cityssm/node-green-button-parser

const availableFunctionBlocks = Object.freeze({
  1: 'Common',
  2: 'Download My Data',
  3: 'Connect My Data',
  4: 'Interval Metering',
  5: 'Interval Electricity Metering',
  6: 'Demand Electricity Metering',
  7: 'Net Metering',
  8: 'Forward and Reverse Metering',
  9: 'Register Values',
  10: 'Gas',
  11: 'Water',
  12: 'Cost of Interval Data',
  13: 'Security and Privacy Classes',

  /**
   * @deprecated replaced by FB 31
   */
  14: 'Authorization and Authentication',

  15: 'Usage Summary',
  16: 'Usage Summary with Cost',
  17: 'Power Quality Summary',
  18: 'Multiple Usage Points',
  19: 'Partial Update Data',
  27: 'Usage Summary with Demands and Previous Day Attributes',
  28: 'Usage Summary Costs for Current Billing Period',
  29: 'Temperature Interval Metering',
  30: 'Common User Experience (DMD only)',
  31: 'Authorization and Authentication w/o Pre-Negotiated Scope',
  32: 'Resource Level REST',
  33: 'Management REST Services',
  34: 'SFTP for Bulk',
  35: 'REST for Bulk',
  36: 'Third Party Dynamic Registration',
  37: 'Query Parameters',
  38: 'On Demand Requests',
  39: 'PUSH Model',
  40: 'Offline Authorization',
  41: 'Manage ApplicationInformation Resource',
  44: 'Manage Authorization Resource',

  /**
   * @deprecated replaced by FB 51
   */
  46: 'Core Retail Customer',

  /**
   * @deprecated replaced by FB 67
   */
  47: 'REST for Retail Customer Bulk',

  /**
   * @deprecated replaced by FB 66
   */
  48: 'SFTP for Retail Customer Bulk',

  49: 'Retail Customer Management REST',
  50: 'Retail Customer Resource Level REST',
  51: 'Retail Customer Common',
  52: 'Retail Customer Download My Data',
  53: 'Retail Customer Connect My Data',
  54: 'Retail Customer Basic Information',
  55: 'Retail Customer Demographic Information',
  56: 'Retail Customer Billing Information',
  57: 'Retail Customer AccountAgreement Information',
  58: 'Retail Customer ServiceLocation Information',
  59: 'Retail Customer ServiceSupplier Information',
  60: 'Retail Customer Meter Information',
  61: 'Retail Customer EndDevice Information',
  62: 'Retail Customer ProgramDateIdMappings Information',
  64: 'Retail Customer Security and Privacy',
  65: 'Retail Customer Authorization and Authentication w/o Pre-Negotiated Scope',
  66: 'SFTP for Retail Customer Bulk',
  67: 'REST for Retail Customer Bulk',
  68: 'Retail Customer Query Parameters',
  69: 'Retail Customer PUSH Model',
  70: 'Retail Customer Offline Authorization'
})

function getFunctionBlockByName(
  functionBlockName: (typeof availableFunctionBlocks)[keyof typeof availableFunctionBlocks]
): keyof typeof availableFunctionBlocks | undefined {
  const functionBlock = Object.keys(availableFunctionBlocks).find(
    (possibleFunctionBlock) => {
      return (
        availableFunctionBlocks[possibleFunctionBlock] === functionBlockName
      )
    }
  )

  if (functionBlock === undefined) {
    return undefined
  }

  return Number.parseInt(
    functionBlock,
    10
  ) as keyof typeof availableFunctionBlocks
}

export class GreenButtonFunctionBlockBuilder {
  readonly #functionBlocks = new Set<keyof typeof availableFunctionBlocks>()

  constructor(functionBlockString = '') {
    const functionBlockSplit = functionBlockString.startsWith('FB=')
      ? functionBlockString.slice(3).split('_')
      : functionBlockString.split('_')

    for (const functionBlock of functionBlockSplit) {
      this.#functionBlocks.add(
        Number.parseInt(
          functionBlock,
          10
        ) as keyof typeof availableFunctionBlocks
      )
    }
  }

  addFunctionBlock(functionBlock: keyof typeof availableFunctionBlocks): void {
    this.#functionBlocks.add(functionBlock)
  }

  addFunctionBlockByName(
    functionBlockName: (typeof availableFunctionBlocks)[keyof typeof availableFunctionBlocks]
  ): boolean {
    const functionBlock = getFunctionBlockByName(functionBlockName)

    if (functionBlock !== undefined) {
      this.addFunctionBlock(functionBlock)
      return true
    }

    return false
  }

  removeFunctionBlock(
    functionBlock: keyof typeof availableFunctionBlocks
  ): void {
    this.#functionBlocks.delete(functionBlock)
  }

  hasFunctionBlock(
    functionBlock: keyof typeof availableFunctionBlocks
  ): boolean {
    return this.#functionBlocks.has(functionBlock)
  }

  toString(): string {
    return [...this.#functionBlocks.values()].join('_')
  }
}