graphics library refactoring and bugfixes

graphics/elements/indicators/icon.lua

@@ -0,0 +1,66 @@
+-- Icon Indicator Graphics Element
+
+local util    = require("scada-common.util")
+
+local element = require("graphics.element")
+
+---@class icon_sym_color
+---@field color cpair
+---@field symbol string
+
+---@class icon_indicator_args
+---@field label string indicator label
+---@field states table state color and symbol table
+---@field value? integer default state, defaults to 1
+---@field min_label_width? integer label length if omitted
+---@field parent graphics_element
+---@field x? integer 1 if omitted
+---@field y? integer 1 if omitted
+---@field fg_bg? cpair foreground/background colors
+
+-- new icon indicator
+---@param args icon_indicator_args
+local function icon(args)
+    assert(type(args.label) == "string", "graphics.elements.indicators.icon: label is a required field")
+    assert(type(args.states) == "table", "graphics.elements.indicators.icon: states is a required field")
+
+    -- single line
+    args.height = 1
+
+    -- determine width
+    args.width = math.max(args.min_label_width or 1, string.len(args.label)) + 4
+
+    -- create new graphics element base object
+    local e = element.new(args)
+
+    -- state blit strings
+    local state_blit_cmds = {}
+    for i = 1, #args.states do
+        local sym_color = args.states[i]    ---@type icon_sym_color
+
+        table.insert(state_blit_cmds, {
+            text = " " .. sym_color.symbol .. " ",
+            fgd = util.strrep(sym_color.color.blit_fgd, 3),
+            bkg = util.strrep(sym_color.color.blit_bkg, 3)
+        })
+    end
+
+    -- write label and initial indicator light
+    e.window.setCursorPos(5, 1)
+    e.window.write(args.label)
+
+    -- on state change
+    ---@param new_state integer indicator state
+    function e.on_update(new_state)
+        local blit_cmd = state_blit_cmds[new_state]
+        e.window.setCursorPos(1, 1)
+        e.window.blit(blit_cmd.text, blit_cmd.fgd, blit_cmd.bkg)
+    end
+
+    -- initial icon draw
+    e.on_update(args.value or 1)
+
+    return e.get()
+end
+
+return icon