TextDisplay.lua

TextDisplay = {}

---Replaces all instances of the keys of the provided map with the values in the provided map
---@param s string string to replace values in
---@param map table map of values to replace, where keys are replaced by values
---@return string s the resulting substituted string
local function replaceSymbols(s, map)
    for key, value in pairs(map) do
        s = s:gsub(key, value)
    end

    return s
end

-- this function works by iterating over all of the items in the provided indicatordata table and substituting
-- them in for each line according to their x and y values

---Gets the display lines for a DCS display
---@param dcsDisplay table The DCS display to parse
---@param width number The character width of the screen
---@param height number The lines of text the screen supports
---@param displayIndicatorData table The data from the json file containing information about the display
---@param getDisplayPage function Gets the current display page
---@param replaceSymbolMap table Map of symbols to replace from -> to
---@return table displayLines The lines of the display
function TextDisplay.GetDisplayLines(dcsDisplay, width, height, displayIndicatorData, getDisplayPage, replaceSymbolMap)
    local emptyLine = string.rep(" ", width)

    local displayLines = {}
    for i=1,height do
        displayLines[i] = emptyLine
    end
    if not dcsDisplay then
        return displayLines
    end

    local displayPage = getDisplayPage()

    for k, v in pairs(dcsDisplay) do
        local candidates = displayIndicatorData[k]
        if candidates then
            if replaceSymbolMap then
                v = replaceSymbols(v, replaceSymbolMap)
            end
            local render_instructions = nil
            if #candidates == 1 then
                render_instructions = candidates[1]
            else
                for _, ri in pairs(candidates) do
                    for _, page in pairs(ri.pages) do
                        if displayPage == page then
                            render_instructions = ri
                            break
                        end
                    end
                end
            end
            if render_instructions then
                local ri = render_instructions
                local old_line = displayLines[ri.y]
                local replacements = {}
                if not ri.alignment or ri.alignment == "LFT" then
                    for i = 1, v:len(), 1 do
                        local c = v:sub(i,i)
                        if c ~= " " then replacements[ri.x + i - 1] = c end
                    end
                elseif ri.alignment == "RGHT" then
                    for i = 1, v:len(), 1 do
                        local c = v:sub(i,i)
                        if c ~= " " then replacements[ri.x - (v:len() - i)] = c end
                    end
                end
                local new_line = ""
                for i = 1, width, 1 do
                    new_line = new_line .. (replacements[i] or old_line:sub(i,i))
                end
                displayLines[ri.y] = new_line
            end
        end
    end

    return displayLines
end