class Sus::Output::Progress

def self.now
	::Process.clock_gettime(Process::CLOCK_MONOTONIC)
end

def average_duration
	if @current > 0
		duration / @current
	end
end

def clear
	@lines&.clear
end

def duration
	Progress.now - @start_time
end

def estimated_remaining_time
	if average_duration = self.average_duration
		average_duration * remaining
	end
end

def expand(amount = 1)
	@total += amount
	
	@bar&.update(@current, @total, self.to_s)
	@lines&.redraw(0)
	
	return self
end

def formatted_duration(duration)
	seconds = duration.floor
	
	if seconds < 60.0
		return "#{seconds}s"
	end
	
	minutes = (duration / 60.0).floor
	seconds = (seconds - (minutes * 60)).round
	
	if minutes < 60.0
		return "#{minutes}m#{seconds}s"
	end
	
	hours = (minutes / 60.0).floor
	minutes = (minutes - (hours * 60)).round
	
	if hours < 24.0
		return "#{hours}h#{minutes}m"
	end
	
	days = (hours / 24.0).floor
	hours = (hours - (days * 24)).round
	
	return "#{days}d#{hours}h"
end

def increment(amount = 1)
	@current += amount
	
	@bar&.update(@current, @total, self.to_s)
	@lines&.redraw(0)
	
	return self
end

def initialize(output, total = 0, minimum_output_duration: 1.0)
	@output = output
	@subject = subject
	
	@start_time = Progress.now
	
	if @output.interactive?
		@bar = Bar.new
		@lines = Lines.new(@output)
		@lines[0] = @bar
	end
	
	@current = 0
	@total = total
end

def progress
	@current.to_f / @total.to_f
end

def remaining
	@total - @current
end

def report(index, context, state)
	@lines&.[]=(index+1, Status.new(state, context))
	
	return self
end

def to_s
	if estimated_remaining_time = self.estimated_remaining_time
		"#{@current}/#{@total} completed in #{formatted_duration(self.duration)}, #{formatted_duration(estimated_remaining_time)} remaining"
	else
		"#{@current}/#{@total} completed"
	end
end