import type { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js'
import type { AnyNodeId } from '@pascal-app/core/schema'
import { ZoneNode } from '@pascal-app/core/schema'
import { z } from 'zod'
import type { SceneBridge } from '../bridge/scene-bridge'
import { ErrorCode, throwMcpError } from './errors'
import { NodeIdSchema, Vec2Schema } from './schemas'

export const setZoneInput = {
  levelId: NodeIdSchema,
  polygon: z.array(Vec2Schema).min(3),
  label: z.string().min(1),
  properties: z.record(z.string(), z.unknown()).optional(),
}

export const setZoneOutput = {
  zoneId: z.string(),
}

export function registerSetZone(server: McpServer, bridge: SceneBridge): void {
  server.registerTool(
    'set_zone',
    {
      title: 'Set zone',
      description:
        'Create a polygonal zone on the given level. label is stored as the zone name and properties are merged into metadata.',
      inputSchema: setZoneInput,
      outputSchema: setZoneOutput,
    },
    async ({ levelId, polygon, label, properties }) => {
      const parent = bridge.getNode(levelId as AnyNodeId)
      if (!parent) {
        throwMcpError(ErrorCode.InvalidParams, `Level not found: ${levelId}`)
      }
      if (parent.type !== 'level') {
        throwMcpError(
          ErrorCode.InvalidParams,
          `Node ${levelId} is a ${parent.type}, expected level`,
        )
      }

      const zone = ZoneNode.parse({
        name: label,
        polygon: polygon as Array<[number, number]>,
        metadata: properties ?? {},
      })
      const id = bridge.createNode(zone, levelId as AnyNodeId)

      const payload = { zoneId: id as string }
      return {
        content: [{ type: 'text' as const, text: JSON.stringify(payload) }],
        structuredContent: payload,
      }
    },
  )
}