deferred class
	EL_JPEG_FILE_INFO_COMMAND_I

inherit
	EL_CAPTURED_OS_COMMAND_I
		rename
			make_default as make,
			eiffel_naming as camel_case_naming
		export
			{NONE} all
		redefine
			camel_case_naming, do_with_lines, new_representations, reset,
			set_has_error, make
		end

	EL_SETTABLE_FROM_ZSTRING
		rename
			make_default as make
		end

	EL_MODULE_FILE; EL_MODULE_TUPLE

feature {NONE} -- Initialization

	make
		do
			Precursor
--			Some devices like the Nokio 300 phone may have bad Exif.Photo.MakerNote field causing an infinite loop
--			in UTF-8 parsing. Treating output as encoding `Mixed_utf_8_latin_1' prevents this by forcing a UTF-8
--			validity check on each line. If UTF-8 is invalid it defaults to Latin-1 encoding.

			output_encoding := Mixed_utf_8_latin_1
		end

feature -- Access

	file_path: FILE_PATH

feature -- Exiv2 fields

	device_make: STRING

	model: STRING

	orientation: STRING

	resolution_unit: STRING

	software: STRING

feature -- Exiv2 measurements

	date_time: INTEGER

	date_time_original: INTEGER

	image_height: INTEGER
		do
			Result := image_length
		end

	image_length: INTEGER

	image_width: INTEGER

	pixel_x_dimension: INTEGER

	pixel_y_dimension: INTEGER

	x_resolution: INTEGER

	y_resolution: INTEGER

feature -- Status query

	has_date_time: BOOLEAN
		do
			Result := date_time.to_boolean
		end

	has_meta_data: BOOLEAN

feature -- Factory

	new_date_time: EL_DATE_TIME
		do
			create Result.make_from_epoch (date_time)
		end

feature -- Element change

	set_file_path (a_file_path: like file_path)
			--
		do
			file_path := a_file_path
--			put_path (var.file_path, a_file_path)
			execute
		end

feature {NONE} -- Implementation

	camel_case_naming: EL_NAME_TRANSLATER
		do
			Result := camel_case_translater ({EL_CASE}.lower)
		end

	do_with_lines (line_list: like new_output_lines)
			--
		local
			line, value, field_name, qualifier: ZSTRING
			found: BOOLEAN; value_column, count: INTEGER
		do
			across line_list as list loop
				line := list.item
				if line.starts_with (Name.exif) then
					line.remove_head (Name.exif.count + 1)
					value_column := 56; found := False
					across Name_part_list as part until found loop
						qualifier := part.item
						if line.starts_with (qualifier) then
							if qualifier = Name.thumbnail then
								line.remove (qualifier.count + 1) -- Remove dot
								value_column := value_column - 1
							else
								line.remove_head (qualifier.count + 1)
								value_column := value_column - qualifier.count - 1
							end
							field_name := line.substring_to (' ')
							if field_name ~ Name.make then
								field_name.prepend_compatible ("Device")
							end
							if field_table.has_imported_key (field_name) then
								value := line.substring_end (value_column)
								value.right_adjust
								field_table.found_item.set_from_string (Current, value)
							end
							found := True
						end
					end
					count := count + 1
				end
			end
			has_meta_data := count.to_boolean
			if date_time = 0 then
				date_time := date_time_original
			end
			if image_width = 0 then
				image_width := pixel_x_dimension
			end
			if image_length = 0 then
				image_length := pixel_y_dimension
			end
		end

	reset
		do
			Precursor
			has_meta_data := False

			date_time := 0; date_time_original := 0
			image_width := 0; image_length := 0
			x_resolution := 0; y_resolution := 0
			pixel_x_dimension := 0; pixel_y_dimension := 0

			create device_make.make_empty
			create model.make_empty
			create orientation.make_empty
			create resolution_unit.make_empty
			create software.make_empty
		end

	set_has_error (return_code: INTEGER)
		-- exiv2 has a non-standard way of indicating an error
		do
			has_error := File.byte_count (temporary_error_file_path) > 0
		end

feature {NONE} -- Reflection hints

	new_representations: like Default_representations
		do
			create Result.make (<<
				["date_time",				Date_representation],
				["date_time_original",	Date_representation]
			>>)
		end

feature {NONE} -- Constants

	Date_representation: EL_DATE_TIME_REPRESENTATION
		once
			create Result.make ("yyyy:[0]mm:[0]dd [0]hh:[0]mi:[0]ss")
		end

	Name: TUPLE [exif, image, make, photo, thumbnail: ZSTRING]
		once
			create Result
			Tuple.fill (Result, "Exif, Image, Make, Photo, Thumbnail")
		end

	Name_part_list: EL_ZSTRING_LIST
		once
			create Result.make_from_tuple (Name)
		end

	Template: STRING = "exiv2 -p a $file_path"

end