require "colorize"
require "specparser"

require "./exception.cr"
require "./config.cr"
require "./backends.cr"

class Package::Context
	property working_directory = "/tmp/packaging"
	property sources_directory = Dir.current
	property packages_directory = Dir.current

	#alias Backends = Backend::Packaging | Backend::Building | Backend::Splitter
	property user_instructions  = Hash(String, Instructions).new

	property configure_backends = Hash(String, Backend::Building).new
	property building_backends  = Hash(String, Backend::Building).new
	property install_backends   = Hash(String, Backend::Building).new

	getter packaging_backends   = Hash(String, Backend::Packaging).new
	getter splitter_backends    = Hash(String, Backend::Splitter).new

	# General options, to add to the recipe before reading it.
	getter options              = Hash(String, String).new

	getter all_phase_names = [
			"sources-split",
			"pre-configure", "configure",
			"pre-build", "build",
			"pre-install", "install", "post-install",
		]

	# Directories where ports can be found.
	getter repositories = [] of String

	# Well, this will need configuration, auto-detection and conversion,
	# but it’ll be kind of enough for now.
	property architecture = "x86_64"

	# prefixes for `packaging` running environment and child processes
	# = where to search for binaries and libraries for the build
	property prefixes = ["/usr/baguette", "/usr", "/"]

	# By default, building a package only uses one core
	property build_cores = 1

	property recipe : Recipe? = nil


	def initialize
		# Add package backends: baguette (package-tools) and apk.
		# They implement the Backend::Packaging abstract class:
		#   init (@name) + package (context, package) method
		@packaging_backends["baguette"] = Backend::Packaging::Baguette.new
		@packaging_backends["apk"]      = Backend::Packaging::APK.new
		@packaging_backends["pkgutils"] = Backend::Packaging::Pkgutils.new

		@selected_packaging_backend = @packaging_backends["baguette"]

		# Add building backends: configuration, build and install.
		@configure_backends["autotools"] = Backend::Configure.autotools
		@configure_backends["cmake"]     = Backend::Configure.cmake
		@building_backends["make"]       = Backend::Build.make
		@install_backends["make"]        = Backend::Install.make

		# Split = new package from a recipe, each one with different files being included.
		@splitter_backends["man"] = Backend::Splitter.man @prefixes
		@splitter_backends["dev"] = Backend::Splitter.dev @prefixes
		@splitter_backends["doc"] = Backend::Splitter.doc @prefixes
		# src isn't really a split, files already are copied before build.
		#@splitter_backends << Backend::Splitter.src @prefixes
	end

	def packaging_backend=(name : String)
		@selected_packaging_backend = @packaging_backends[name].not_nil!
	end

	def packaging_backend=(backend : Backend::Packaging)
		@selected_packaging_backend = backend
	end

	def package(package : Package) : Bool
		@selected_packaging_backend.package @packages_directory, @architecture, package
	end

	def read_recipe(filename : String)
		@recipe = Recipe.new self, filename
		@recipe.not_nil!
	end

	def find_recipe(name : String) : Recipe?
		recipe_file_name = ""

		repo = @repositories.find do |repo|
			repo_dir_name = "#{repo}/#{name}"
			recipe_file_name = "#{repo_dir_name}/recipe.spec"

			if Dir.exists?(repo_dir_name) && File.exists?(recipe_file_name)
				next true
			end
		end

		read_recipe recipe_file_name if repo
	end

	def read_configuration(filename : String)
		specs = SpecParser.parse(File.read(filename))

		specs.assignments.each do |key, value|
			case key
			when "packages-directory"
				@packages_directory = value.as_s
			when "sources-directory"
				@sources_directory = value.as_s
			when "working-directory"
				@working_directory = value.as_s

			when "prefixes"
				# Prefixes during the build process.
				@prefixes = value.as_a_or_s

			when "build-cores"
				# NB of cores used to compile applications.
				@build_cores = value.as_s.to_i

			when "environment"
				# Environment variables during the build process.
				value.as_a_or_s.each do |entry|
					match = entry.split(':').map(
						&.gsub(/^[ \t]*/, "").gsub(/[ \t]*$/, ""))

					if match.size != 2
						STDERR.puts "WARNING: misformed environment definition: #{entry}"
						next
					end

					key, value = match
					Do.environment[key] = value
					if Baguette::Context.verbosity > 2
						STDOUT.puts "environment: #{key} => #{value}"
					end
				end

			when "options"
				value.as_a_or_s.each do |option|
					match  = option.split(':').map(&.strip)

					if match.size != 2
						STDERR.puts "WARNING: misformed option: #{option}"
						next
					end

					key, value = match

					@options[key] = value
				end

			# (default) user instructions (for testing).
			when /(?<phase>(pre-)?(configure|build|install)|post-install)/
				phase = $~["phase"]
				@user_instructions[phase] = Instructions.new(phase).<<(value.as_s_or_ls)

			when "package-manager"
				# Targeted package manager (default: package, for BaguetteOS).
				begin
					self.packaging_backend = value.as_s
				rescue e
					STDERR.puts "Error during selecting packaging backend: #{e}"
					STDERR.puts "#{value.as_s} seems not to be a valid backend"
					STDERR.puts "valid backends:"
					@packaging_backends.each do |name, backend|
						STDERR.puts "- #{name}"
					end
					exit 1
				end
			end
		end
	end

	def install(packages : Array(String))
		@selected_packaging_backend.install packages
	end
end