Easier and smarter area unit reclaim orders, priority system by team and unitdef

cmd_improved_area_reclaim.lua

function widget:GetInfo()
	return {
		name = "Improved unit area reclaim",
		desc = "Easier and smarter area unit reclaim orders, priority system by team and unitdef",
		author = "Lexon",
		date = "17.07.2022",
        version = 1.1,
		license = "GNU GPL, v2 or later",
		layer = 10,
		enabled = true  --  loaded by default?
	}
end

local spGetUnitsInCylinder = Spring.GetUnitsInCylinder
local spGetFeaturesInCylinder = Spring.GetFeaturesInCylinder
local spGiveOrderToUnit = Spring.GiveOrderToUnit
local spGetSelectedUnits = Spring.GetSelectedUnits
local spGetUnitDefID = Spring.GetUnitDefID
local spGetUnitSeparation = Spring.GetUnitSeparation
local spGetUnitCommands = Spring.GetUnitCommands

local isImmobileBuilder = {}
for unitDefID, unitDef in pairs(UnitDefs) do
	if unitDef.isBuilder and not unitDef.canMove and not unitDef.isFactory then
		isImmobileBuilder[unitDefID] = true
	end
end

local function ContainsFightCMD(commands)
    for _, value in pairs(commands) do
        if value.id == CMD.FIGHT then
            return true
        end
    end
    return false
end

local function FilterByUnitDefID(list, id)
    for index, value in pairs(list) do
        if spGetUnitDefID(value) ~= id then
            list[index] = nil
        end
    end
    return list
end

function widget:CommandNotify(cmdID, cmdParams, _)
    -- Check if the command is a reclaim order
    if cmdID == CMD.RECLAIM then
        -- Check if the reclaim command is an area command (x, z, radius)
        if cmdParams[1] and cmdParams[3] and cmdParams[4] then
            local x, z, radius = cmdParams[1], cmdParams[3], cmdParams[4]

            --Skip if features/reclaim is present
            local features = spGetFeaturesInCylinder(x, z, radius)
            if features and #features > 1 then
                return false
            end

            local reclaimers = {}
            local unitDefIDTemp
            for _, reclaimerID in pairs(spGetSelectedUnits()) do
                unitDefIDTemp = spGetUnitDefID(reclaimerID)
                if UnitDefs[unitDefIDTemp].canReclaim then
                    reclaimers[reclaimerID] = unitDefIDTemp
                end
            end

            -- Get unit under mouse
            local targetDef = spGetUnitsInCylinder(x, z, 15)
            if targetDef[1] then
                targetDef = spGetUnitDefID(targetDef[1])
            else
                targetDef = nil
            end

            --Get enemy units first
            local units = spGetUnitsInCylinder(x, z, radius, Spring.ENEMY_UNITS)
            if targetDef then
                units = FilterByUnitDefID(units, targetDef)
            end

            --Get allied units if there are no enemy units
            if #units < 1 then
                units = spGetUnitsInCylinder(x, z, radius, Spring.MY_UNITS)
                if targetDef then
                    units = FilterByUnitDefID(units, targetDef)
                end
            end

            for reclaimerID, unitDefID in pairs(reclaimers) do
                for _, unitID in pairs(units) do
                    if isImmobileBuilder[unitDefID] and spGetUnitSeparation(reclaimerID, unitID, true) < UnitDefs[unitDefID].buildDistance then
                        -- Construction turrets are on fight command when idle
                        -- Inserting reclaim command, tried other nicer solutions but could not get them to work...
                        if ContainsFightCMD(spGetUnitCommands(reclaimerID, 2)) then
                            spGiveOrderToUnit(reclaimerID, CMD.INSERT, {0, CMD.RECLAIM, CMD.OPT_SHIFT, unitID}, {"alt"} )
                        else
                            spGiveOrderToUnit(reclaimerID, CMD.RECLAIM, {unitID}, {"shift"})
                        end
                    end
                    if not isImmobileBuilder[unitDefID] then
                        spGiveOrderToUnit(reclaimerID, CMD.RECLAIM, {unitID}, {"shift"})
                    end
                end
            end

            -- Block the original order, it does nothing and triggers UnitIdle for con turrets that replaces our given order with a fight command
            return true
        end
    end
end