# frozen_string_literal: true

# Released under the MIT License.
# Copyright, 2018-2023, by Samuel Williams.

require_relative 'coverage'
require_relative 'wrapper'

require 'set'

module Covered
	class Files < Base
		class State
			def self.for(path, **options)
				self.new(Source.new(path, **options))
			end
			
			def initialize(source)
				@source = source
				@counts = []
				@annotations = {}
			end
			
			def [](lineno)
				@counts[lineno]
			end
			
			attr :counts
			attr :annotations
			
			def annotate(lineno, annotation)
				@annotations[lineno] ||= []
				@annotations[lineno] << annotation
			end
			
			def mark(lineno, value = 1)
				# As currently implemented, @counts is base-zero rather than base-one.
				# Line numbers generally start at line 1, so the first line, line 1, is at index 1. This means that index[0] is usually nil.
				Array(value).each_with_index do |value, index|
					offset = lineno + index
					if @counts[offset]
						@counts[offset] += value
					else
						@counts[offset] = value
					end
				end
			end
			
			def merge!(coverage)
				coverage.counts.each_with_index do |count, index|
					if count
						@counts[index] ||= 0
						@counts[index] += count
					end
				end
				
				@annotations.merge!(coverage.annotations) do |lineno, a, b|
					Array(a) + Array(b)
				end
			end
			
			def coverage
				Coverage.new(@source, @counts, @annotations)
			end
		end
		
		def initialize(*)
			super
			
			@paths = {}
		end
		
		attr_accessor :paths
		
		def [](path)
			@paths[path] ||= State.for(path)
		end
		
		def empty?
			@paths.empty?
		end
		
		def mark(path, lineno, value)
			self[path].mark(lineno, value)
		end
		
		def annotate(path, lineno, value)
			self[path].annotate(lineno, value)
		end
		
		def add(coverage)
			self[coverage.path].merge!(coverage)
		end
		
		def each
			return to_enum unless block_given?
			
			@paths.each_value do |state|
				yield state.coverage
			end
		end
		
		def clear
			@paths.clear
		end
	end
	
	class Include < Wrapper
		def initialize(output, pattern, base = "")
			super(output)
			
			@pattern = pattern
			@base = base
		end
		
		attr :pattern
		
		def glob
			paths = Set.new
			root = self.expand_path(@base)
			pattern = File.expand_path(@pattern, root)
			
			Dir.glob(pattern) do |path|
				unless File.directory?(path)
					paths << File.realpath(path)
				end
			end
			
			return paths
		end
		
		def each(&block)
			paths = glob
			
			super do |coverage|
				paths.delete(coverage.path)
				
				yield coverage
			end
			
			paths.each do |path|
				yield Coverage.for(path)
			end
		end
	end
	
	class Skip < Filter
		def initialize(output, pattern)
			super(output)
			
			@pattern = pattern
		end
		
		attr :pattern
		
		if Regexp.instance_methods.include? :match?
			# This is better as it doesn't allocate a MatchData instance which is essentially useless.
			def match? path
				!@pattern.match?(path)
			end
		else
			def match? path
				!(@pattern =~ path)
			end
		end
	end
	
	class Only < Filter
		def initialize(output, pattern)
			super(output)
			
			@pattern = pattern
		end
		
		attr :pattern
		
		def match?(path)
			@pattern === path
		end
	end
	
	class Root < Filter
		def initialize(output, path)
			super(output)
			
			@path = path
		end
		
		attr :path
		
		def expand_path(path)
			File.expand_path(super, @path)
		end
		
		def relative_path(path)
			if path.start_with?(@path)
				path.slice(@path.size+1, path.size)
			else
				super
			end
		end
		
		def match?(path)
			path.start_with?(@path)
		end
	end
end