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Flow solver

The flow solver uses the following pseudo-code to pass the ask from the operation to the buffer.

Note that the algorithm currently treats all alternates as if their type is “PRIORITY”.
An extension of the algorithm is required to support “MINCOST”, “MINPENALTY”, and “MINCOSTPENALTY” with the right logic. Feel free to submit a contribution, or contact us if you require such functionality.

If the flow has no alternates then
  // Without alternates
  If the requested date is outside of the effective date range of the flow
    Reply that the request can’t be met.
  else
    Ask the buffer solver for the quantity and date.
    If the buffer reply is of quantity 0 and the next ask date is later than the effectivity end date
      Limit the next ask date to the effectivity end date
    Return the promised quantity and next ask date.

else

  // Alternate flows
  Sort all alternate flows in order of priority
  Switch the planning mode to constrained
  For each alternate
    Switch the operation to the alternate
    Ask the buffer solver for the quantity and date
    If the buffer reply is above 0
      Return the planned quantity and next date
  If no alternate found any supply
    If the plan type is unconstrained then
      Replan in unconstrained mode on the primary alternate
      Return full quantity on requested date
    else
      Return 0 and next date

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