require "uri"
require "json"
require "net/http"

url = URI("https://api.swep.net/calculateSinglePhase")

https = Net::HTTP.new(url.host, url.port)
https.use_ssl = true

request = Net::HTTP::Post.new(url)
request["X-API-KEY"] = "YOUR_API_KEY"
request["Content-Type"] = "application/json"
request.body = JSON.dump({
  "inputs": {
    "calculationMethod": "Design",
    "selectedFluidSide1": {
      "fluidId": 53,
      "isGas": false,
      "inputValue": "__RUBY\#%0NULL__"
    },
    "selectedFluidSide2": {
      "fluidId": 53,
      "isGas": false,
      "inputValue": "__RUBY\#%0NULL__"
    },
    "coCurrent": false,
    "selectedHeatExchangers": [
      {
        "heatExchangerInputType": "Parent",
        "id": 1
      }
    ],
    "heatLoad": {
      "amount": 1500,
      "unit": "HeatLoadUnit.Kilowatt"
    },
    "inletTemperatureSide1": {
      "amount": 80,
      "unit": "TemperatureUnit.DegreeCelsius"
    },
    "inletTemperatureSide2": {
      "amount": 20,
      "unit": "TemperatureUnit.DegreeCelsius"
    },
    "outletTemperatureSide1": {
      "amount": 40,
      "unit": "TemperatureUnit.DegreeCelsius"
    },
    "outletTemperatureSide2": {
      "amount": 50,
      "unit": "TemperatureUnit.DegreeCelsius"
    },
    "flowSide1": "__RUBY\#%0NULL__",
    "flowSide2": "__RUBY\#%0NULL__",
    "maxPressureDropSide1": {
      "amount": 20000,
      "unit": "PressureUnit.Pascal"
    },
    "maxPressureDropSide2": {
      "amount": 20000,
      "unit": "PressureUnit.Pascal"
    },
    "numberOfPasses": "__RUBY\#%0NULL__",
    "numberOfPlates": "__RUBY\#%0NULL__",
    "numberOfPlatesStack1": "__RUBY\#%0NULL__",
    "numberOfPlatesStack2": "__RUBY\#%0NULL__",
    "oversurface": "__RUBY\#%0NULL__",
    "portSwitch": true,
    "autoperformance": false
  }
})

response = https.request(request)
puts response.read_body