local log  = require("scada-common.log")
local util = require("scada-common.util")

local displaybox = require("graphics.elements.displaybox")
local structs    = require("graphics.structs")

local renderer = {}

local gconf = {
    -- root boxes
    root = {
        fgd = colors.black,
        bkg = colors.lightGray
    }
}

-- render engine
local engine = {
    monitors = nil,
    dmesg_window = nil
}

-- UI elements
local ui = {
    main_box = nil,
    unit_boxes = {}
}

-- reset a display to the "default", but set text scale to 0.5
local function _reset_display(monitor)
    monitor.setTextScale(0.5)
    monitor.setTextColor(colors.white)
    monitor.setBackgroundColor(colors.black)
    monitor.clear()
    monitor.setCursorPos(1, 1)
end

-- link to the monitor peripherals
---@param monitors monitors_struct
function renderer.set_displays(monitors)
    engine.monitors = monitors
end

-- reset all displays in use by the renderer
function renderer.reset()
    -- reset primary monitor
    _reset_display(engine.monitors.primary)

    -- reset unit displays
    for _, monitor in pairs(engine.monitors.unit_displays) do
        _reset_display(monitor)
    end
end

-- initialize the dmesg output window
function renderer.init_dmesg()
    local disp_x, disp_y = engine.monitors.primary.getSize()
    engine.dmesg_window = window.create(engine.monitors.primary, 1, 1, disp_x, disp_y)

    log.direct_dmesg(engine.dmesg_window)
end

-- start the coordinator GUI
function renderer.start_ui()
    local palette = structs.graphics.cpair(gconf.root.fgd, gconf.root.bkg)

    ui.main_box = displaybox{window = engine.monitors.primary, fg_bg = palette}

    for _, monitor in pairs(engine.monitors.unit_displays) do
        table.insert(ui.unit_boxes, displaybox{window = engine.monitors.primary, fg_bg = palette})
    end
end

-- close out the UI
function renderer.close_ui()
    -- clear root UI elements
    ui.main_box = nil
    ui.unit_boxes = {}
end

return renderer