// opsxdb-mcp：stdio MCP Server，暴露只读数据库工具（P0）。 // Logan.Li
//
// 配置：
//   ~/.opsxdb/mcp.json          — allowed_connection_ids；mode（P0 执行层强制只读）
//   ~/.opsxdb/connections.json  — 桌面双写的连接列表（密码 ox1. 混淆）
//   ~/.opsxdb/logs/mcp-audit.jsonl
//
// Cursor 示例见 docs/mcp-cursor.example.json
package main

import (
	"context"
	"encoding/json"
	"fmt"
	"os"

	"github.com/mark3labs/mcp-go/mcp"
	"github.com/mark3labs/mcp-go/server"

	"opsxdb/server/internal/aitools"
)

func main() {
	rt, err := aitools.DefaultRuntime()
	if err != nil {
		fmt.Fprintf(os.Stderr, "opsxdb-mcp: load policy: %v\n", err)
		os.Exit(1)
	}

	s := server.NewMCPServer(
		"opsxdb",
		"0.1.0",
		server.WithToolCapabilities(true),
	)

	register := func(name, desc string, props map[string]any, required []string) {
		schema := map[string]any{
			"type":       "object",
			"properties": props,
		}
		if len(required) > 0 {
			schema["required"] = required
		}
		raw, _ := json.Marshal(schema)
		t := mcp.NewToolWithRawSchema(name, desc, raw)
		toolName := name
		s.AddTool(t, func(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallToolResult, error) {
			args := req.GetArguments()
			out, err := rt.Call(ctx, toolName, args)
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			return mcp.NewToolResultText(aitools.ResultJSON(out)), nil
		})
	}

	connID := map[string]any{"type": "string", "description": "Saved connection id from opsxdb_list_connections"}
	database := map[string]any{"type": "string", "description": "Database / schema / Redis DB index"}

	register(aitools.ToolListConnections,
		"List whitelisted OpsxDB connections (id/name/driver/host/port/database; never passwords).",
		map[string]any{}, nil)

	register(aitools.ToolListDatabases,
		"List databases for a connection.",
		map[string]any{"connection_id": connID}, []string{"connection_id"})

	register(aitools.ToolListTables,
		"List tables/views (or engine equivalents) in a database.",
		map[string]any{"connection_id": connID, "database": database}, []string{"connection_id"})

	register(aitools.ToolDescribeTable,
		"Describe columns and metadata for a table.",
		map[string]any{
			"connection_id": connID,
			"database":      database,
			"table":         map[string]any{"type": "string", "description": "Table name"},
		}, []string{"connection_id", "table"})

	register(aitools.ToolGetSchemaContext,
		"Compact schema text for LLM context (capped ~4k chars).",
		map[string]any{
			"connection_id": connID,
			"database":      database,
			"max_tables":    map[string]any{"type": "integer", "description": "Max tables to include (default 40)"},
		}, []string{"connection_id"})

	register(aitools.ToolExecuteQuery,
		"Execute a READ-ONLY SQL query (SELECT/SHOW/EXPLAIN/WITH…SELECT). Writes and DDL are rejected in P0. Default limit 100, max 500.",
		map[string]any{
			"connection_id": connID,
			"sql":           map[string]any{"type": "string", "description": "Read-only SQL"},
			"database":      database,
			"limit":         map[string]any{"type": "integer", "description": "Row limit (default 100, max 500)"},
		}, []string{"connection_id", "sql"})

	register(aitools.ToolExecuteRedisCommand,
		"Execute a READ-ONLY Redis command (GET/SCAN/TYPE/TTL/…). FLUSH*/KEYS and writes are rejected in P0.",
		map[string]any{
			"connection_id": connID,
			"command":       map[string]any{"type": "string", "description": "Single Redis command line"},
			"database":      database,
		}, []string{"connection_id", "command"})

	if err := server.ServeStdio(s); err != nil {
		fmt.Fprintf(os.Stderr, "opsxdb-mcp: %v\n", err)
		os.Exit(1)
	}
}