Log digest

# title: Log digest
# category: Vibescript Showcase
# difficulty: Showcase
# summary: Parse log lines, group them by level, and count each group.
# description: each_line splits the log. partition, group_by, and select turn the lines into a short report.
# tags: operations, strings, collections, logs
# vibe: 0.4

def digest(text: string) -> array
  entries = []
  text.each_line do |line|
    trimmed = line.strip
    if !trimmed.empty?
      parts = trimmed.partition(" ")
      entries.push({ level: parts[0], message: parts[2] })
    end
  end
  entries
end

def counts_by_level(entries: array) -> hash
  counts = {}
  grouped = entries.group_by { |entry| entry[:level] }
  grouped.each do |level, items|
    counts[level] = items.length
  end
  counts
end

def run
  log = "INFO service started\nWARN disk at 82%\nERROR upstream timeout\nINFO healthy\nWARN memory high"
  entries = digest(log)

  {
    entry_count: entries.length,
    first_message: entries[0][:message],
    counts_by_level: counts_by_level(entries),
    warnings: entries.select { |entry| entry[:level] == "WARN" }.map { |entry| entry[:message] }
  }
end