cc-mek-scada/graphics/elements/indicators/hbar.lua

123 lines
3.5 KiB
Lua

-- Horizontal Bar Graphics Element
local util = require("scada-common.util")
local element = require("graphics.element")
---@class hbar_args
---@field show_percent? boolean whether or not to show the percent
---@field bar_fg_bg? cpair bar foreground/background colors if showing percent
---@field parent graphics_element
---@field id? string element id
---@field x? integer 1 if omitted
---@field y? integer 1 if omitted
---@field width? integer parent width if omitted
---@field height? integer parent height if omitted
---@field gframe? graphics_frame frame instead of x/y/width/height
---@field fg_bg? cpair foreground/background colors
-- new horizontal bar
---@param args hbar_args
---@return graphics_element element, element_id id
local function hbar(args)
-- properties/state
local last_num_bars = -1
-- create new graphics element base object
local e = element.new(args)
-- bar width is width - 5 characters for " 100%" if showing percent
local bar_width = util.trinary(args.show_percent, e.frame.w - 5, e.frame.w)
assert(bar_width > 0, "graphics.elements.indicators.hbar: too small for bar")
-- determine bar colors
local bar_bkg = e.fg_bg.blit_bkg
local bar_fgd = e.fg_bg.blit_fgd
if args.bar_fg_bg ~= nil then
bar_bkg = args.bar_fg_bg.blit_bkg
bar_fgd = args.bar_fg_bg.blit_fgd
end
-- handle data changes
---@param fraction number 0.0 to 1.0
function e.on_update(fraction)
e.value = fraction
-- enforce minimum and maximum
if fraction < 0 then
fraction = 0.0
elseif fraction > 1 then
fraction = 1.0
end
-- compute number of bars
local num_bars = util.round(fraction * (bar_width * 2))
-- redraw bar if changed
if num_bars ~= last_num_bars then
last_num_bars = num_bars
local fgd = ""
local bkg = ""
local spaces = ""
-- fill percentage
for _ = 1, num_bars / 2 do
spaces = spaces .. " "
fgd = fgd .. bar_fgd
bkg = bkg .. bar_bkg
end
-- add fractional bar if needed
if num_bars % 2 == 1 then
spaces = spaces .. "\x95"
fgd = fgd .. bar_bkg
bkg = bkg .. bar_fgd
end
-- pad background
for _ = 1, ((bar_width * 2) - num_bars) / 2 do
spaces = spaces .. " "
fgd = fgd .. bar_bkg
bkg = bkg .. bar_bkg
end
-- draw bar
for y = 1, e.frame.h do
e.window.setCursorPos(1, y)
-- intentionally swapped fgd/bkg since we use spaces as fill, but they are the opposite
e.window.blit(spaces, bkg, fgd)
end
end
-- update percentage
if args.show_percent then
e.window.setCursorPos(bar_width + 2, math.max(1, math.ceil(e.frame.h / 2)))
e.window.write(util.sprintf("%3.0f%%", fraction * 100))
end
end
-- change bar color
---@param bar_fg_bg cpair new bar colors
function e.recolor(bar_fg_bg)
bar_bkg = bar_fg_bg.blit_bkg
bar_fgd = bar_fg_bg.blit_fgd
-- re-draw
last_num_bars = 0
e.on_update(e.value)
end
-- set the percentage value
---@param val number 0.0 to 1.0
function e.set_value(val) e.on_update(val) end
-- initialize to 0
e.on_update(0)
return e.get()
end
return hbar