Replace underscores and capitalize

postgre to mssql

let text = `
  CREATE TABLE [dbo].[images]
(
	[image_id] INT NOT NULL PRIMARY KEY, 
    [url] VARCHAR(200) NOT NULL, 
    [tour_id] INT NULL, 
    [user_id] INT NULL, 
    [created_on] DATETIME2(1) NULL DEFAULT GETDATE(), 
    CONSTRAINT [CK_images_tour_id] CHECK (tour_id is not null or user_id is not null), 
    CONSTRAINT [FK_images_users] FOREIGN KEY ([user_id]) REFERENCES [users]([user_id])
)
`;

var regex = /\[[a-z_A-Z]*\]/gi;

const capitalize = (word) => {
  return (word === null || word === '') ? '' : word[0].toUpperCase() + word.slice(1);
};

var newText = text.replace(regex, (x) => {
  var arr = x.split('_');

  var result = arr.map(z => capitalize(z.replace('[', '')));
  
  var joinBy = (result.includes('FK') || result.includes('CK')) ? '_' : '';
  
  return '[' + result.join(joinBy);
})

console.log(newText);