Module: InstagramConnect::TextSplitter

Defined in:
lib/instagram_connect/text_splitter.rb

Overview

Splits a reply that exceeds Meta's 1000-byte message ceiling into parts that fit.

Splitting rather than truncating is deliberate: a customer reading half an answer is worse than reading two bubbles, and the operator who wrote it has no way to know it was cut.

Class Method Summary collapse

Class Method Details

.split(text, limit: Media::Limits::TEXT_MAX_BYTES) ⇒ Object

Returns the parts to send, in order. A message already within the limit comes back as a single-element array, so callers have one code path.



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# File 'lib/instagram_connect/text_splitter.rb', line 13

def split(text, limit: Media::Limits::TEXT_MAX_BYTES)
  text = text.to_s
  return [ text ] if text.bytesize <= limit

  parts = []
  remaining = text

  while remaining.bytesize > limit
    chunk = take(remaining, limit)
    parts << chunk.rstrip
    remaining = remaining[chunk.length..].to_s.lstrip
  end

  # Text that divides exactly on a break leaves nothing over; appending an
  # empty part would send an empty bubble.
  parts << remaining unless remaining.empty?
  parts
end

.take(text, limit) ⇒ Object

The longest prefix that fits, broken at whitespace where possible so words survive. Falls back to a hard character break for input with no whitespace at all — a long URL, or a script that does not use spaces.



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# File 'lib/instagram_connect/text_splitter.rb', line 35

def take(text, limit)
  candidate = +""
  last_break = nil

  text.each_char do |char|
    break if candidate.bytesize + char.bytesize > limit

    candidate << char
    last_break = candidate.length if char.match?(/\s/)
  end

  return candidate if last_break.nil?

  candidate[0, last_break]
end