blockchain-javascript/scripts/lib/factory-lib.js

const logger = require("../../utils/logger")
const BaseModel = require("../../model/base-model");

module.exports = class FactoryLib {
  constructor(web3, chain) {
    this.web3 = web3
    this.chain = chain
    
    this.factoryModel = new BaseModel(this.chain.id, BaseModel.MODULES.FACTORY)

    this.factoryContractMap = {}
    this.positionManagerContractMap = {}

    // abi加载
    this.v2FactoryAbi = require('../../abi/UNIV2_FACTORY_ABI.json')
    this.positionManagerAbi = require('../../abi/UNIV3_POSITION_MANAGER_ABI.json')
  }

  async getFactoryList() {
    const requestRst = await this.factoryModel.find()

    if (requestRst.state) {
      return requestRst.data
    } else {
      logger.error(requestRst.msg)

      return []
    }
  }

  getFactoryContract(factoryAddress) {
    if (!this.factoryContractMap[factoryAddress]) {
      this.factoryContractMap[factoryAddress] = new this.web3.eth.Contract(this.v2FactoryAbi, factoryAddress)
    }

    return this.factoryContractMap[factoryAddress]
  }

  getPositionManager(positionManagerAddress) {
    if (!this.positionManagerContractMap[positionManagerAddress]) {
      this.positionManagerContractMap[positionManagerAddress] = new this.web3.eth.Contract(this.positionManagerAbi, positionManagerAddress)
    }

    return this.positionManagerContractMap[positionManagerAddress]
  }

  async getPositionLength(positionManagerContract, low) {
    let high = 1_000_000

    let checkNumber = low
    let prevLow = low
    let prevHigh = high

    async function check(checkNumber) {
      async function final_check(checkNumber) {
        try {
          await positionManagerContract.methods.positions(checkNumber).call()

          return true
        } catch (e) {
          return false
        }
      }

      // [,,,,,c(,,,,,,,)]
      let too_low = false
      for (let i = 1; i <= 5; i++) {
        too_low = too_low || (await final_check(checkNumber + i))
      }
      if (too_low) return 'too_low'

      // [,,,,,(c,,,,,,,)]
      let too_high = true
      for (let i = 0; i < 5; i++) {
        too_high = too_high && (!await final_check(checkNumber + i))
      }
      if (too_high) return 'too_high'

      return 'ok'
    }

    let count = 60
    while (--count > 0) {
      let checkRst = await check(checkNumber)
      // logger.debug(`[${low}, ${high}], c: ${checkNumber}, ${checkRst}. [${++count}]`)

      if (checkRst === 'ok') {
        break
      } else {
        let tempHigh = high
        let tempLow = low

        if (checkNumber === low) {
          if (checkRst === 'too_high') {
            high = tempLow
            low = prevLow

            prevHigh = tempHigh
            prevLow = tempLow

            checkNumber = high
          } else if (checkRst === 'too_low') {
            low = low + Math.floor((high - low) / 2)

            prevLow = tempLow

            checkNumber = low
          }
        } else if (checkNumber === high) {
          if (checkRst === 'too_high') {
            high = low + Math.floor((high - low) / 2)

            prevHigh = tempHigh

            checkNumber = high
          } else if (checkRst === 'too_low') {
            low = tempHigh
            high = prevHigh

            prevHigh = tempHigh
            prevLow = tempLow

            checkNumber = low
          }
        }
      }
    }

    return checkNumber
  }

  async getPairsLength(factory) {
    if (factory.version === 'univ2') {
      // 获取工厂实例
      const v2Factory = this.getFactoryContract(factory.hash)
      // 获取当前pairsLength
      return await v2Factory.methods.allPairsLength().call()
    } else if (factory.version === 'univ3') {
      // 获取positionManager
      const v3PositionManager = this.getPositionManager(factory.positionManager)
      return await this.getPositionLength(v3PositionManager, 0)
    } else {
      throw Error(`Unknown factory version: ${factory.version}, hash is: ${factory.hash}.`)
    }
  }
}