noxious_server/src/socketEvents/gameMaster/assetManager/sprite/update.ts

import { Server } from 'socket.io'
import { TSocket } from '../../../../utilities/types'
import prisma from '../../../../utilities/prisma'
import type { Prisma, SpriteAction } from '@prisma/client'
import { writeFile, mkdir } from 'node:fs/promises'
import sharp from 'sharp'
import { getPublicPath } from '../../../../utilities/storage'
import CharacterRepository from '../../../../repositories/characterRepository'
import { gameMasterLogger } from '../../../../utilities/logger'

type SpriteActionInput = Omit<SpriteAction, 'id' | 'spriteId' | 'frameWidth' | 'frameHeight'> & {
  sprites: string[]
}

type Payload = {
  id: string
  name: string
  spriteActions: Prisma.JsonValue
}

interface ProcessedSpriteAction extends SpriteActionInput {
  frameWidth: number
  frameHeight: number
  buffersWithDimensions: Array<{
    buffer: Buffer
    width: number | undefined
    height: number | undefined
  }>
}

export default class SpriteUpdateEvent {
  constructor(
    private readonly io: Server,
    private readonly socket: TSocket
  ) {}

  public listen(): void {
    this.socket.on('gm:sprite:update', this.handleSpriteUpdate.bind(this))
  }

  private async handleSpriteUpdate(data: Payload, callback: (success: boolean) => void): Promise<void> {
    const character = await CharacterRepository.getById(this.socket.characterId!)
    if (character?.role !== 'gm') {
      return callback(false)
    }

    try {
      const parsedSpriteActions = validateSpriteActions(data.spriteActions)
      const processedActions = await processSprites(parsedSpriteActions)

      await updateDatabase(data.id, data.name, processedActions)
      await saveSpritesToDisk(data.id, processedActions)

      callback(true)
    } catch (error) {
      gameMasterLogger.error(`Error updating sprite ${data.id}: ${error instanceof Error ? error.message : String(error)}`)
      callback(false)
    }

    function validateSpriteActions(spriteActions: Prisma.JsonValue): SpriteActionInput[] {
      try {
        const parsed = JSON.parse(JSON.stringify(spriteActions)) as SpriteActionInput[]
        if (!Array.isArray(parsed)) {
          gameMasterLogger.error('Error parsing spriteActions: spriteActions is not an array')
        }
        return parsed
      } catch (error) {
        gameMasterLogger.error(`Error parsing spriteActions: ${error instanceof Error ? error.message : String(error)}`)
        throw error
      }
    }

    async function processSprites(spriteActions: SpriteActionInput[]): Promise<ProcessedSpriteAction[]> {
      return Promise.all(
        spriteActions.map(async (spriteAction) => {
          const { action, sprites } = spriteAction

          if (!Array.isArray(sprites) || sprites.length === 0) {
            gameMasterLogger.error(`Invalid sprites array for action: ${action}`)
          }

          const buffersWithDimensions = await Promise.all(
            sprites.map(async (sprite: string) => {
              const buffer = Buffer.from(sprite.split(',')[1], 'base64')
              const normalizedBuffer = await normalizeSprite(buffer)
              const { width, height } = await sharp(normalizedBuffer).metadata()
              return { buffer: normalizedBuffer, width, height }
            })
          )

          const frameWidth = Math.max(...buffersWithDimensions.map((b) => b.width || 0))
          const frameHeight = Math.max(...buffersWithDimensions.map((b) => b.height || 0))

          return {
            ...spriteAction,
            frameWidth,
            frameHeight,
            buffersWithDimensions
          }
        })
      )
    }

    async function normalizeSprite(buffer: Buffer): Promise<Buffer> {
      const image = sharp(buffer)

      // Remove any transparent edges
      const trimmed = await image
        .trim()
        .toBuffer()

      // Optional: Ensure dimensions are even numbers
      const metadata = await sharp(trimmed).metadata()
      const width = Math.ceil(metadata.width! / 2) * 2
      const height = Math.ceil(metadata.height! / 2) * 2

      return sharp(trimmed)
        .resize(width, height, {
          fit: 'contain',
          background: { r: 0, g: 0, b: 0, alpha: 0 }
        })
        .toBuffer()
    }

    async function saveSpritesToDisk(id: string, processedActions: ProcessedSpriteAction[]) {
      const publicFolder = getPublicPath('sprites', id)
      await mkdir(publicFolder, { recursive: true })

      await Promise.all(
        processedActions.map(async ({ action, buffersWithDimensions, frameWidth, frameHeight }) => {
          // First pass: analyze all frames to determine the consistent dimensions
          const frames = await Promise.all(
            buffersWithDimensions.map(async ({ buffer }) => {
              const image = sharp(buffer)

              // Get trim boundaries to find actual sprite content
              const { info: trimData } = await image
                .trim()
                .toBuffer({ resolveWithObject: true })

              // Get original metadata
              const metadata = await sharp(buffer).metadata()

              return {
                buffer,
                width: metadata.width!,
                height: metadata.height!,
                trimmed: {
                  width: trimData.width,
                  height: trimData.height,
                  left: metadata.width! - trimData.width,
                  top: metadata.height! - trimData.height
                }
              }
            })
          )

          // Calculate the average center point of all frames
          const centerPoints = frames.map(frame => ({
            x: Math.floor(frame.trimmed.left + frame.trimmed.width / 2),
            y: Math.floor(frame.trimmed.top + frame.trimmed.height / 2)
          }))

          const avgCenterX = Math.round(centerPoints.reduce((sum, p) => sum + p.x, 0) / frames.length)
          const avgCenterY = Math.round(centerPoints.reduce((sum, p) => sum + p.y, 0) / frames.length)

          // Create the combined image with precise alignment
          const combinedImage = await sharp({
            create: {
              width: frameWidth * frames.length,
              height: frameHeight,
              channels: 4,
              background: { r: 0, g: 0, b: 0, alpha: 0 }
            }
          })
            .composite(
              frames.map(({ buffer, width, height }, index) => {
                // Calculate offset to maintain consistent center point
                const frameCenterX = Math.floor(width / 2)
                const frameCenterY = Math.floor(height / 2)

                const adjustedLeft = index * frameWidth + (frameWidth / 2) - frameCenterX
                const adjustedTop = (frameHeight / 2) - frameCenterY

                // Round to nearest even number to prevent sub-pixel rendering
                const left = Math.round(adjustedLeft / 2) * 2
                const top = Math.round(adjustedTop / 2) * 2

                return {
                  input: buffer,
                  left,
                  top
                }
              })
            )
            .png()
            .toBuffer()

          const filename = getPublicPath('sprites', id, `${action}.png`)
          await writeFile(filename, combinedImage)
        })
      )
    }

    async function updateDatabase(id: string, name: string, processedActions: ProcessedSpriteAction[]) {
      await prisma.sprite.update({
        where: { id },
        data: {
          name,
          spriteActions: {
            deleteMany: { spriteId: id },
            create: processedActions.map(({ action, sprites, originX, originY, isAnimated, isLooping, frameWidth, frameHeight, frameSpeed }) => ({
              action,
              sprites,
              originX,
              originY,
              isAnimated,
              isLooping,
              frameWidth,
              frameHeight,
              frameSpeed
            }))
          }
        }
      })
    }
  }
}