indicator renaming

graphics/elements/indicators/LED.lua

@@ -0,0 +1,104 @@
+-- Indicator "LED" Graphics Element
+
+local util    = require("scada-common.util")
+
+local element = require("graphics.element")
+local flasher = require("graphics.flasher")
+
+---@class indicator_led_args
+---@field label string indicator label
+---@field colors cpair on/off colors (a/b respectively)
+---@field min_label_width? integer label length if omitted
+---@field flash? boolean whether to flash on true rather than stay on
+---@field period? PERIOD flash period
+---@field parent graphics_element
+---@field id? string element id
+---@field x? integer 1 if omitted
+---@field y? integer auto incremented if omitted
+---@field fg_bg? cpair foreground/background colors
+---@field hidden? boolean true to hide on initial draw
+
+-- new indicator LED
+---@nodiscard
+---@param args indicator_led_args
+---@return graphics_element element, element_id id
+local function indicator_led(args)
+    element.assert(type(args.label) == "string", "label is a required field")
+    element.assert(type(args.colors) == "table", "colors is a required field")
+
+    if args.flash then
+        element.assert(util.is_int(args.period), "period is a required field if flash is enabled")
+    end
+
+    args.height = 1
+    args.width = math.max(args.min_label_width or 0, string.len(args.label)) + 2
+
+    local flash_on = true
+
+    -- create new graphics element base object
+    local e = element.new(args)
+
+    e.value = false
+
+    -- called by flasher when enabled
+    local function flash_callback()
+        e.w_set_cur(1, 1)
+
+        if flash_on then
+            e.w_blit("\x8c", args.colors.blit_a, e.fg_bg.blit_bkg)
+        else
+            e.w_blit("\x8c", args.colors.blit_b, e.fg_bg.blit_bkg)
+        end
+
+        flash_on = not flash_on
+    end
+
+    -- enable light or start flashing
+    local function enable()
+        if args.flash then
+            flash_on = true
+            flasher.start(flash_callback, args.period)
+        else
+            e.w_set_cur(1, 1)
+            e.w_blit("\x8c", args.colors.blit_a, e.fg_bg.blit_bkg)
+        end
+    end
+
+    -- disable light or stop flashing
+    local function disable()
+        if args.flash then
+            flash_on = false
+            flasher.stop(flash_callback)
+        end
+
+        e.w_set_cur(1, 1)
+        e.w_blit("\x8c", args.colors.blit_b, e.fg_bg.blit_bkg)
+    end
+
+    -- on state change
+    ---@param new_state boolean indicator state
+    function e.on_update(new_state)
+        e.value = new_state
+        if new_state then enable() else disable() end
+    end
+
+    -- set indicator state
+    ---@param val boolean indicator state
+    function e.set_value(val) e.on_update(val) end
+
+    -- draw label and indicator light
+    function e.redraw()
+        e.on_update(e.value)
+        if string.len(args.label) > 0 then
+            e.w_set_cur(3, 1)
+            e.w_write(args.label)
+        end
+    end
+
+    -- initial draw
+    e.redraw()
+
+    return e.complete()
+end
+
+return indicator_led