Clarify this Javascript ternary

Question

Can someone split this nested ternary into multiple ternaries or other code or explain it in English? I've never come across a nested ternary like this so I'm not sure the order of operations:

var EqualizeCheck = (IIO.ReadDigitalInput(IO_GROUP_CHARGERS, subGroupName, IO_ITEM_ENABLEEQUALIZE) == IO_INPUT_ON) ? (EqualizeCompleteTime != "") ? (EqualizeCompleteTime <= CurrentDateTime) ? true : false : false : true;

Answer 1

To work through it step by step, first separate the most nested condition (Look for a complete condition ? value : value statement) In this case that's this bit:

var EqualizeCheck = (IIO.ReadDigitalInput(IO_GROUP_CHARGERS, subGroupName, IO_ITEM_ENABLEEQUALIZE) == IO_INPUT_ON) ? (EqualizeCompleteTime != "") ? (EqualizeCompleteTime <= CurrentDateTime) ? true : false : false : true;

Separate that out and repeat for each ternary condition, until you have something like this:

// Condition 1:
(IIO.ReadDigitalInput(IO_GROUP_CHARGERS, subGroupName, IO_ITEM_ENABLEEQUALIZE) == IO_INPUT_ON) ? 
    // Condition 1 == true, check the next condition
    // Condition 2: 
    (EqualizeCompleteTime != "") ? 
        // Condition 2 == true, check the next condition
        // Condition 3:
        (EqualizeCompleteTime <= CurrentDateTime) ? 
            // Condition 3 == true, return true
            true :
            // Condition 3 == false, return false
            false :
        // Condition 2 == false, return false
        false :
    // Condition 1 == false, return true
    true;

Since this essentially boils down to two success conditions (Either where condition 1 is false, or where condition 2 and 3 are both true), you can vastly simplify it to this:

var EqualizeCheck = 
  !IIO.ReadDigitalInput(IO_GROUP_CHARGERS, subGroupName, IO_ITEM_ENABLEEQUALIZE) == IO_INPUT_ON) ||
  ( 
    EqualizeCompleteTime != "" &&
    EqualizeCompleteTime <= CurrentDateTime
  )