Initial commit: Cyrene Plugins SDK + Plugin Manager

Extracted from Cyrene main repo (backend/pkg/plugins + backend/plugin-manager).
Contains SDK interfaces (Plugin/Tool/HostAPI), 13 built-in plugins,
ToolRegistry with call log ring buffer, and Plugin Manager REST API service.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

datetime/plugin.go

@@ -0,0 +1,170 @@
+package datetime
+
+import (
+	"context"
+	"fmt"
+	"strings"
+	"time"
+
+	"git.yeij.top/AskaEth/Cyrene-Plugins/sdk"
+)
+
+type DatetimePlugin struct{ sdk.BasePlugin }
+
+func (p *DatetimePlugin) Metadata() sdk.PluginMetadata {
+	return sdk.PluginMetadata{
+		Name: "datetime", DisplayName: "Date & Time", Version: "1.0.0",
+		Description: "Date/time utilities: now, format, arithmetic, diff, timezone list",
+		Category: "utility", Author: sdk.PluginAuthor{Name: "Cyrene Team"},
+	}
+}
+
+func (p *DatetimePlugin) Tools() []sdk.Tool { return []sdk.Tool{&DatetimeTool{}} }
+
+type DatetimeTool struct{ sdk.BaseTool }
+
+func (t *DatetimeTool) Definition() sdk.ToolDefinition {
+	return sdk.ToolDefinition{
+		ID: "datetime", Name: "datetime", DisplayName: "Date & Time",
+		Description: "Date/time utility. Get current time, format dates, date arithmetic, date diff, list timezones.",
+		Category: "utility", Complexity: sdk.ComplexitySimple,
+		Parameters: map[string]interface{}{
+			"type": "object",
+			"properties": map[string]interface{}{
+				"action":   map[string]interface{}{"type": "string", "enum": []string{"now", "format", "add", "diff", "timezone_list"}},
+				"format":   map[string]interface{}{"type": "string"},
+				"timezone": map[string]interface{}{"type": "string"},
+				"date":     map[string]interface{}{"type": "string"},
+				"duration": map[string]interface{}{"type": "string"},
+				"date2":    map[string]interface{}{"type": "string"},
+			},
+			"required": []string{"action"},
+		},
+	}
+}
+
+func (t *DatetimeTool) Validate(args map[string]interface{}) error {
+	if _, ok := args["action"]; !ok {
+		return fmt.Errorf("missing required parameter: action")
+	}
+	return nil
+}
+
+func (t *DatetimeTool) Execute(_ context.Context, args map[string]interface{}) (*sdk.ToolResult, error) {
+	action, _ := args["action"].(string)
+	tzStr, _ := args["timezone"].(string)
+	loc, _ := parseLocation(tzStr)
+	now := time.Now().In(loc)
+
+	switch action {
+	case "now":
+		return &sdk.ToolResult{ToolName: "datetime", Success: true,
+			Output: fmt.Sprintf("Current time: %s (unix: %d, zone: %s)", now.Format(time.RFC3339), now.Unix(), loc.String())}, nil
+
+	case "format":
+		dateStr, _ := args["date"].(string)
+		format, _ := args["format"].(string)
+		if format == "" {
+			format = time.RFC3339
+		}
+		parsed, err := parseDate(dateStr, loc)
+		if err != nil {
+			return &sdk.ToolResult{ToolName: "datetime", Success: false, Error: err.Error()}, nil
+		}
+		return &sdk.ToolResult{ToolName: "datetime", Success: true,
+			Output: fmt.Sprintf("Formatted: %s", parsed.Format(format))}, nil
+
+	case "add":
+		dateStr, _ := args["date"].(string)
+		durStr, _ := args["duration"].(string)
+		base := now
+		if dateStr != "" {
+			var err error
+			base, err = parseDate(dateStr, loc)
+			if err != nil {
+				return &sdk.ToolResult{ToolName: "datetime", Success: false, Error: err.Error()}, nil
+			}
+		}
+		result, err := addDuration(base, durStr)
+		if err != nil {
+			return &sdk.ToolResult{ToolName: "datetime", Success: false, Error: err.Error()}, nil
+		}
+		return &sdk.ToolResult{ToolName: "datetime", Success: true,
+			Output: fmt.Sprintf("%s + %s = %s", base.Format(time.RFC3339), durStr, result.Format(time.RFC3339))}, nil
+
+	case "diff":
+		d1, _ := args["date"].(string)
+		d2, _ := args["date2"].(string)
+		t1, err := parseDate(d1, loc)
+		if err != nil {
+			return &sdk.ToolResult{ToolName: "datetime", Success: false, Error: err.Error()}, nil
+		}
+		t2, err := parseDate(d2, loc)
+		if err != nil {
+			return &sdk.ToolResult{ToolName: "datetime", Success: false, Error: err.Error()}, nil
+		}
+		diff := t2.Sub(t1)
+		if diff < 0 {
+			diff = -diff
+		}
+		days := int(diff.Hours()) / 24
+		hours := int(diff.Hours()) % 24
+		minutes := int(diff.Minutes()) % 60
+		seconds := int(diff.Seconds()) % 60
+		return &sdk.ToolResult{ToolName: "datetime", Success: true,
+			Output: fmt.Sprintf("Difference: %d days, %d hours, %d minutes, %d seconds", days, hours, minutes, seconds)}, nil
+
+	case "timezone_list":
+		return &sdk.ToolResult{ToolName: "datetime", Success: true,
+			Output: "Common timezones: UTC, Asia/Shanghai, Asia/Tokyo, Asia/Seoul, Asia/Singapore, Asia/Kolkata, Asia/Dubai, Europe/London, Europe/Paris, Europe/Moscow, America/New_York, America/Chicago, America/Los_Angeles, America/Sao_Paulo, Australia/Sydney, Pacific/Auckland, Africa/Cairo, Africa/Lagos"}, nil
+
+	default:
+		return &sdk.ToolResult{ToolName: "datetime", Success: false,
+			Error: fmt.Sprintf("unknown action: %s", action)}, nil
+	}
+}
+
+func parseLocation(tz string) (*time.Location, error) {
+	if tz == "" {
+		loc, err := time.LoadLocation("Asia/Shanghai")
+		if err != nil {
+			return time.UTC, nil
+		}
+		return loc, nil
+	}
+	return time.LoadLocation(tz)
+}
+
+func parseDate(s string, loc *time.Location) (time.Time, error) {
+	formats := []string{time.RFC3339, "2006-01-02T15:04:05", "2006-01-02 15:04:05", "2006-01-02", "2006/01/02"}
+	for _, f := range formats {
+		if t, err := time.ParseInLocation(f, s, loc); err == nil {
+			return t, nil
+		}
+	}
+	return time.Time{}, fmt.Errorf("cannot parse date: %s", s)
+}
+
+func addDuration(t time.Time, durStr string) (time.Time, error) {
+	durStr = strings.TrimSpace(durStr)
+	if durStr == "" {
+		return t, nil
+	}
+	// Handle months and years
+	if strings.Contains(durStr, "M") || strings.Contains(durStr, "y") {
+		months := 0
+		years := 0
+		if strings.Contains(durStr, "y") {
+			fmt.Sscanf(durStr, "%dy", &years)
+		}
+		if strings.Contains(durStr, "M") {
+			fmt.Sscanf(durStr, "%dM", &months)
+		}
+		return t.AddDate(years, months, 0), nil
+	}
+	d, err := time.ParseDuration(durStr)
+	if err != nil {
+		return t, fmt.Errorf("invalid duration: %s", durStr)
+	}
+	return t.Add(d), nil
+}