module BomRainReport

# File lib/bom_rain_report.rb, line 133
def apply_rain_chance_bar(plain, percent, style:)
  percent = [[percent.to_f, 0].max, 100].min
  bar_zone = rain_chance_bar_zone(plain)
  return plain if bar_zone.empty?

  zone_width = bar_zone.length
  filled = rain_chance_bar_fill_length(bar_zone, percent)
  return plain if filled <= 0

  head = plain[0, filled]
  zone_tail = plain[filled, zone_width - filled] || ""
  after_zone = plain[zone_width..] || ""

  return IrcFormat.decorate(bar_zone, style) if after_zone.empty? && zone_tail.empty?

  empty_lead = "#{IrcFormat::RESET}#{BAR_EMPTY_STYLE}"
  empty_lead += BAR_DIGIT_GUARD if zone_tail.match?(/\A\d/)
  result = "#{style}#{head}#{empty_lead}#{zone_tail}"
  result += "#{IrcFormat::RESET}#{after_zone}" unless after_zone.empty?
  result
end

# File lib/bom_rain_report.rb, line 68
def compact_rainfall(amount)
  amount.to_s.strip.gsub(/\s+to\s+/, "-")
end

# File lib/bom_rain_report.rb, line 48
def compact_temp_celsius(value)
  text = value.to_s.strip
  return nil if text.empty?

  text.sub(/\s*°C\z/i, "")
end

# File lib/bom_rain_report.rb, line 40
def format_period_short(period)
  DAY_SHORT_NAMES.each do |pattern, short|
    return short if period.to_s.match?(pattern)
  end

  period.to_s.split.first.to_s[0, 3].capitalize
end

# File lib/bom_rain_report.rb, line 155
def format_rain_entry(day)
  plain = format_rain_entry_plain(day)
  return nil unless plain

  percent = parse_rain_chance_percent(day[:rain_chance])
  mm = parse_rainfall_mm(day[:rainfall])
  style = rain_style_for_mm(mm)
  bar = apply_rain_chance_bar(plain, percent, style: style)
  bar == plain ? bar : "#{bar}#{IrcFormat::RESET}"
end

# File lib/bom_rain_report.rb, line 103
def format_rain_entry_plain(day)
  chance = day[:rain_chance]
  amount = day[:rainfall]
  return nil if chance.nil? && amount.nil?

  parts = [format_period_short(day[:period])]
  parts << chance if chance
  parts << compact_rainfall(amount) if amount
  temps = format_rain_temps(day)
  parts << temps if temps
  parts.join(" ")
end

# File lib/bom_rain_report.rb, line 170
def format_rain_forecast(days)
  entries = days.filter_map { |day| format_rain_entry(day) }
  return nil if entries.empty?

  entries.join(rain_day_divider)
end

# File lib/bom_rain_report.rb, line 55
def format_rain_temps(day)
  min = compact_temp_celsius(day[:min])
  max = compact_temp_celsius(day[:max])

  if min && max
    "#{min}-#{max}°C"
  elsif max
    "#{max}°C"
  elsif min
    "#{min}°C"
  end
end

# File lib/bom_rain_report.rb, line 72
def parse_rain_chance_percent(chance)
  text = chance.to_s.strip
  return 0.0 if text.empty?

  match = text.match(/\A(\d+(?:\.\d+)?)\s*%/)
  match ? match[1].to_f : 0.0
end

# File lib/bom_rain_report.rb, line 80
def parse_rainfall_mm(amount)
  text = amount.to_s.strip.downcase
  return 0.0 if text.empty?

  numbers = text.scan(/(\d+(?:\.\d+)?)/).flatten.map(&:to_f)
  return 0.0 if numbers.empty?

  numbers.max
end

# File lib/bom_rain_report.rb, line 124
def rain_chance_bar_fill_length(bar_zone, percent)
  percent = [[percent.to_f, 0].max, 100].min
  zone_width = bar_zone.to_s.length
  return 0 if percent <= 0 || zone_width.zero?
  return zone_width if percent >= 100

  [(percent * zone_width / 100.0).round, zone_width].min
end

# File lib/bom_rain_report.rb, line 116
def rain_chance_bar_zone(plain)
  text = plain.to_s
  return "" if text.empty?
  return "" unless text.match?(/\A\S+\s+\d+(?:\.\d+)?%/)

  text
end

# File lib/bom_rain_report.rb, line 166
def rain_day_divider
  " #{IrcFormat.muted('|')} "
end

# File lib/bom_rain_report.rb, line 95
def rain_style_components(mm)
  mm = [mm.to_f, 0].max
  _stop, fg, bg = RAIN_STYLE_STOPS.reduce(RAIN_STYLE_STOPS.first) do |chosen, candidate|
    mm >= candidate[0] ? candidate : chosen
  end
  [fg, bg]
end

# File lib/bom_rain_report.rb, line 90
def rain_style_for_mm(mm)
  fg, bg = rain_style_components(mm)
  IrcFormat.color(fg, bg)
end