28 lines
628 B
Ruby
28 lines
628 B
Ruby
module TimelineLookup
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# Given an array of tuples containing (id, days_ago), return at most `max_values` worth of a
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# lookup table to help the front end timeline display dates associated with posts
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def self.build(tuples, max_values = 300)
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result = []
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every = (tuples.size.to_f / max_values).ceil
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last_days_ago = -1
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tuples.each_with_index do |t, idx|
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return result unless t.is_a?(Array)
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next unless (idx % every) === 0
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days_ago = t[1]
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if (days_ago != last_days_ago)
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result << [idx + 1, days_ago]
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last_days_ago = days_ago
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end
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end
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result
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end
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end
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