import { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js'
import { z } from 'zod'
import { getSession } from '../state.js'
/**
* 获取当前场景
* 返回所有元素和应用程序状态
*/
export function registerGetScene(server: McpServer): void {
server.registerTool(
'get_scene',
{
description:
'Retrieve complete information about the current diagram scene.\n\n' +
'Returns:\n' +
'- List of all elements\n' +
'- Application state\n' +
'- Version number\n' +
'- Session ID\n\n' +
'Usage scenarios:\n' +
'- Viewing current diagram content\n' +
'- Analyzing scene structure\n' +
'- Obtaining element IDs for updates/deletion\n\n' +
'Multi-session support: Specify sessionId to query a specific session.',
inputSchema: z.object({
sessionId: z
.string()
.optional()
.describe('Session ID. If not provided, uses default session.'),
}),
},
async ({ sessionId }) => {
try {
const session = getSession(sessionId)
// 过滤掉已删除的元素
const activeElements = session.elements.filter((el) => !el.isDeleted)
// 统计元素类型
const elementTypes = activeElements.reduce(
(acc, el) => {
acc[el.type] = (acc[el.type] || 0) + 1
return acc
},
{} as Record<string, number>,
)
return {
content: [
{
type: 'text',
text:
`📊 Current Scene Information\n` +
`═══════════════════\n\n` +
`Session ID: ${session.id}\n` +
`Version: ${session.version}\n` +
`Last Updated: ${session.lastUpdated.toISOString()}\n` +
`Active Elements: ${activeElements.length}\n` +
`Total Elements: ${session.elements.length}\n\n` +
`Element Types:\n${Object.entries(elementTypes)
.map(([type, count]) => ` • ${type}: ${count}`)
.join('\n')}\n\n` +
`Canvas Background: ${session.appState.viewBackgroundColor}\n\n` +
`Active Elements List:\n${activeElements
.map(
(el) =>
` • [${el.id}] ${el.type} @ (${Math.round(el.x ?? 0)}, ${Math.round(el.y ?? 0)})`,
)
.join('\n')}`,
},
],
}
} catch (error) {
const message = error instanceof Error ? error.message : String(error)
return {
content: [{ type: 'text', text: `Error: ${message}` }],
isError: true,
}
}
},
)
}
