local shared = require 'shared'
local compactify = shared.compactify
local update_power_usage = shared.update_power_usage

local function format_energy(energy)
	return string.format('%.2f', energy * 60 / 1000000) .. 'MW'
end

local function update_gui(gui, fresh_gui)
	local unit_data = global.units[gui.tags.unit_number]
	if not unit_data then gui.destroy() return end
	local content_flow = gui.content_frame.content_flow
	local entity = unit_data.entity
	local powersource = unit_data.powersource
	
	if not entity.valid or not powersource.valid then return end
	
	local count = unit_data.count
	local inventory = unit_data.inventory
	local deconstructed = entity.to_be_deconstructed()
	local inventory_count = 0
	if unit_data.item then
		inventory_count = inventory.get_item_count(unit_data.item)
		if fresh_gui or not deconstructed then
			content_flow.storage_flow.content_sprite.sprite = 'item/' .. unit_data.item
			content_flow.storage_flow.current_storage.caption = {
				'',
				{'', '[font=default-semibold][color=255,230,192]', game.item_prototypes[unit_data.item].localised_name},
				{'', ':[/color][/font] ', compactify(count + inventory_count)}
			}
		end
	end
	local visible = not not unit_data.item
	content_flow.storage_flow.visible = visible
	content_flow.storage_seperator.visible = visible
	content_flow.io_flow.visible = visible
	content_flow.no_input_item.visible = not visible
	
	content_flow.electric_flow.electricity.value = powersource.energy / powersource.electric_buffer_size
	content_flow.electric_flow.consumption.caption = format_energy(powersource.energy) .. '/' .. format_energy(powersource.electric_buffer_size)
	if unit_data.item then update_power_usage(unit_data, count + inventory_count) end
	
	local status, img
	if entity.to_be_deconstructed() then
		status = {'entity-status.marked-for-deconstruction'}
		img = 'utility/status_not_working'
		content_flow.electric_flow.consumption.caption = ''
	elseif powersource.energy == 0 then
		status = {'entity-status.no-power'}
		img = 'utility/status_not_working'
	elseif not unit_data.item then
		for name, _ in pairs(inventory.get_contents()) do
			if not shared.check_for_basic_item(name) then
				status = {'entity-status.cannot-store', game.item_prototypes[name].localised_name}
				img = 'utility/status_not_working'
				content_flow.electric_flow.consumption.caption = ''
				goto cannot_store
			end
		end
		status = {'entity-status.no-input-item'}
		img = 'utility/status_not_working'
		::cannot_store::
	elseif powersource.energy < powersource.electric_buffer_size * 0.9 then
		status = {'entity-status.low-power'}
		img = 'utility/status_yellow'
	else
		status = {'entity-status.working'}
		img = 'utility/status_working'
	end
	
	content_flow.status_flow.status_text.caption = status
	content_flow.status_flow.status_sprite.sprite = img
end

script.on_nth_tick(2, function(event)
	for _, player in pairs(game.connected_players) do
		if player.opened_gui_type == defines.gui_type.item then
			local gui = player.gui.relative.memory_unit_gui
			if gui then update_gui(gui) end
		end
	end
end)

script.on_event(defines.events.on_player_changed_surface, function(event)
	local player = game.get_player(event.player_index)
	if player.opened_gui_type == defines.gui_type.item then
		local gui = player.gui.relative.memory_unit_gui
		if gui then gui.destroy() end
	end
end)

script.on_event(defines.events.on_gui_opened, function(event)                
	if event.gui_type ~= defines.gui_type.entity or not event.entity or event.entity.name ~= 'memory-unit' then return end
	
	local player = game.get_player(event.player_index)
	local entity = event.entity
	shared.open_inventory(player)
               
	local main_frame = player.gui.relative.add{
		type = 'frame', name = 'memory_unit_gui', caption = {'entity-name.memory-unit'}, direction = 'vertical',
		anchor = {
			gui = defines.relative_gui_type.item_with_inventory_gui,
			position = defines.relative_gui_position.right
		}
	}
	main_frame.style.width = 448
	main_frame.tags = {unit_number = entity.unit_number}
               
	local content_frame = main_frame.add{type = 'frame', name = 'content_frame', direction = 'vertical', style = 'inside_shallow_frame_with_padding'}
	local content_flow = content_frame.add{type = 'flow', name = 'content_flow', direction = 'vertical'}
	content_flow.style.vertical_spacing = 8
	content_flow.style.margin = {-4, 0, -4, 0}
	content_flow.style.vertical_align = 'center'
	
	local electric_flow = content_flow.add{type = 'flow', name = 'electric_flow', direction = 'horizontal'}
	electric_flow.style.vertical_align = 'center'
	electric_flow.style.horizontal_align = 'right'
	electric_flow.style.width = 400
	electric_flow.style.bottom_margin = -32
	electric_flow.add{type = 'label', name = 'consumption'}.style.right_margin = 4
	electric_flow.add{type = 'progressbar', name = 'electricity', style = 'electric_satisfaction_progressbar'}.style.width = 150
               
	local status_flow = content_flow.add{type = 'flow', name = 'status_flow', direction = 'horizontal'}
	status_flow.style.vertical_align = 'center'
	status_flow.style.top_margin = 4
	local status_sprite = status_flow.add{type = 'sprite', name = 'status_sprite'}
	status_sprite.resize_to_sprite = false
	status_sprite.style.size = {16, 16}
	local status_text = status_flow.add{type = 'label', name = 'status_text'}
	
	local entity_preview = content_flow.add{type = 'entity-preview', name = 'entity_preview', style = 'mu_entity_preview'}
	entity_preview.entity = entity
	entity_preview.visible = true
	entity_preview.style.height = 155
	
	local storage_flow = content_flow.add{type = 'flow', name = 'storage_flow', direction = 'horizontal'}
	storage_flow.style.vertical_align = 'center'
	
	local content_sprite = storage_flow.add{type = 'sprite', name = 'content_sprite'}
	content_sprite.resize_to_sprite = false
	content_sprite.style.size = {32, 32}
	storage_flow.add{type = 'label', name = 'current_storage'}
	content_flow.add{type = 'line', name = 'storage_seperator'}
	
	local io_flow = content_flow.add{type = 'flow', name = 'io_flow', direction = 'horizontal'}
	storage_flow.style.vertical_align = 'center'         
	local bulk_insert = io_flow.add{type = 'sprite-button', name = 'bulk_insert', style = 'inventory_slot', sprite = 'bulk-insert', tooltip = {'mod-gui.bulk-insert'}}
	bulk_insert.tags = {unit_number = entity.unit_number}
	local bulk_extract = io_flow.add{type = 'sprite-button', name = 'bulk_extract', style = 'inventory_slot', sprite = 'bulk-extract', tooltip = {'mod-gui.bulk-extract'}}
	bulk_extract.tags = {unit_number = entity.unit_number}
	
	local no_input_item = content_flow.add{type = 'sprite-button', name = 'no_input_item', style = 'inventory_slot', tooltip = {'mod-gui.no-input-item'}}
	no_input_item.tags = {unit_number = entity.unit_number}
               
	update_gui(main_frame, true)
end)

script.on_event(defines.events.on_gui_closed, function(event)
	local player = game.get_player(event.player_index)
	if event.gui_type == defines.gui_type.item then
		local gui = player.gui.relative.memory_unit_gui
		if gui then gui.destroy() end
	end
end)

local function bulk_io(event, element)
	local player = game.get_player(event.player_index)
	local inventory = player.get_main_inventory()
	local unit_data = global.units[element.tags.unit_number]
	local item = unit_data.item
	if not item then return end
	
	local count = (event.button == defines.mouse_button_type.right) and unit_data.stack_size * #inventory or unit_data.stack_size
	if element.name == 'bulk_insert' then -- insert
		local amount_removed = inventory.remove{name = item, count = count}
		unit_data.count = unit_data.count + amount_removed
	elseif element.name == 'bulk_extract' then -- extract
		local unit_inventory = unit_data.inventory
		local inventory_count = unit_inventory.get_item_count(item)
			
		if inventory_count + unit_data.count < count then -- not enough items are in storage
			count = inventory_count + unit_data.count
		end
		
		if count == 0 then return end
		
		local amount_inserted = inventory.insert{name = item, count = count}
		unit_data.count = unit_data.count - amount_inserted
		if unit_data.count < 0 then
			unit_inventory.remove{name = item, count = -unit_data.count}
			unit_data.count = 0
		end
	end
	
	update_unit(unit_data, element.tags.unit_number, true)
end

local function prime_unit(event, element)
	local player = game.get_player(event.player_index)
	local stack = player.cursor_stack
	if not stack.valid_for_read or not shared.check_for_basic_item(stack.name) then return end
	local unit_data = global.units[element.tags.unit_number]
	
	unit_data.count = stack.count
	unit_data.item = stack.name
	unit_data.stack_size = stack.prototype.stack_size
	unit_data.comfortable = unit_data.stack_size * #unit_data.inventory / 2
	set_filter(unit_data)
	stack.clear()
	
	update_unit(unit_data, element.tags.unit_number, true)
	update_gui(player.gui.relative.memory_unit_gui)
end

script.on_event(defines.events.on_gui_click, function(event)
	local element = event.element
	if not element.tags or not element.tags.unit_number then return end
	if element.name == 'bulk_insert' or element.name == 'bulk_extract' then
		bulk_io(event, element)
	elseif element.name == 'no_input_item' then
		prime_unit(event, element)
	end
end)