Switch to Anthropic SDK because we need MCP servers

anthropic.go

@@ -0,0 +1,175 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net/http"
+	"strings"
+	"time"
+
+	"github.com/anthropics/anthropic-sdk-go"
+	"github.com/anthropics/anthropic-sdk-go/packages/param"
+)
+
+// ErrModelNotFound is returned when the configured Anthropic model is no longer available
+// (deprecated or removed). Callers can use errors.Is to detect this and surface an
+// actionable message to admins/owners while keeping the response vague for regular users.
+var ErrModelNotFound = errors.New("model not found or deprecated")
+
+func (b *Bot) getAnthropicResponse(ctx context.Context, messages []anthropic.BetaMessageParam, isNewChat, isOwner, isEmojiOnly bool, username string, firstName string, lastName string, isPremium bool, languageCode string, messageTime int) (string, error) {
+	// Use prompts from config
+	var systemMessage string
+	if isNewChat {
+		systemMessage = b.config.SystemPrompts["new_chat"]
+	} else {
+		systemMessage = b.config.SystemPrompts["continue_conversation"]
+	}
+
+	// Combine default prompt with custom instructions
+	systemMessage = b.config.SystemPrompts["default"] + " " + b.config.SystemPrompts["custom_instructions"] + " " + systemMessage
+
+	// Handle username placeholder
+	usernameValue := username
+	if username == "" {
+		usernameValue = "unknown" // Use "unknown" when username is not available
+	}
+	systemMessage = strings.ReplaceAll(systemMessage, "{username}", usernameValue)
+
+	// Handle firstname placeholder
+	firstnameValue := firstName
+	if firstName == "" {
+		firstnameValue = "unknown" // Use "unknown" when first name is not available
+	}
+	systemMessage = strings.ReplaceAll(systemMessage, "{firstname}", firstnameValue)
+
+	// Handle lastname placeholder
+	lastnameValue := lastName
+	if lastName == "" {
+		lastnameValue = "" // Empty string when last name is not available
+	}
+	systemMessage = strings.ReplaceAll(systemMessage, "{lastname}", lastnameValue)
+
+	// Handle language code placeholder
+	langValue := languageCode
+	if languageCode == "" {
+		langValue = "en" // Default to English when language code is not available
+	}
+	systemMessage = strings.ReplaceAll(systemMessage, "{language}", langValue)
+
+	// Handle premium status
+	premiumStatus := "regular user"
+	if isPremium {
+		premiumStatus = "premium user"
+	}
+	systemMessage = strings.ReplaceAll(systemMessage, "{premium_status}", premiumStatus)
+
+	// Handle time awareness
+	timeObj := time.Unix(int64(messageTime), 0)
+	hour := timeObj.Hour()
+	var timeContext string
+	if hour >= 5 && hour < 12 {
+		timeContext = "morning"
+	} else if hour >= 12 && hour < 18 {
+		timeContext = "afternoon"
+	} else if hour >= 18 && hour < 22 {
+		timeContext = "evening"
+	} else {
+		timeContext = "night"
+	}
+	systemMessage = strings.ReplaceAll(systemMessage, "{time_context}", timeContext)
+
+	if !isOwner {
+		systemMessage += " " + b.config.SystemPrompts["avoid_sensitive"]
+	}
+
+	if isEmojiOnly {
+		systemMessage += " " + b.config.SystemPrompts["respond_with_emojis"]
+	}
+
+	// Debug logging
+	InfoLogger.Printf("Sending %d messages to Anthropic", len(messages))
+
+	params := anthropic.BetaMessageNewParams{
+		Model:     b.config.Model,
+		MaxTokens: 1000,
+		Messages:  messages,
+		System:    []anthropic.BetaTextBlockParam{{Text: systemMessage}},
+	}
+
+	// Apply temperature if set in config
+	if b.config.Temperature != nil {
+		params.Temperature = param.NewOpt(float64(*b.config.Temperature))
+	}
+
+	// MCP servers + matching toolset entries. The mcp-client-2025-11-20 beta
+	// requires per-tool filtering on the toolset (Configs + DefaultConfig),
+	// NOT the deprecated per-server tool_configuration block.
+	if len(b.config.MCPServers) > 0 {
+		mcpServers := make([]anthropic.BetaRequestMCPServerURLDefinitionParam, 0, len(b.config.MCPServers))
+		tools := make([]anthropic.BetaToolUnionParam, 0, len(b.config.MCPServers))
+		for _, s := range b.config.MCPServers {
+			srv := anthropic.BetaRequestMCPServerURLDefinitionParam{
+				Name: s.Name,
+				URL:  s.URL,
+			}
+			if s.AuthorizationToken != "" {
+				srv.AuthorizationToken = param.NewOpt(s.AuthorizationToken)
+			}
+			mcpServers = append(mcpServers, srv)
+
+			toolset := &anthropic.BetaMCPToolsetParam{
+				MCPServerName: s.Name,
+			}
+			if len(s.AllowedTools) > 0 {
+				toolset.DefaultConfig = anthropic.BetaMCPToolDefaultConfigParam{
+					Enabled: param.NewOpt(false),
+				}
+				toolset.Configs = make(map[string]anthropic.BetaMCPToolConfigParam, len(s.AllowedTools))
+				for _, tool := range s.AllowedTools {
+					toolset.Configs[tool] = anthropic.BetaMCPToolConfigParam{
+						Enabled: param.NewOpt(true),
+					}
+				}
+			}
+			tools = append(tools, anthropic.BetaToolUnionParam{OfMCPToolset: toolset})
+		}
+		params.MCPServers = mcpServers
+		params.Tools = tools
+		params.Betas = []anthropic.AnthropicBeta{anthropic.AnthropicBetaMCPClient2025_11_20}
+	}
+
+	resp, err := b.anthropicClient.Beta.Messages.New(ctx, params)
+	if err != nil {
+		var apiErr *anthropic.Error
+		if errors.As(err, &apiErr) && apiErr.StatusCode == http.StatusNotFound {
+			return "", fmt.Errorf("%w: %s", ErrModelNotFound, b.config.Model)
+		}
+		return "", fmt.Errorf("error creating Anthropic message: %w", err)
+	}
+
+	var sb strings.Builder
+	for _, block := range resp.Content {
+		switch block.Type {
+		case "text":
+			sb.WriteString(block.Text)
+		case "mcp_tool_use":
+			InfoLogger.Printf("[mcp] tool_use server=%q name=%q id=%q input=%s",
+				block.ServerName, block.Name, block.ID, string(block.Input))
+		case "mcp_tool_result":
+			preview := block.JSON.Content.Raw()
+			if len(preview) > 500 {
+				preview = preview[:500] + "...(truncated)"
+			}
+			InfoLogger.Printf("[mcp] tool_result tool_use_id=%q server=%q is_error=%v content=%s",
+				block.ToolUseID, block.ServerName, block.IsError, preview)
+		default:
+			InfoLogger.Printf("[mcp] block type=%q (unhandled)", block.Type)
+		}
+	}
+	out := sb.String()
+	if out == "" {
+		return "", fmt.Errorf("unexpected response format from Anthropic")
+	}
+	return out, nil
+}