import type { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js'
import type { AnyNodeId } from '@pascal-app/core/schema'
import { WallNode } from '@pascal-app/core/schema'
import { z } from 'zod'
import type { SceneOperations } from '../operations'
import { ErrorCode, throwMcpError } from './errors'
import { publishLiveSceneSnapshot } from './live-sync'
import { NodeIdSchema, Vec2Schema } from './schemas'

export const createWallInput = {
  levelId: NodeIdSchema,
  start: Vec2Schema,
  end: Vec2Schema,
  thickness: z.number().positive().optional(),
  height: z.number().positive().optional(),
}

export const createWallOutput = {
  wallId: z.string(),
}

export function registerCreateWall(server: McpServer, bridge: SceneOperations): void {
  server.registerTool(
    'create_wall',
    {
      title: 'Create wall',
      description:
        'Create a new wall on the given level between two 2D points. Thickness and height default to the core library defaults when omitted.',
      inputSchema: createWallInput,
      outputSchema: createWallOutput,
    },
    async ({ levelId, start, end, thickness, height }) => {
      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`,
        )
      }
      if (
        typeof parent.metadata === 'object' &&
        parent.metadata !== null &&
        'role' in parent.metadata &&
        parent.metadata.role === 'roof'
      ) {
        throwMcpError(
          ErrorCode.InvalidParams,
          `Roof support level ${levelId} is not an occupied story; create walls on an occupied level instead`,
        )
      }

      const wall = WallNode.parse({
        start: start as [number, number],
        end: end as [number, number],
        ...(thickness !== undefined ? { thickness } : {}),
        ...(height !== undefined ? { height } : {}),
      })
      const id = bridge.createNode(wall, levelId as AnyNodeId)
      await publishLiveSceneSnapshot(bridge, 'create_wall')
      const payload = { wallId: id as string }
      return {
        content: [{ type: 'text' as const, text: JSON.stringify(payload) }],
        structuredContent: payload,
      }
    },
  )
}