaceDir: getenv("WORKSPACE_DIR", cwd),
+		AllowOrigin:  getenv("CORS_ALLOW_ORIGIN", "*"),
+	}
+}
+
+func getenv(key, fallback string) string {
+	v := os.Getenv(key)
+	if v == "" {
+		return fallback
+	}
+	return v
+}
+
+func corsMiddleware(allowOrigin string) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		c.Header("Access-Control-Allow-Origin", allowOrigin)
+		c.Header("Access-Control-Allow-Methods", "GET,POST,OPTIONS")
+		c.Header("Access-Control-Allow-Headers", "Content-Type,Authorization")
+
+		if c.Request.Method == http.MethodOptions {
+			c.AbortWithStatus(http.StatusNoContent)
+			return
+		}
+		c.Next()
+	}
+}
--- a/backend/go.mod
+++ b/backend/go.mod
@@ -0,0 +1,42 @@
+module monica-go-completion-backend
+
+go 1.25
+
+require (
+	github.com/gin-gonic/gin v1.11.0
+	github.com/gorilla/websocket v1.5.3
+)
+
+require (
+	github.com/bytedance/sonic v1.14.0 // indirect
+	github.com/bytedance/sonic/loader v0.3.0 // indirect
+	github.com/cloudwego/base64x v0.1.6 // indirect
+	github.com/gabriel-vasile/mimetype v1.4.8 // indirect
+	github.com/gin-contrib/sse v1.1.0 // indirect
+	github.com/go-playground/locales v0.14.1 // indirect
+	github.com/go-playground/universal-translator v0.18.1 // indirect
+	github.com/go-playground/validator/v10 v10.27.0 // indirect
+	github.com/goccy/go-json v0.10.2 // indirect
+	github.com/goccy/go-yaml v1.18.0 // indirect
+	github.com/json-iterator/go v1.1.12 // indirect
+	github.com/klauspost/cpuid/v2 v2.3.0 // indirect
+	github.com/leodido/go-urn v1.4.0 // indirect
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421 // indirect
+	github.com/modern-go/reflect2 v1.0.2 // indirect
+	github.com/pelletier/go-toml/v2 v2.2.4 // indirect
+	github.com/quic-go/qpack v0.5.1 // indirect
+	github.com/quic-go/quic-go v0.54.0 // indirect
+	github.com/twitchyliquid64/golang-asm v0.15.1 // indirect
+	github.com/ugorji/go/codec v1.3.0 // indirect
+	go.uber.org/mock v0.5.0 // indirect
+	golang.org/x/arch v0.20.0 // indirect
+	golang.org/x/crypto v0.40.0 // indirect
+	golang.org/x/mod v0.25.0 // indirect
+	golang.org/x/net v0.42.0 // indirect
+	golang.org/x/sync v0.16.0 // indirect
+	golang.org/x/sys v0.35.0 // indirect
+	golang.org/x/text v0.27.0 // indirect
+	golang.org/x/tools v0.34.0 // indirect
+	google.golang.org/protobuf v1.36.9 // indirect
+)
--- a/backend/go.sum
+++ b/backend/go.sum
@@ -0,0 +1,90 @@
+github.com/bytedance/sonic v1.14.0 h1:/OfKt8HFw0kh2rj8N0F6C/qPGRESq0BbaNZgcNXXzQQ=
+github.com/bytedance/sonic v1.14.0/go.mod h1:WoEbx8WTcFJfzCe0hbmyTGrfjt8PzNEBdxlNUO24NhA=
+github.com/bytedance/sonic/loader v0.3.0 h1:dskwH8edlzNMctoruo8FPTJDF3vLtDT0sXZwvZJyqeA=
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+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
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+golang.org/x/arch v0.20.0/go.mod h1:bdwinDaKcfZUGpH09BB7ZmOfhalA8lQdzl62l8gGWsk=
+golang.org/x/crypto v0.40.0 h1:r4x+VvoG5Fm+eJcxMaY8CQM7Lb0l1lsmjGBQ6s8BfKM=
+golang.org/x/crypto v0.40.0/go.mod h1:Qr1vMER5WyS2dfPHAlsOj01wgLbsyWtFn/aY+5+ZdxY=
+golang.org/x/mod v0.25.0 h1:n7a+ZbQKQA/Ysbyb0/6IbB1H/X41mKgbhfv7AfG/44w=
+golang.org/x/mod v0.25.0/go.mod h1:IXM97Txy2VM4PJ3gI61r1YEk/gAj6zAHN3AdZt6S9Ww=
+golang.org/x/net v0.42.0 h1:jzkYrhi3YQWD6MLBJcsklgQsoAcw89EcZbJw8Z614hs=
+golang.org/x/net v0.42.0/go.mod h1:FF1RA5d3u7nAYA4z2TkclSCKh68eSXtiFwcWQpPXdt8=
+golang.org/x/sync v0.16.0 h1:ycBJEhp9p4vXvUZNszeOq0kGTPghopOL8q0fq3vstxw=
+golang.org/x/sync v0.16.0/go.mod h1:1dzgHSNfp02xaA81J2MS99Qcpr2w7fw1gpm99rleRqA=
+golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.35.0 h1:vz1N37gP5bs89s7He8XuIYXpyY0+QlsKmzipCbUtyxI=
+golang.org/x/sys v0.35.0/go.mod h1:BJP2sWEmIv4KK5OTEluFJCKSidICx8ciO85XgH3Ak8k=
+golang.org/x/text v0.27.0 h1:4fGWRpyh641NLlecmyl4LOe6yDdfaYNrGb2zdfo4JV4=
+golang.org/x/text v0.27.0/go.mod h1:1D28KMCvyooCX9hBiosv5Tz/+YLxj0j7XhWjpSUF7CU=
+golang.org/x/tools v0.34.0 h1:qIpSLOxeCYGg9TrcJokLBG4KFA6d795g0xkBkiESGlo=
+golang.org/x/tools v0.34.0/go.mod h1:pAP9OwEaY1CAW3HOmg3hLZC5Z0CCmzjAF2UQMSqNARg=
+google.golang.org/protobuf v1.36.9 h1:w2gp2mA27hUeUzj9Ex9FBjsBm40zfaDtEWow293U7Iw=
+google.golang.org/protobuf v1.36.9/go.mod h1:fuxRtAxBytpl4zzqUh6/eyUujkJdNiuEkXntxiD/uRU=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
--- a/backend/internal/api/handler.go
+++ b/backend/internal/api/handler.go
@@ -0,0 +1,43 @@
+package api
+
+import (
+	"context"
+	"errors"
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+
+	"monica-go-completion-backend/internal/completion"
+)
+
+type CompletionService interface {
+	Complete(ctx context.Context, req completion.Request) (completion.Response, error)
+}
+
+func RegisterRoutes(router *gin.Engine, service CompletionService) {
+	router.GET("/health", func(c *gin.Context) {
+		c.JSON(http.StatusOK, gin.H{"status": "ok"})
+	})
+
+	registerWSRoutes(router, service)
+
+	router.POST("/api/v1/completions/go", func(c *gin.Context) {
+		var req completion.Request
+		if err := c.ShouldBindJSON(&req); err != nil {
+			c.JSON(http.StatusBadRequest, gin.H{"error": "invalid JSON payload"})
+			return
+		}
+
+		resp, err := service.Complete(c.Request.Context(), req)
+		if err != nil {
+			if errors.Is(err, completion.ErrInvalidRequest) {
+				c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+				return
+			}
+			c.JSON(http.StatusInternalServerError, gin.H{"error": "completion failed"})
+			return
+		}
+
+		c.JSON(http.StatusOK, resp)
+	})
+}
--- a/backend/internal/api/handler_test.go
+++ b/backend/internal/api/handler_test.go
@@ -0,0 +1,171 @@
+package api
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"errors"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/gin-gonic/gin"
+	"github.com/gorilla/websocket"
+
+	"monica-go-completion-backend/internal/completion"
+)
+
+type fakeCompletionService struct {
+	resp completion.Response
+	err  error
+}
+
+func (f *fakeCompletionService) Complete(_ context.Context, _ completion.Request) (completion.Response, error) {
+	if f.err != nil {
+		return completion.Response{}, f.err
+	}
+	return f.resp, nil
+}
+
+func TestRegisterRoutesCompletionSuccess(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+	r := gin.New()
+	RegisterRoutes(r, &fakeCompletionService{
+		resp: completion.Response{Items: []completion.Item{{Label: "Println"}}, IsIncomplete: true},
+	})
+
+	body, _ := json.Marshal(map[string]any{
+		"uri":       "file:///main.go",
+		"text":      "package main",
+		"line":      0,
+		"character": 0,
+	})
+
+	req := httptest.NewRequest(http.MethodPost, "/api/v1/completions/go", bytes.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected status 200, got %d", w.Code)
+	}
+
+	var got struct {
+		Items        []completion.Item `json:"items"`
+		IsIncomplete bool              `json:"isIncomplete"`
+	}
+	if err := json.Unmarshal(w.Body.Bytes(), &got); err != nil {
+		t.Fatalf("failed to decode response: %v", err)
+	}
+	if len(got.Items) != 1 || got.Items[0].Label != "Println" || !got.IsIncomplete {
+		t.Fatalf("unexpected response body: %s", w.Body.String())
+	}
+}
+
+func TestRegisterRoutesCompletionBadJSON(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+	r := gin.New()
+	RegisterRoutes(r, &fakeCompletionService{})
+
+	req := httptest.NewRequest(http.MethodPost, "/api/v1/completions/go", bytes.NewReader([]byte("not-json")))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, req)
+
+	if w.Code != http.StatusBadRequest {
+		t.Fatalf("expected status 400, got %d", w.Code)
+	}
+}
+
+func TestRegisterRoutesCompletionValidationError(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+	r := gin.New()
+	rv := &fakeCompletionService{err: completion.ErrInvalidRequest}
+	RegisterRoutes(r, rv)
+
+	body, _ := json.Marshal(map[string]any{
+		"uri":       "",
+		"text":      "",
+		"line":      -1,
+		"character": 0,
+	})
+	w := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodPost, "/api/v1/completions/go", bytes.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+	r.ServeHTTP(w, req)
+
+	if w.Code != http.StatusBadRequest {
+		t.Fatalf("expected status 400, got %d", w.Code)
+	}
+}
+
+func TestRegisterRoutesCompletionServerError(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+	r := gin.New()
+	RegisterRoutes(r, &fakeCompletionService{err: errors.New("boom")})
+
+	body, _ := json.Marshal(map[string]any{
+		"uri":       "file:///main.go",
+		"text":      "package main",
+		"line":      0,
+		"character": 0,
+	})
+	w := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodPost, "/api/v1/completions/go", bytes.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+	r.ServeHTTP(w, req)
+
+	if w.Code != http.StatusInternalServerError {
+		t.Fatalf("expected status 500, got %d", w.Code)
+	}
+}
+
+func TestRegisterRoutesCompletionWebSocketSuccess(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+	r := gin.New()
+	RegisterRoutes(r, &fakeCompletionService{
+		resp: completion.Response{Items: []completion.Item{{Label: "Println"}}, IsIncomplete: false},
+	})
+
+	srv := httptest.NewServer(r)
+	defer srv.Close()
+
+	wsURL := "ws" + strings.TrimPrefix(srv.URL, "http") + "/ws/completions/go"
+	conn, _, err := websocket.DefaultDialer.Dial(wsURL, nil)
+	if err != nil {
+		t.Fatalf("websocket dial failed: %v", err)
+	}
+	defer conn.Close()
+
+	req := map[string]any{
+		"id":        "1",
+		"uri":       "file:///main.go",
+		"text":      "package main",
+		"line":      0,
+		"character": 0,
+	}
+	if err := conn.WriteJSON(req); err != nil {
+		t.Fatalf("WriteJSON() failed: %v", err)
+	}
+
+	var resp struct {
+		ID           string            `json:"id"`
+		Items        []completion.Item `json:"items"`
+		IsIncomplete bool              `json:"isIncomplete"`
+		Error        string            `json:"error"`
+	}
+	if err := conn.ReadJSON(&resp); err != nil {
+		t.Fatalf("ReadJSON() failed: %v", err)
+	}
+
+	if resp.Error != "" {
+		t.Fatalf("unexpected websocket error: %s", resp.Error)
+	}
+	if resp.ID != "1" {
+		t.Fatalf("unexpected id: %s", resp.ID)
+	}
+	if len(resp.Items) != 1 || resp.Items[0].Label != "Println" {
+		t.Fatalf("unexpected items: %+v", resp.Items)
+	}
+}
--- a/backend/internal/api/ws_handler.go
+++ b/backend/internal/api/ws_handler.go
@@ -0,0 +1,101 @@
+package api
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"net/http"
+	"sync"
+	"time"
+
+	"github.com/gin-gonic/gin"
+	"github.com/gorilla/websocket"
+
+	"monica-go-completion-backend/internal/completion"
+)
+
+var wsUpgrader = websocket.Upgrader{
+	ReadBufferSize:  4096,
+	WriteBufferSize: 4096,
+	CheckOrigin: func(_ *http.Request) bool {
+		return true
+	},
+}
+
+type wsCompletionRequest struct {
+	ID        string `json:"id"`
+	URI       string `json:"uri"`
+	Text      string `json:"text"`
+	Line      int    `json:"line"`
+	Character int    `json:"character"`
+}
+
+type wsCompletionResponse struct {
+	ID           string            `json:"id"`
+	Items        []completion.Item `json:"items,omitempty"`
+	IsIncomplete bool              `json:"isIncomplete,omitempty"`
+	Error        string            `json:"error,omitempty"`
+}
+
+func registerWSRoutes(router *gin.Engine, service CompletionService) {
+	router.GET("/ws/completions/go", func(c *gin.Context) {
+		conn, err := wsUpgrader.Upgrade(c.Writer, c.Request, nil)
+		if err != nil {
+			return
+		}
+		defer conn.Close()
+
+		var writeMu sync.Mutex
+
+		for {
+			_, payload, err := conn.ReadMessage()
+			if err != nil {
+				break
+			}
+
+			var req wsCompletionRequest
+			if err := json.Unmarshal(payload, &req); err != nil {
+				sendWSResponse(conn, &writeMu, wsCompletionResponse{
+					ID:    "",
+					Error: "invalid JSON payload",
+				})
+				continue
+			}
+
+			go func(r wsCompletionRequest) {
+				ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+				defer cancel()
+
+				resp, err := service.Complete(ctx, completion.Request{
+					URI:       r.URI,
+					Text:      r.Text,
+					Line:      r.Line,
+					Character: r.Character,
+				})
+				if err != nil {
+					msg := "completion failed"
+					if errors.Is(err, completion.ErrInvalidRequest) {
+						msg = err.Error()
+					}
+					sendWSResponse(conn, &writeMu, wsCompletionResponse{
+						ID:    r.ID,
+						Error: msg,
+					})
+					return
+				}
+
+				sendWSResponse(conn, &writeMu, wsCompletionResponse{
+					ID:           r.ID,
+					Items:        resp.Items,
+					IsIncomplete: resp.IsIncomplete,
+				})
+			}(req)
+		}
+	})
+}
+
+func sendWSResponse(conn *websocket.Conn, writeMu *sync.Mutex, resp wsCompletionResponse) {
+	writeMu.Lock()
+	defer writeMu.Unlock()
+	_ = conn.WriteJSON(resp)
+}
--- a/backend/internal/completion/service.go
+++ b/backend/internal/completion/service.go
@@ -0,0 +1,95 @@
+package completion
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"sync"
+)
+
+var ErrInvalidRequest = errors.New("invalid completion request")
+
+type Request struct {
+	URI       string `json:"uri"`
+	Text      string `json:"text"`
+	Line      int    `json:"line"`
+	Character int    `json:"character"`
+}
+
+type Item struct {
+	Label         string `json:"label"`
+	Kind          int    `json:"kind,omitempty"`
+	Detail        string `json:"detail,omitempty"`
+	Documentation string `json:"documentation,omitempty"`
+	InsertText    string `json:"insertText,omitempty"`
+	SortText      string `json:"sortText,omitempty"`
+	FilterText    string `json:"filterText,omitempty"`
+}
+
+type Response struct {
+	Items        []Item `json:"items"`
+	IsIncomplete bool   `json:"isIncomplete"`
+}
+
+type Client interface {
+	DidOpen(ctx context.Context, uri, text string, version int) error
+	DidChange(ctx context.Context, uri, text string, version int) error
+	Completion(ctx context.Context, uri string, line, character int) (Response, error)
+}
+
+type documentState struct {
+	version int
+}
+
+type Service struct {
+	client Client
+
+	mu        sync.Mutex
+	documents map[string]*documentState
+}
+
+func NewService(client Client) *Service {
+	return &Service{
+		client:    client,
+		documents: make(map[string]*documentState),
+	}
+}
+
+func (s *Service) Complete(ctx context.Context, req Request) (Response, error) {
+	if err := validateRequest(req); err != nil {
+		return Response{}, err
+	}
+
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	state, opened := s.documents[req.URI]
+	if !opened {
+		if err := s.client.DidOpen(ctx, req.URI, req.Text, 1); err != nil {
+			return Response{}, fmt.Errorf("didOpen failed: %w", err)
+		}
+		s.documents[req.URI] = &documentState{version: 1}
+	} else {
+		nextVersion := state.version + 1
+		if err := s.client.DidChange(ctx, req.URI, req.Text, nextVersion); err != nil {
+			return Response{}, fmt.Errorf("didChange failed: %w", err)
+		}
+		state.version = nextVersion
+	}
+
+	resp, err := s.client.Completion(ctx, req.URI, req.Line, req.Character)
+	if err != nil {
+		return Response{}, fmt.Errorf("completion failed: %w", err)
+	}
+	return resp, nil
+}
+
+func validateRequest(req Request) error {
+	if req.URI == "" {
+		return ErrInvalidRequest
+	}
+	if req.Line < 0 || req.Character < 0 {
+		return ErrInvalidRequest
+	}
+	return nil
+}
--- a/backend/internal/completion/service_test.go
+++ b/backend/internal/completion/service_test.go
@@ -0,0 +1,144 @@
+package completion
+
+import (
+	"context"
+	"errors"
+	"testing"
+)
+
+type fakeLSPClient struct {
+	openCalls       []openCall
+	changeCalls     []changeCall
+	completionCalls []completionCall
+	completionResp  Response
+	openErr         error
+	changeErr       error
+	completionErr   error
+}
+
+type openCall struct {
+	uri     string
+	text    string
+	version int
+}
+
+type changeCall struct {
+	uri     string
+	text    string
+	version int
+}
+
+type completionCall struct {
+	uri       string
+	line      int
+	character int
+}
+
+func (f *fakeLSPClient) DidOpen(_ context.Context, uri, text string, version int) error {
+	f.openCalls = append(f.openCalls, openCall{uri: uri, text: text, version: version})
+	return f.openErr
+}
+
+func (f *fakeLSPClient) DidChange(_ context.Context, uri, text string, version int) error {
+	f.changeCalls = append(f.changeCalls, changeCall{uri: uri, text: text, version: version})
+	return f.changeErr
+}
+
+func (f *fakeLSPClient) Completion(_ context.Context, uri string, line, character int) (Response, error) {
+	f.completionCalls = append(f.completionCalls, completionCall{uri: uri, line: line, character: character})
+	if f.completionErr != nil {
+		return Response{}, f.completionErr
+	}
+	return f.completionResp, nil
+}
+
+func TestServiceCompleteFirstRequestSendsDidOpen(t *testing.T) {
+	fake := &fakeLSPClient{
+		completionResp: Response{Items: []Item{{Label: "Println"}}, IsIncomplete: true},
+	}
+	svc := NewService(fake)
+
+	resp, err := svc.Complete(context.Background(), Request{
+		URI:       "file:///main.go",
+		Text:      "package main\nfunc main() { fmt.Pr }",
+		Line:      1,
+		Character: 23,
+	})
+	if err != nil {
+		t.Fatalf("Complete() error = %v", err)
+	}
+	if len(fake.openCalls) != 1 {
+		t.Fatalf("expected 1 didOpen call, got %d", len(fake.openCalls))
+	}
+	if fake.openCalls[0].version != 1 {
+		t.Fatalf("expected didOpen version=1, got %d", fake.openCalls[0].version)
+	}
+	if len(fake.changeCalls) != 0 {
+		t.Fatalf("expected 0 didChange calls, got %d", len(fake.changeCalls))
+	}
+	if len(fake.completionCalls) != 1 {
+		t.Fatalf("expected 1 completion call, got %d", len(fake.completionCalls))
+	}
+	if !resp.IsIncomplete || len(resp.Items) != 1 || resp.Items[0].Label != "Println" {
+		t.Fatalf("unexpected response: %+v", resp)
+	}
+}
+
+func TestServiceCompleteSecondRequestUsesDidChange(t *testing.T) {
+	fake := &fakeLSPClient{}
+	svc := NewService(fake)
+
+	_, err := svc.Complete(context.Background(), Request{
+		URI:       "file:///main.go",
+		Text:      "package main\nfunc main() {}",
+		Line:      1,
+		Character: 12,
+	})
+	if err != nil {
+		t.Fatalf("first Complete() error = %v", err)
+	}
+
+	_, err = svc.Complete(context.Background(), Request{
+		URI:       "file:///main.go",
+		Text:      "package main\nfunc main() { fmt.Pr }",
+		Line:      1,
+		Character: 23,
+	})
+	if err != nil {
+		t.Fatalf("second Complete() error = %v", err)
+	}
+
+	if len(fake.openCalls) != 1 {
+		t.Fatalf("expected 1 didOpen call, got %d", len(fake.openCalls))
+	}
+	if len(fake.changeCalls) != 1 {
+		t.Fatalf("expected 1 didChange call, got %d", len(fake.changeCalls))
+	}
+	if fake.changeCalls[0].version != 2 {
+		t.Fatalf("expected didChange version=2, got %d", fake.changeCalls[0].version)
+	}
+}
+
+func TestServiceCompleteValidatesRequest(t *testing.T) {
+	svc := NewService(&fakeLSPClient{})
+
+	_, err := svc.Complete(context.Background(), Request{URI: "", Text: "", Line: -1, Character: 0})
+	if !errors.Is(err, ErrInvalidRequest) {
+		t.Fatalf("expected ErrInvalidRequest, got %v", err)
+	}
+}
+
+func TestServiceCompleteReturnsClientError(t *testing.T) {
+	fake := &fakeLSPClient{openErr: errors.New("open failed")}
+	svc := NewService(fake)
+
+	_, err := svc.Complete(context.Background(), Request{
+		URI:       "file:///main.go",
+		Text:      "package main",
+		Line:      0,
+		Character: 0,
+	})
+	if err == nil {
+		t.Fatal("expected error, got nil")
+	}
+}
--- a/backend/internal/lsp/client.go
+++ b/backend/internal/lsp/client.go
@@ -0,0 +1,552 @@
+package lsp
+
+import (
+	"bufio"
+	"bytes"
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"net/url"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"regexp"
+	"strconv"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"monica-go-completion-backend/internal/completion"
+)
+
+var errClientClosed = errors.New("lsp client closed")
+
+type Client struct {
+	cmd   *exec.Cmd
+	stdin io.WriteCloser
+
+	writeMu sync.Mutex
+
+	nextID atomic.Int64
+
+	workspaceDir string
+
+	pendingMu sync.Mutex
+	pending   map[string]chan rpcResponse
+
+	exitCh    chan error
+	closeOnce sync.Once
+	closed    atomic.Bool
+}
+
+type rpcResponse struct {
+	result json.RawMessage
+	err    error
+}
+
+type rpcError struct {
+	Code    int             `json:"code"`
+	Message string          `json:"message"`
+	Data    json.RawMessage `json:"data,omitempty"`
+}
+
+type incomingEnvelope struct {
+	ID     *json.RawMessage `json:"id,omitempty"`
+	Result json.RawMessage  `json:"result,omitempty"`
+	Error  *rpcError        `json:"error,omitempty"`
+}
+
+type lspCompletionItem struct {
+	Label         string          `json:"label"`
+	Kind          int             `json:"kind,omitempty"`
+	Detail        string          `json:"detail,omitempty"`
+	InsertText    string          `json:"insertText,omitempty"`
+	SortText      string          `json:"sortText,omitempty"`
+	FilterText    string          `json:"filterText,omitempty"`
+	Documentation json.RawMessage `json:"documentation,omitempty"`
+}
+
+type lspCompletionList struct {
+	IsIncomplete bool                `json:"isIncomplete"`
+	Items        []lspCompletionItem `json:"items"`
+}
+
+func NewClient(parent context.Context, goplsPath, rootPath string) (*Client, error) {
+	if goplsPath == "" {
+		goplsPath = "gopls"
+	}
+	if rootPath == "" {
+		cwd, err := os.Getwd()
+		if err != nil {
+			return nil, fmt.Errorf("get working directory: %w", err)
+		}
+		rootPath = cwd
+	}
+
+	cmd := exec.Command(goplsPath)
+	stdin, err := cmd.StdinPipe()
+	if err != nil {
+		return nil, fmt.Errorf("create stdin pipe: %w", err)
+	}
+	stdout, err := cmd.StdoutPipe()
+	if err != nil {
+		return nil, fmt.Errorf("create stdout pipe: %w", err)
+	}
+	cmd.Stderr = os.Stderr
+
+	if err := cmd.Start(); err != nil {
+		return nil, fmt.Errorf("start gopls: %w", err)
+	}
+
+	client := &Client{
+		cmd:          cmd,
+		stdin:        stdin,
+		workspaceDir: rootPath,
+		pending:      make(map[string]chan rpcResponse),
+		exitCh:       make(chan error, 1),
+	}
+
+	go func() {
+		client.exitCh <- cmd.Wait()
+	}()
+	go client.readLoop(stdout)
+
+	initCtx, cancel := context.WithTimeout(parent, 10*time.Second)
+	defer cancel()
+
+	if err := client.initialize(initCtx, rootPath); err != nil {
+		_ = client.Close()
+		return nil, err
+	}
+
+	return client, nil
+}
+
+func (c *Client) initialize(ctx context.Context, rootPath string) error {
+	rootURI, err := pathToURI(rootPath)
+	if err != nil {
+		return fmt.Errorf("build root uri: %w", err)
+	}
+
+	params := map[string]any{
+		"processId": os.Getpid(),
+		"rootUri":   rootURI,
+		"capabilities": map[string]any{
+			"textDocument": map[string]any{
+				"completion": map[string]any{
+					"completionItem": map[string]any{
+						"snippetSupport": true,
+					},
+				},
+			},
+		},
+		"workspaceFolders": []map[string]string{
+			{
+				"uri":  rootURI,
+				"name": filepath.Base(rootPath),
+			},
+		},
+		"clientInfo": map[string]string{
+			"name":    "monica-go-completion-backend",
+			"version": "0.1.0",
+		},
+	}
+
+	var initResult json.RawMessage
+	if err := c.request(ctx, "initialize", params, &initResult); err != nil {
+		return fmt.Errorf("initialize request failed: %w", err)
+	}
+	if err := c.notify("initialized", map[string]any{}); err != nil {
+		return fmt.Errorf("initialized notification failed: %w", err)
+	}
+	return nil
+}
+
+func (c *Client) DidOpen(ctx context.Context, uri, text string, version int) error {
+	normalizedURI, err := c.normalizeURI(uri)
+	if err != nil {
+		return err
+	}
+
+	params := map[string]any{
+		"textDocument": map[string]any{
+			"uri":        normalizedURI,
+			"languageId": "go",
+			"version":    version,
+			"text":       text,
+		},
+	}
+	return c.notifyWithContext(ctx, "textDocument/didOpen", params)
+}
+
+func (c *Client) DidChange(ctx context.Context, uri, text string, version int) error {
+	normalizedURI, err := c.normalizeURI(uri)
+	if err != nil {
+		return err
+	}
+
+	params := map[string]any{
+		"textDocument": map[string]any{
+			"uri":     normalizedURI,
+			"version": version,
+		},
+		"contentChanges": []map[string]string{
+			{
+				"text": text,
+			},
+		},
+	}
+	return c.notifyWithContext(ctx, "textDocument/didChange", params)
+}
+
+func (c *Client) Completion(ctx context.Context, uri string, line, character int) (completion.Response, error) {
+	normalizedURI, err := c.normalizeURI(uri)
+	if err != nil {
+		return completion.Response{}, err
+	}
+
+	params := map[string]any{
+		"textDocument": map[string]string{
+			"uri": normalizedURI,
+		},
+		"position": map[string]int{
+			"line":      line,
+			"character": character,
+		},
+	}
+
+	var raw json.RawMessage
+	if err := c.request(ctx, "textDocument/completion", params, &raw); err != nil {
+		return completion.Response{}, err
+	}
+
+	body := bytes.TrimSpace(raw)
+	if len(body) == 0 || bytes.Equal(body, []byte("null")) {
+		return completion.Response{}, nil
+	}
+
+	if body[0] == '[' {
+		var items []lspCompletionItem
+		if err := json.Unmarshal(body, &items); err != nil {
+			return completion.Response{}, fmt.Errorf("decode completion items: %w", err)
+		}
+		return completion.Response{Items: mapCompletionItems(items)}, nil
+	}
+
+	var list lspCompletionList
+	if err := json.Unmarshal(body, &list); err != nil {
+		return completion.Response{}, fmt.Errorf("decode completion list: %w", err)
+	}
+	return completion.Response{
+		Items:        mapCompletionItems(list.Items),
+		IsIncomplete: list.IsIncomplete,
+	}, nil
+}
+
+var windowsDrivePattern = regexp.MustCompile(`^[A-Za-z]:`)
+
+func (c *Client) normalizeURI(rawURI string) (string, error) {
+	if rawURI == "" {
+		return "", errors.New("empty uri")
+	}
+
+	u, err := url.Parse(rawURI)
+	if err != nil {
+		return "", fmt.Errorf("invalid uri: %w", err)
+	}
+	if u.Scheme != "file" {
+		return rawURI, nil
+	}
+
+	path := u.Path
+	if path == "" {
+		return rawURI, nil
+	}
+
+	var localPath string
+	trimmed := strings.TrimPrefix(path, "/")
+	if windowsDrivePattern.MatchString(trimmed) {
+		localPath = filepath.FromSlash(trimmed)
+	} else {
+		rel := strings.TrimLeft(trimmed, "/\\")
+		localPath = filepath.Join(c.workspaceDir, filepath.FromSlash(rel))
+	}
+
+	return pathToURI(localPath)
+}
+
+func (c *Client) Close() error {
+	c.closeOnce.Do(func() {
+		shutdownCtx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
+		defer cancel()
+
+		_ = c.request(shutdownCtx, "shutdown", map[string]any{}, nil)
+		_ = c.notify("exit", map[string]any{})
+		_ = c.stdin.Close()
+
+		select {
+		case <-c.exitCh:
+		case <-time.After(2 * time.Second):
+			if c.cmd.Process != nil {
+				_ = c.cmd.Process.Kill()
+			}
+			<-c.exitCh
+		}
+
+		c.closed.Store(true)
+		c.failPending(errClientClosed)
+	})
+	return nil
+}
+
+func (c *Client) request(ctx context.Context, method string, params any, out any) error {
+	if c.closed.Load() {
+		return errClientClosed
+	}
+
+	id := c.nextID.Add(1)
+	key := strconv.FormatInt(id, 10)
+	wait := make(chan rpcResponse, 1)
+
+	c.pendingMu.Lock()
+	c.pending[key] = wait
+	c.pendingMu.Unlock()
+
+	msg := map[string]any{
+		"jsonrpc": "2.0",
+		"id":      id,
+		"method":  method,
+		"params":  params,
+	}
+	if err := c.writeMessage(msg); err != nil {
+		c.removePending(key)
+		return err
+	}
+
+	select {
+	case <-ctx.Done():
+		c.removePending(key)
+		return ctx.Err()
+	case resp := <-wait:
+		if resp.err != nil {
+			return resp.err
+		}
+		if out != nil && len(resp.result) > 0 && !bytes.Equal(bytes.TrimSpace(resp.result), []byte("null")) {
+			if err := json.Unmarshal(resp.result, out); err != nil {
+				return fmt.Errorf("decode response for %s: %w", method, err)
+			}
+		}
+		return nil
+	}
+}
+
+func (c *Client) notify(method string, params any) error {
+	return c.notifyWithContext(context.Background(), method, params)
+}
+
+func (c *Client) notifyWithContext(ctx context.Context, method string, params any) error {
+	if c.closed.Load() {
+		return errClientClosed
+	}
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	default:
+	}
+
+	msg := map[string]any{
+		"jsonrpc": "2.0",
+		"method":  method,
+		"params":  params,
+	}
+	return c.writeMessage(msg)
+}
+
+func (c *Client) writeMessage(msg any) error {
+	payload, err := json.Marshal(msg)
+	if err != nil {
+		return fmt.Errorf("marshal json-rpc message: %w", err)
+	}
+
+	header := fmt.Sprintf("Content-Length: %d\r\n\r\n", len(payload))
+
+	c.writeMu.Lock()
+	defer c.writeMu.Unlock()
+
+	if _, err := io.WriteString(c.stdin, header); err != nil {
+		return fmt.Errorf("write lsp header: %w", err)
+	}
+	if _, err := c.stdin.Write(payload); err != nil {
+		return fmt.Errorf("write lsp payload: %w", err)
+	}
+	return nil
+}
+
+func (c *Client) readLoop(stdout io.Reader) {
+	reader := bufio.NewReader(stdout)
+	for {
+		body, err := readMessage(reader)
+		if err != nil {
+			c.failPending(fmt.Errorf("read lsp message: %w", err))
+			return
+		}
+		c.handleIncoming(body)
+	}
+}
+
+func readMessage(reader *bufio.Reader) ([]byte, error) {
+	contentLength := 0
+	for {
+		line, err := reader.ReadString('\n')
+		if err != nil {
+			return nil, err
+		}
+		line = strings.TrimRight(line, "\r\n")
+		if line == "" {
+			break
+		}
+
+		parts := strings.SplitN(line, ":", 2)
+		if len(parts) != 2 {
+			continue
+		}
+		if strings.EqualFold(strings.TrimSpace(parts[0]), "Content-Length") {
+			n, err := strconv.Atoi(strings.TrimSpace(parts[1]))
+			if err != nil {
+				return nil, fmt.Errorf("invalid content-length %q: %w", parts[1], err)
+			}
+			contentLength = n
+		}
+	}
+
+	if contentLength <= 0 {
+		return nil, errors.New("missing content-length")
+	}
+
+	body := make([]byte, contentLength)
+	if _, err := io.ReadFull(reader, body); err != nil {
+		return nil, err
+	}
+	return body, nil
+}
+
+func (c *Client) handleIncoming(body []byte) {
+	var envelope incomingEnvelope
+	if err := json.Unmarshal(body, &envelope); err != nil {
+		return
+	}
+
+	if envelope.ID == nil {
+		return
+	}
+
+	key := normalizeID(*envelope.ID)
+	if key == "" {
+		return
+	}
+
+	c.pendingMu.Lock()
+	wait := c.pending[key]
+	delete(c.pending, key)
+	c.pendingMu.Unlock()
+
+	if wait == nil {
+		return
+	}
+
+	if envelope.Error != nil {
+		wait <- rpcResponse{
+			err: fmt.Errorf("lsp error code=%d message=%s", envelope.Error.Code, envelope.Error.Message),
+		}
+		return
+	}
+
+	wait <- rpcResponse{result: envelope.Result}
+}
+
+func normalizeID(raw json.RawMessage) string {
+	raw = bytes.TrimSpace(raw)
+	if len(raw) == 0 {
+		return ""
+	}
+
+	if raw[0] == '"' {
+		var s string
+		if err := json.Unmarshal(raw, &s); err == nil {
+			return s
+		}
+	}
+	return string(raw)
+}
+
+func (c *Client) removePending(key string) {
+	c.pendingMu.Lock()
+	delete(c.pending, key)
+	c.pendingMu.Unlock()
+}
+
+func (c *Client) failPending(err error) {
+	c.pendingMu.Lock()
+	defer c.pendingMu.Unlock()
+
+	for key, wait := range c.pending {
+		delete(c.pending, key)
+		wait <- rpcResponse{err: err}
+	}
+}
+
+func mapCompletionItems(items []lspCompletionItem) []completion.Item {
+	out := make([]completion.Item, 0, len(items))
+	for _, it := range items {
+		out = append(out, completion.Item{
+			Label:         it.Label,
+			Kind:          it.Kind,
+			Detail:        it.Detail,
+			Documentation: decodeDocumentation(it.Documentation),
+			InsertText:    it.InsertText,
+			SortText:      it.SortText,
+			FilterText:    it.FilterText,
+		})
+	}
+	return out
+}
+
+func decodeDocumentation(raw json.RawMessage) string {
+	raw = bytes.TrimSpace(raw)
+	if len(raw) == 0 || bytes.Equal(raw, []byte("null")) {
+		return ""
+	}
+
+	if raw[0] == '"' {
+		var s string
+		if err := json.Unmarshal(raw, &s); err == nil {
+			return s
+		}
+		return ""
+	}
+
+	var markup struct {
+		Value string `json:"value"`
+	}
+	if err := json.Unmarshal(raw, &markup); err == nil && markup.Value != "" {
+		return markup.Value
+	}
+
+	return ""
+}
+
+func pathToURI(path string) (string, error) {
+	abs, err := filepath.Abs(path)
+	if err != nil {
+		return "", err
+	}
+	slashed := filepath.ToSlash(abs)
+	if !strings.HasPrefix(slashed, "/") {
+		slashed = "/" + slashed
+	}
+	u := url.URL{Scheme: "file", Path: slashed}
+	return u.String(), nil
+}
--- a/backend/internal/lsp/client_test.go
+++ b/backend/internal/lsp/client_test.go
@@ -0,0 +1,49 @@
+package lsp
+
+import (
+	"path/filepath"
+	"testing"
+)
+
+func TestNormalizeURIRebasesRelativeFileURI(t *testing.T) {
+	workspace, err := filepath.Abs(filepath.Join("testdata", "ws"))
+	if err != nil {
+		t.Fatalf("filepath.Abs() error = %v", err)
+	}
+
+	client := &Client{workspaceDir: workspace}
+	got, err := client.normalizeURI("file:///main.go")
+	if err != nil {
+		t.Fatalf("normalizeURI() error = %v", err)
+	}
+
+	want, err := pathToURI(filepath.Join(workspace, "main.go"))
+	if err != nil {
+		t.Fatalf("pathToURI() error = %v", err)
+	}
+	if got != want {
+		t.Fatalf("normalizeURI() = %q, want %q", got, want)
+	}
+}
+
+func TestNormalizeURIKeepsAbsoluteFileURI(t *testing.T) {
+	workspace, err := filepath.Abs(filepath.Join("testdata", "ws"))
+	if err != nil {
+		t.Fatalf("filepath.Abs() error = %v", err)
+	}
+
+	client := &Client{workspaceDir: workspace}
+	absPath := filepath.Join(workspace, "demo.go")
+	uri, err := pathToURI(absPath)
+	if err != nil {
+		t.Fatalf("pathToURI() error = %v", err)
+	}
+
+	got, err := client.normalizeURI(uri)
+	if err != nil {
+		t.Fatalf("normalizeURI() error = %v", err)
+	}
+	if got != uri {
+		t.Fatalf("normalizeURI() = %q, want %q", got, uri)
+	}
+}
--- a/env.d.ts
+++ b/env.d.ts
@@ -0,0 +1,7 @@
+/// <reference types="vite/client" />
+
+declare module '*.vue' {
+  import type { DefineComponent } from 'vue'
+  const component: DefineComponent<object, object, unknown>
+  export default component
+}
--- a/index.html
+++ b/index.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>Monica Editor</title>
+  </head>
+  <body>
+    <div id="app"></div>
+    <script type="module" src="/src/main.ts"></script>
+  </body>
+</html>
--- a/package-lock.json
+++ b/package-lock.json
--- a/package.json
+++ b/package.json
@@ -0,0 +1,21 @@
+{
+  "name": "monica-editor",
+  "private": true,
+  "version": "1.0.0",
+  "type": "module",
+  "scripts": {
+    "dev": "vite",
+    "build": "vue-tsc -b && vite build",
+    "preview": "vite preview"
+  },
+  "dependencies": {
+    "monaco-editor": "^0.52.2",
+    "vue": "^3.5.13"
+  },
+  "devDependencies": {
+    "@vitejs/plugin-vue": "^5.2.1",
+    "typescript": "~5.7.2",
+    "vite": "^6.2.0",
+    "vue-tsc": "^2.2.0"
+  }
+}
--- a/src/App.vue
+++ b/src/App.vue
@@ -0,0 +1,157 @@
+<script setup lang="ts">
+import { ref, computed } from 'vue'
+import MonacoEditor from './components/MonacoEditor.vue'
+import ThemeToggle from './components/ThemeToggle.vue'
+
+interface LanguageOption {
+  label: string
+  value: string
+}
+
+const isDark = ref(true)
+const theme = computed(() => (isDark.value ? 'vs-dark' : 'vs'))
+
+const languageOptions: LanguageOption[] = [
+  { label: 'Go', value: 'go' },
+  { label: 'JavaScript', value: 'javascript' },
+  { label: 'TypeScript', value: 'typescript' },
+  { label: 'Python', value: 'python' },
+  { label: 'Java', value: 'java' },
+  { label: 'JSON', value: 'json' },
+  { label: 'YAML', value: 'yaml' },
+  { label: 'Markdown', value: 'markdown' },
+  { label: 'HTML', value: 'html' },
+  { label: 'CSS', value: 'css' },
+  { label: 'SQL', value: 'sql' },
+  { label: 'Shell', value: 'shell' },
+]
+
+const initialCodeByLanguage: Record<string, string> = {
+  go: ['package main', '', 'import "fmt"', '', 'func main() {', '\tfmt.Println("Hello, World!")', '}'].join('\n'),
+  javascript: ['function hello() {', '  console.log("Hello, World!")', '}', '', 'hello();'].join('\n'),
+  typescript: [
+    'function greet(name: string): void {',
+    '  console.log(`Hello, ${name}`)',
+    '}',
+    '',
+    'greet("World")',
+  ].join('\n'),
+  python: ['def greet(name: str) -> None:', '    print(f"Hello, {name}")', '', 'greet("World")'].join('\n'),
+  java: [
+    'public class Main {',
+    '    public static void main(String[] args) {',
+    '        System.out.println("Hello, World!");',
+    '    }',
+    '}',
+  ].join('\n'),
+  json: ['{', '  "name": "monica-editor",', '  "version": "1.0.0"', '}'].join('\n'),
+  yaml: ['name: monica-editor', 'version: 1.0.0', 'enabled: true'].join('\n'),
+  markdown: ['# Monica Editor', '', '- Multi-language highlighting', '- Go completion backend'].join('\n'),
+  html: ['<!doctype html>', '<html>', '  <body>', '    <h1>Hello, World!</h1>', '  </body>', '</html>'].join('\n'),
+  css: ['body {', '  margin: 0;', '  font-family: sans-serif;', '}'].join('\n'),
+  sql: ['SELECT id, name', 'FROM users', 'WHERE active = true', 'ORDER BY id DESC;'].join('\n'),
+  shell: ['#!/usr/bin/env bash', 'echo "Hello, World!"'].join('\n'),
+}
+
+const selectedLanguage = ref<string>('go')
+const codeByLanguage = ref<Record<string, string>>({ ...initialCodeByLanguage })
+
+const currentCode = computed<string>({
+  get() {
+    return codeByLanguage.value[selectedLanguage.value] ?? ''
+  },
+  set(value: string) {
+    codeByLanguage.value[selectedLanguage.value] = value
+  },
+})
+
+function toggleTheme() {
+  isDark.value = !isDark.value
+}
+</script>
+
+<template>
+  <div class="app" :class="{ dark: isDark, light: !isDark }">
+    <header class="toolbar">
+      <span class="title">Monica Editor</span>
+      <div class="toolbar-controls">
+        <label class="language-label" for="language-select">Language</label>
+        <select id="language-select" v-model="selectedLanguage" class="language-select">
+          <option v-for="option in languageOptions" :key="option.value" :value="option.value">
+            {{ option.label }}
+          </option>
+        </select>
+        <ThemeToggle :isDark="isDark" @toggle="toggleTheme" />
+      </div>
+    </header>
+    <main class="editor-area">
+      <MonacoEditor v-model="currentCode" :language="selectedLanguage" :theme="theme" />
+    </main>
+  </div>
+</template>
+
+<style scoped>
+.app {
+  display: flex;
+  flex-direction: column;
+  width: 100%;
+  height: 100%;
+}
+
+.app.dark {
+  background: #1e1e1e;
+  color: #cccccc;
+}
+
+.app.light {
+  background: #ffffff;
+  color: #333333;
+}
+
+.toolbar {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  padding: 8px 16px;
+  height: 48px;
+  flex-shrink: 0;
+  border-bottom: 1px solid rgba(128, 128, 128, 0.3);
+}
+
+.toolbar-controls {
+  display: flex;
+  align-items: center;
+  gap: 10px;
+}
+
+.language-label {
+  font-size: 13px;
+  opacity: 0.8;
+}
+
+.language-select {
+  min-width: 148px;
+  height: 30px;
+  border-radius: 6px;
+  border: 1px solid rgba(128, 128, 128, 0.35);
+  padding: 0 10px;
+  background: transparent;
+  color: inherit;
+  outline: none;
+}
+
+.language-select:focus {
+  border-color: #2f81f7;
+}
+
+.title {
+  font-size: 15px;
+  font-weight: 600;
+  letter-spacing: 0.5px;
+}
+
+.editor-area {
+  flex: 1;
+  overflow: hidden;
+}
+</style>
--- a/src/api/completion.ts
+++ b/src/api/completion.ts
@@ -0,0 +1,161 @@
+import type { CompletionRequest, CompletionResponse } from '../types/completion'
+
+const COMPLETION_API_URL =
+  import.meta.env.VITE_COMPLETION_API_URL ??
+  'http://127.0.0.1:8080/api/v1/completions/go'
+const COMPLETION_WS_URL =
+  import.meta.env.VITE_COMPLETION_WS_URL ??
+  'ws://127.0.0.1:8080/ws/completions/go'
+
+const WS_TIMEOUT_MS = 1800
+
+interface WSCompletionResponse extends CompletionResponse {
+  id: string
+  error?: string
+}
+
+interface PendingRequest {
+  resolve: (value: CompletionResponse) => void
+  timer: number
+}
+
+let ws: WebSocket | null = null
+let wsConnecting: Promise<WebSocket> | null = null
+let nextRequestID = 0
+const pending = new Map<string, PendingRequest>()
+
+export async function fetchCompletions(
+  request: CompletionRequest,
+): Promise<CompletionResponse> {
+  try {
+    const socket = await getWebSocket()
+    if (socket.readyState === WebSocket.OPEN) {
+      return await fetchCompletionsByWS(socket, request)
+    }
+  } catch {
+    // Fallback to HTTP below.
+  }
+
+  return await fetchCompletionsByHTTP(request)
+}
+
+async function fetchCompletionsByHTTP(
+  request: CompletionRequest,
+): Promise<CompletionResponse> {
+  try {
+    const response = await fetch(COMPLETION_API_URL, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify(request),
+    })
+
+    if (!response.ok) {
+      console.error('Completion API error:', response.status)
+      return { items: [], isIncomplete: false }
+    }
+
+    return (await response.json()) as CompletionResponse
+  } catch (error) {
+    console.error('Completion API request failed:', error)
+    return { items: [], isIncomplete: false }
+  }
+}
+
+async function fetchCompletionsByWS(
+  socket: WebSocket,
+  request: CompletionRequest,
+): Promise<CompletionResponse> {
+  const id = String(++nextRequestID)
+
+  return await new Promise<CompletionResponse>((resolve) => {
+    const timer = window.setTimeout(async () => {
+      pending.delete(id)
+      resolve(await fetchCompletionsByHTTP(request))
+    }, WS_TIMEOUT_MS)
+
+    pending.set(id, { resolve, timer })
+
+    try {
+      socket.send(JSON.stringify({ id, ...request }))
+    } catch (error) {
+      window.clearTimeout(timer)
+      pending.delete(id)
+      console.error('Completion WS send failed:', error)
+      void fetchCompletionsByHTTP(request).then(resolve)
+    }
+  })
+}
+
+async function getWebSocket(): Promise<WebSocket> {
+  if (ws && ws.readyState === WebSocket.OPEN) {
+    return ws
+  }
+  if (wsConnecting) {
+    return await wsConnecting
+  }
+
+  wsConnecting = new Promise<WebSocket>((resolve, reject) => {
+    const socket = new WebSocket(COMPLETION_WS_URL)
+    let settled = false
+
+    socket.onopen = () => {
+      settled = true
+      ws = socket
+      wsConnecting = null
+      console.info('[completion] websocket connected:', COMPLETION_WS_URL)
+      resolve(socket)
+    }
+
+    socket.onmessage = (event) => {
+      if (typeof event.data !== 'string') return
+
+      let payload: WSCompletionResponse
+      try {
+        payload = JSON.parse(event.data) as WSCompletionResponse
+      } catch {
+        return
+      }
+
+      const entry = pending.get(payload.id)
+      if (!entry) return
+
+      window.clearTimeout(entry.timer)
+      pending.delete(payload.id)
+
+      if (payload.error) {
+        entry.resolve({ items: [], isIncomplete: false })
+        return
+      }
+
+      entry.resolve({
+        items: payload.items ?? [],
+        isIncomplete: payload.isIncomplete ?? false,
+      })
+    }
+
+    socket.onerror = () => {
+      if (settled) return
+      settled = true
+      wsConnecting = null
+      console.error('[completion] websocket connect failed:', COMPLETION_WS_URL)
+      reject(new Error('completion websocket connect failed'))
+    }
+
+    socket.onclose = () => {
+      console.warn('[completion] websocket closed')
+      ws = null
+      wsConnecting = null
+      flushPending()
+    }
+  })
+
+  return await wsConnecting
+}
+
+function flushPending() {
+  for (const [id, entry] of pending) {
+    window.clearTimeout(entry.timer)
+    pending.delete(id)
+    entry.resolve({ items: [], isIncomplete: false })
+  }
+}
--- a/src/components/MonacoEditor.vue
+++ b/src/components/MonacoEditor.vue
@@ -0,0 +1,217 @@
+<script setup lang="ts">
+import { ref, onMounted, onBeforeUnmount, watch, shallowRef } from 'vue'
+import * as monaco from 'monaco-editor'
+import { fetchCompletions } from '../api/completion'
+import type { CompletionItem } from '../types/completion'
+
+const props = withDefaults(
+  defineProps<{
+    modelValue?: string
+    language?: string
+    theme?: string
+  }>(),
+  {
+    modelValue: '',
+    language: 'go',
+    theme: 'vs-dark',
+  },
+)
+
+const emit = defineEmits<{
+  'update:modelValue': [value: string]
+}>()
+
+const editorContainer = ref<HTMLDivElement>()
+const editor = shallowRef<monaco.editor.IStandaloneCodeEditor>()
+let completionDisposable: monaco.IDisposable | null = null
+
+/** Map LSP CompletionItemKind to Monaco CompletionItemKind */
+function mapKind(kind?: number): monaco.languages.CompletionItemKind {
+  switch (kind) {
+    case 2:
+      return monaco.languages.CompletionItemKind.Method
+    case 3:
+      return monaco.languages.CompletionItemKind.Function
+    case 4:
+      return monaco.languages.CompletionItemKind.Constructor
+    case 5:
+      return monaco.languages.CompletionItemKind.Field
+    case 6:
+      return monaco.languages.CompletionItemKind.Variable
+    case 7:
+      return monaco.languages.CompletionItemKind.Class
+    case 8:
+      return monaco.languages.CompletionItemKind.Interface
+    case 9:
+      return monaco.languages.CompletionItemKind.Module
+    case 10:
+      return monaco.languages.CompletionItemKind.Property
+    case 11:
+      return monaco.languages.CompletionItemKind.Unit
+    case 12:
+      return monaco.languages.CompletionItemKind.Value
+    case 13:
+      return monaco.languages.CompletionItemKind.Enum
+    case 14:
+      return monaco.languages.CompletionItemKind.Keyword
+    case 15:
+      return monaco.languages.CompletionItemKind.Snippet
+    case 16:
+      return monaco.languages.CompletionItemKind.Color
+    case 17:
+      return monaco.languages.CompletionItemKind.File
+    case 18:
+      return monaco.languages.CompletionItemKind.Reference
+    case 19:
+      return monaco.languages.CompletionItemKind.Folder
+    case 20:
+      return monaco.languages.CompletionItemKind.EnumMember
+    case 21:
+      return monaco.languages.CompletionItemKind.Constant
+    case 22:
+      return monaco.languages.CompletionItemKind.Struct
+    case 23:
+      return monaco.languages.CompletionItemKind.Event
+    case 24:
+      return monaco.languages.CompletionItemKind.Operator
+    case 25:
+      return monaco.languages.CompletionItemKind.TypeParameter
+    default:
+      return monaco.languages.CompletionItemKind.Text
+  }
+}
+
+function getDocumentURI(language: string): string {
+  const name = `main.${language}`
+  return `file:///${name}`
+}
+
+/** Register the code completion provider for the given language */
+function registerCompletionProvider(language: string) {
+  completionDisposable?.dispose()
+  completionDisposable = null
+
+  // Currently only Go completion is wired to backend gopls.
+  if (language !== 'go') {
+    return
+  }
+
+  completionDisposable = monaco.languages.registerCompletionItemProvider(language, {
+    triggerCharacters: ['.', ':', '('],
+
+    async provideCompletionItems(model, position) {
+      if (model.getLanguageId() !== 'go') {
+        return { suggestions: [] }
+      }
+
+      const code = model.getValue()
+      const word = model.getWordUntilPosition(position)
+
+      const response = await fetchCompletions({
+        uri: getDocumentURI(language),
+        text: code,
+        line: Math.max(position.lineNumber - 1, 0),
+        character: Math.max(position.column - 1, 0),
+      })
+
+      const range = new monaco.Range(
+        position.lineNumber,
+        word.startColumn,
+        position.lineNumber,
+        word.endColumn,
+      )
+
+      const suggestions: monaco.languages.CompletionItem[] = response.items.map(
+        (item: CompletionItem) => ({
+          label: item.label,
+          kind: mapKind(item.kind),
+          insertText: item.insertText || item.label,
+          detail: item.detail,
+          documentation: item.documentation,
+          range,
+        }),
+      )
+
+      return { suggestions }
+    },
+  })
+}
+
+onMounted(() => {
+  if (!editorContainer.value) return
+
+  editor.value = monaco.editor.create(editorContainer.value, {
+    value: props.modelValue,
+    language: props.language,
+    theme: props.theme,
+    automaticLayout: true,
+    fontSize: 14,
+    lineNumbers: 'on',
+    minimap: { enabled: true },
+    scrollBeyondLastLine: false,
+    wordWrap: 'off',
+    tabSize: 4,
+    insertSpaces: false, // Go uses tabs
+    renderWhitespace: 'selection',
+    bracketPairColorization: { enabled: true },
+    suggestOnTriggerCharacters: true,
+    quickSuggestions: true,
+    parameterHints: { enabled: true },
+  })
+
+  // Sync content changes back to parent
+  editor.value.onDidChangeModelContent(() => {
+    const value = editor.value!.getValue()
+    emit('update:modelValue', value)
+  })
+
+  // Register completion provider
+  registerCompletionProvider(props.language)
+})
+
+// Watch for theme changes
+watch(
+  () => props.theme,
+  (newTheme) => {
+    monaco.editor.setTheme(newTheme)
+  },
+)
+
+// Watch for language changes
+watch(
+  () => props.language,
+  (newLang) => {
+    const model = editor.value?.getModel()
+    if (model) {
+      monaco.editor.setModelLanguage(model, newLang)
+    }
+    registerCompletionProvider(newLang)
+  },
+)
+
+// Watch for external modelValue changes
+watch(
+  () => props.modelValue,
+  (newValue) => {
+    if (editor.value && editor.value.getValue() !== newValue) {
+      editor.value.setValue(newValue)
+    }
+  },
+)
+
+onBeforeUnmount(() => {
+  completionDisposable?.dispose()
+  editor.value?.dispose()
+})
+</script>
+
+<template>
+  <div ref="editorContainer" class="editor-container" />
+</template>
+
+<style scoped>
+.editor-container {
+  width: 100%;
+  height: 100%;
+}
+</style>
--- a/src/components/ThemeToggle.vue
+++ b/src/components/ThemeToggle.vue
@@ -0,0 +1,40 @@
+<script setup lang="ts">
+defineProps<{
+  isDark: boolean
+}>()
+
+const emit = defineEmits<{
+  toggle: []
+}>()
+</script>
+
+<template>
+  <button class="theme-toggle" @click="emit('toggle')" :title="isDark ? 'Switch to light theme' : 'Switch to dark theme'">
+    <span v-if="isDark" class="icon">&#9728;</span>
+    <span v-else class="icon">&#9790;</span>
+  </button>
+</template>
+
+<style scoped>
+.theme-toggle {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  width: 36px;
+  height: 36px;
+  border: 1px solid rgba(255, 255, 255, 0.2);
+  border-radius: 6px;
+  background: transparent;
+  cursor: pointer;
+  transition: background 0.2s;
+}
+
+.theme-toggle:hover {
+  background: rgba(255, 255, 255, 0.1);
+}
+
+.icon {
+  font-size: 18px;
+  line-height: 1;
+}
+</style>
--- a/src/main.ts
+++ b/src/main.ts
@@ -0,0 +1,14 @@
+import { createApp } from 'vue'
+import App from './App.vue'
+import './style.css'
+
+// Monaco Editor worker setup — must run before any monaco import
+import editorWorker from 'monaco-editor/esm/vs/editor/editor.worker?worker'
+
+self.MonacoEnvironment = {
+  getWorker() {
+    return new editorWorker()
+  },
+}
+
+createApp(App).mount('#app')
--- a/src/style.css
+++ b/src/style.css
@@ -0,0 +1,19 @@
+*,
+*::before,
+*::after {
+  margin: 0;
+  padding: 0;
+  box-sizing: border-box;
+}
+
+html,
+body,
+#app {
+  width: 100%;
+  height: 100%;
+  overflow: hidden;
+}
+
+body {
+  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
+}
--- a/src/types/completion.ts
+++ b/src/types/completion.ts
@@ -0,0 +1,30 @@
+/** Types for the code completion API */
+
+export interface CompletionRequest {
+  /** Document URI (file://...) */
+  uri: string
+  /** The full text content of the editor */
+  text: string
+  /** Cursor line number (0-based) */
+  line: number
+  /** Cursor character number (0-based) */
+  character: number
+}
+
+export interface CompletionItem {
+  /** The text shown in the completion list */
+  label: string
+  /** The text to insert when the completion is accepted */
+  insertText?: string
+  /** Optional detail text (e.g., type info) */
+  detail?: string
+  /** Optional documentation */
+  documentation?: string
+  /** LSP CompletionItemKind (number) */
+  kind?: number
+}
+
+export interface CompletionResponse {
+  items: CompletionItem[]
+  isIncomplete?: boolean
+}
--- a/tsconfig.app.json
+++ b/tsconfig.app.json
@@ -0,0 +1,25 @@
+{
+  "compilerOptions": {
+    "target": "ES2020",
+    "useDefineForClassFields": true,
+    "module": "ESNext",
+    "lib": ["ES2020", "DOM", "DOM.Iterable"],
+    "skipLibCheck": true,
+    "moduleResolution": "bundler",
+    "allowImportingTsExtensions": true,
+    "isolatedModules": true,
+    "moduleDetection": "force",
+    "noEmit": true,
+    "jsx": "preserve",
+    "strict": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    "noFallthroughCasesInSwitch": true,
+    "noUncheckedSideEffectImports": true,
+    "baseUrl": ".",
+    "paths": {
+      "@/*": ["src/*"]
+    }
+  },
+  "include": ["src/**/*.ts", "src/**/*.tsx", "src/**/*.vue", "env.d.ts"]
+}
--- a/tsconfig.app.tsbuildinfo
+++ b/tsconfig.app.tsbuildinfo
@@ -0,0 +1 @@
+{"root":["./src/main.ts","./src/api/completion.ts","./src/types/completion.ts","./src/app.vue","./src/components/monacoeditor.vue","./src/components/themetoggle.vue","./env.d.ts"],"version":"5.7.3"}
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -0,0 +1,7 @@
+{
+  "files": [],
+  "references": [
+    { "path": "./tsconfig.app.json" },
+    { "path": "./tsconfig.node.json" }
+  ]
+}
--- a/tsconfig.node.json
+++ b/tsconfig.node.json
@@ -0,0 +1,19 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "lib": ["ES2023"],
+    "module": "ESNext",
+    "skipLibCheck": true,
+    "moduleResolution": "bundler",
+    "allowImportingTsExtensions": true,
+    "isolatedModules": true,
+    "moduleDetection": "force",
+    "noEmit": true,
+    "strict": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    "noFallthroughCasesInSwitch": true,
+    "noUncheckedSideEffectImports": true
+  },
+  "include": ["vite.config.ts"]
+}
--- a/tsconfig.node.tsbuildinfo
+++ b/tsconfig.node.tsbuildinfo
@@ -0,0 +1 @@
+{"root":["./vite.config.ts"],"version":"5.7.3"}
--- a/vite.config.ts
+++ b/vite.config.ts
@@ -0,0 +1,19 @@
+import { defineConfig } from 'vite'
+import vue from '@vitejs/plugin-vue'
+
+export default defineConfig({
+  plugins: [vue()],
+  server: {
+    proxy: {
+      '/api': {
+        target: 'http://127.0.0.1:8080',
+        changeOrigin: true,
+      },
+      '/ws': {
+        target: 'ws://127.0.0.1:8080',
+        ws: true,
+        changeOrigin: true,
+      },
+    },
+  },
+})
				`@@ -0,0 +1 @@`
				`{"root":["./src/main.ts","./src/api/completion.ts","./src/types/completion.ts","./src/app.vue","./src/components/monacoeditor.vue","./src/components/themetoggle.vue","./env.d.ts"],"version":"5.7.3"}`
				`@@ -0,0 +1 @@`
				`{"root":["./vite.config.ts"],"version":"5.7.3"}`