lsp/config: make completion trigger characters configurable

- Add trigger_characters to JSON config and ServerOptions
- Store on server and advertise in initialize
- Update README and example config
- Preserve previous defaults when unset

2 files changed, 134 insertions, 116 deletions

diff --git a/internal/llm/ollama.go b/internal/llm/ollama.go
index db3e06b..e8b75c9 100644
--- a/internal/llm/ollama.go
+++ b/internal/llm/ollama.go
@@ -1,115 +1,133 @@
 package llm
 
 import (
-    "bytes"
-    "context"
-    "encoding/json"
-    "errors"
-    "fmt"
-    "net/http"
-    "strings"
-    "time"
+	"bytes"
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+	"strings"
+	"time"
 
-    "hexai/internal/logging"
+	"hexai/internal/logging"
 )
 
 // ollamaClient implements Client against a local Ollama server.
 type ollamaClient struct {
-    httpClient   *http.Client
-    baseURL      string
-    defaultModel string
+	httpClient   *http.Client
+	baseURL      string
+	defaultModel string
 }
 
 func newOllama(baseURL, model string) Client {
-    if strings.TrimSpace(baseURL) == "" {
-        baseURL = "http://localhost:11434"
-    }
-    if strings.TrimSpace(model) == "" {
-        model = "qwen2.5-coder:latest"
-    }
-    return &ollamaClient{
-        httpClient:   &http.Client{Timeout: 30 * time.Second},
-        baseURL:      strings.TrimRight(baseURL, "/"),
-        defaultModel: model,
-    }
+	if strings.TrimSpace(baseURL) == "" {
+		baseURL = "http://localhost:11434"
+	}
+	if strings.TrimSpace(model) == "" {
+		model = "qwen2.5-coder:latest"
+	}
+	return &ollamaClient{
+		httpClient:   &http.Client{Timeout: 30 * time.Second},
+		baseURL:      strings.TrimRight(baseURL, "/"),
+		defaultModel: model,
+	}
 }
 
 type ollamaChatRequest struct {
-    Model   string      `json:"model"`
-    Messages []oaMessage `json:"messages"`
-    Stream  bool        `json:"stream"`
-    Options any         `json:"options,omitempty"`
+	Model    string      `json:"model"`
+	Messages []oaMessage `json:"messages"`
+	Stream   bool        `json:"stream"`
+	Options  any         `json:"options,omitempty"`
 }
 
 type ollamaChatResponse struct {
-    Message struct {
-        Role    string `json:"role"`
-        Content string `json:"content"`
-    } `json:"message"`
-    Done  bool   `json:"done"`
-    Error string `json:"error,omitempty"`
+	Message struct {
+		Role    string `json:"role"`
+		Content string `json:"content"`
+	} `json:"message"`
+	Done  bool   `json:"done"`
+	Error string `json:"error,omitempty"`
 }
 
 func (c *ollamaClient) Chat(ctx context.Context, messages []Message, opts ...RequestOption) (string, error) {
-    o := Options{Model: c.defaultModel}
-    for _, opt := range opts { opt(&o) }
-    if o.Model == "" { o.Model = c.defaultModel }
+	o := Options{Model: c.defaultModel}
+	for _, opt := range opts {
+		opt(&o)
+	}
+	if o.Model == "" {
+		o.Model = c.defaultModel
+	}
 
-    start := time.Now()
-    logging.Logf("llm/ollama ", "chat start model=%s temp=%.2f max_tokens=%d stop=%d messages=%d", o.Model, o.Temperature, o.MaxTokens, len(o.Stop), len(messages))
-    for i, m := range messages {
-        logging.Logf("llm/ollama ", "msg[%d] role=%s size=%d preview=%s%s%s", i, m.Role, len(m.Content), logging.AnsiCyan, logging.PreviewForLog(m.Content), logging.AnsiBase)
-    }
+	start := time.Now()
+	logging.Logf("llm/ollama ", "chat start model=%s temp=%.2f max_tokens=%d stop=%d messages=%d", o.Model, o.Temperature, o.MaxTokens, len(o.Stop), len(messages))
+	for i, m := range messages {
+		logging.Logf("llm/ollama ", "msg[%d] role=%s size=%d preview=%s%s%s", i, m.Role, len(m.Content), logging.AnsiCyan, logging.PreviewForLog(m.Content), logging.AnsiBase)
+	}
 
-    req := ollamaChatRequest{Model: o.Model, Stream: false}
-    req.Messages = make([]oaMessage, len(messages))
-    for i, m := range messages { req.Messages[i] = oaMessage{Role: m.Role, Content: m.Content} }
+	req := ollamaChatRequest{Model: o.Model, Stream: false}
+	req.Messages = make([]oaMessage, len(messages))
+	for i, m := range messages {
+		req.Messages[i] = oaMessage{Role: m.Role, Content: m.Content}
+	}
 
-    // Build options map only if any option is set
-    optsMap := map[string]any{}
-    if o.Temperature != 0 { optsMap["temperature"] = o.Temperature }
-    if o.MaxTokens > 0 { optsMap["num_predict"] = o.MaxTokens }
-    if len(o.Stop) > 0 { optsMap["stop"] = o.Stop }
-    if len(optsMap) > 0 { req.Options = optsMap }
+	// Build options map only if any option is set
+	optsMap := map[string]any{}
+	if o.Temperature != 0 {
+		optsMap["temperature"] = o.Temperature
+	}
+	if o.MaxTokens > 0 {
+		optsMap["num_predict"] = o.MaxTokens
+	}
+	if len(o.Stop) > 0 {
+		optsMap["stop"] = o.Stop
+	}
+	if len(optsMap) > 0 {
+		req.Options = optsMap
+	}
 
-    body, err := json.Marshal(req)
-    if err != nil { return "", err }
+	body, err := json.Marshal(req)
+	if err != nil {
+		return "", err
+	}
 
-    endpoint := c.baseURL + "/api/chat"
-    logging.Logf("llm/ollama ", "POST %s", endpoint)
-    httpReq, err := http.NewRequestWithContext(ctx, http.MethodPost, endpoint, bytes.NewReader(body))
-    if err != nil { return "", err }
-    httpReq.Header.Set("Content-Type", "application/json")
+	endpoint := c.baseURL + "/api/chat"
+	logging.Logf("llm/ollama ", "POST %s", endpoint)
+	httpReq, err := http.NewRequestWithContext(ctx, http.MethodPost, endpoint, bytes.NewReader(body))
+	if err != nil {
+		return "", err
+	}
+	httpReq.Header.Set("Content-Type", "application/json")
 
-    resp, err := c.httpClient.Do(httpReq)
-    if err != nil {
-        logging.Logf("llm/ollama ", "%shttp error after %s: %v%s", logging.AnsiRed, time.Since(start), err, logging.AnsiBase)
-        return "", err
-    }
-    defer resp.Body.Close()
-    if resp.StatusCode < 200 || resp.StatusCode >= 300 {
-        var apiErr ollamaChatResponse
-        _ = json.NewDecoder(resp.Body).Decode(&apiErr)
-        if strings.TrimSpace(apiErr.Error) != "" {
-            logging.Logf("llm/ollama ", "%sapi error status=%d msg=%s duration=%s%s", logging.AnsiRed, resp.StatusCode, apiErr.Error, time.Since(start), logging.AnsiBase)
-            return "", fmt.Errorf("ollama error: %s (status %d)", apiErr.Error, resp.StatusCode)
-        }
-        logging.Logf("llm/ollama ", "%shttp non-2xx status=%d duration=%s%s", logging.AnsiRed, resp.StatusCode, time.Since(start), logging.AnsiBase)
-        return "", fmt.Errorf("ollama http error: status %d", resp.StatusCode)
-    }
+	resp, err := c.httpClient.Do(httpReq)
+	if err != nil {
+		logging.Logf("llm/ollama ", "%shttp error after %s: %v%s", logging.AnsiRed, time.Since(start), err, logging.AnsiBase)
+		return "", err
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		var apiErr ollamaChatResponse
+		_ = json.NewDecoder(resp.Body).Decode(&apiErr)
+		if strings.TrimSpace(apiErr.Error) != "" {
+			logging.Logf("llm/ollama ", "%sapi error status=%d msg=%s duration=%s%s", logging.AnsiRed, resp.StatusCode, apiErr.Error, time.Since(start), logging.AnsiBase)
+			return "", fmt.Errorf("ollama error: %s (status %d)", apiErr.Error, resp.StatusCode)
+		}
+		logging.Logf("llm/ollama ", "%shttp non-2xx status=%d duration=%s%s", logging.AnsiRed, resp.StatusCode, time.Since(start), logging.AnsiBase)
+		return "", fmt.Errorf("ollama http error: status %d", resp.StatusCode)
+	}
 
-    var out ollamaChatResponse
-    if err := json.NewDecoder(resp.Body).Decode(&out); err != nil {
-        logging.Logf("llm/ollama ", "%sdecode error after %s: %v%s", logging.AnsiRed, time.Since(start), err, logging.AnsiBase)
-        return "", err
-    }
-    if strings.TrimSpace(out.Message.Content) == "" {
-        logging.Logf("llm/ollama ", "%sempty content returned duration=%s%s", logging.AnsiRed, time.Since(start), logging.AnsiBase)
-        return "", errors.New("ollama: empty content")
-    }
-    content := out.Message.Content
-    logging.Logf("llm/ollama ", "success size=%d preview=%s%s%s duration=%s", len(content), logging.AnsiGreen, logging.PreviewForLog(content), logging.AnsiBase, time.Since(start))
-    return content, nil
+	var out ollamaChatResponse
+	if err := json.NewDecoder(resp.Body).Decode(&out); err != nil {
+		logging.Logf("llm/ollama ", "%sdecode error after %s: %v%s", logging.AnsiRed, time.Since(start), err, logging.AnsiBase)
+		return "", err
+	}
+	if strings.TrimSpace(out.Message.Content) == "" {
+		logging.Logf("llm/ollama ", "%sempty content returned duration=%s%s", logging.AnsiRed, time.Since(start), logging.AnsiBase)
+		return "", errors.New("ollama: empty content")
+	}
+	content := out.Message.Content
+	logging.Logf("llm/ollama ", "success size=%d preview=%s%s%s duration=%s", len(content), logging.AnsiGreen, logging.PreviewForLog(content), logging.AnsiBase, time.Since(start))
+	return content, nil
 }
 
 // Provider metadata
diff --git a/internal/llm/provider.go b/internal/llm/provider.go
index c7367ed..6c6cf04 100644
--- a/internal/llm/provider.go
+++ b/internal/llm/provider.go
@@ -1,9 +1,9 @@
 package llm
 
 import (
-    "context"
-    "errors"
-    "strings"
+	"context"
+	"errors"
+	"strings"
 )
 
 // Message represents a chat-style prompt message.
@@ -15,12 +15,12 @@ type Message struct {
 // Client is a minimal LLM provider interface.
 // Future providers (Ollama, etc.) should implement this.
 type Client interface {
-    // Chat sends chat messages and returns the assistant text.
-    Chat(ctx context.Context, messages []Message, opts ...RequestOption) (string, error)
-    // Name returns the provider's short name (e.g., "openai", "ollama").
-    Name() string
-    // DefaultModel returns the configured default model name.
-    DefaultModel() string
+	// Chat sends chat messages and returns the assistant text.
+	Chat(ctx context.Context, messages []Message, opts ...RequestOption) (string, error)
+	// Name returns the provider's short name (e.g., "openai", "ollama").
+	Name() string
+	// DefaultModel returns the configured default model name.
+	DefaultModel() string
 }
 
 // Options for a request. Providers may ignore unsupported fields.
@@ -43,32 +43,32 @@ func WithStop(stop ...string) RequestOption {
 
 // Config defines provider configuration read from the Hexai config file.
 type Config struct {
-    Provider       string
-    // OpenAI options
-    OpenAIBaseURL  string
-    OpenAIModel    string
-    // Ollama options
-    OllamaBaseURL  string
-    OllamaModel    string
+	Provider string
+	// OpenAI options
+	OpenAIBaseURL string
+	OpenAIModel   string
+	// Ollama options
+	OllamaBaseURL string
+	OllamaModel   string
 }
 
 // NewFromConfig creates an LLM client using only the supplied configuration.
 // The OpenAI API key is supplied separately and may be read from the environment
 // by the caller; other environment-based configuration is not used.
 func NewFromConfig(cfg Config, openAIAPIKey string) (Client, error) {
-    p := strings.ToLower(strings.TrimSpace(cfg.Provider))
-    if p == "" {
-        p = "openai"
-    }
-    switch p {
-    case "openai":
-        if strings.TrimSpace(openAIAPIKey) == "" {
-            return nil, errors.New("missing OPENAI_API_KEY for provider openai")
-        }
-        return newOpenAI(cfg.OpenAIBaseURL, cfg.OpenAIModel, openAIAPIKey), nil
-    case "ollama":
-        return newOllama(cfg.OllamaBaseURL, cfg.OllamaModel), nil
-    default:
-        return nil, errors.New("unknown LLM provider: " + p)
-    }
+	p := strings.ToLower(strings.TrimSpace(cfg.Provider))
+	if p == "" {
+		p = "openai"
+	}
+	switch p {
+	case "openai":
+		if strings.TrimSpace(openAIAPIKey) == "" {
+			return nil, errors.New("missing OPENAI_API_KEY for provider openai")
+		}
+		return newOpenAI(cfg.OpenAIBaseURL, cfg.OpenAIModel, openAIAPIKey), nil
+	case "ollama":
+		return newOllama(cfg.OllamaBaseURL, cfg.OllamaModel), nil
+	default:
+		return nil, errors.New("unknown LLM provider: " + p)
+	}
 }