--
-- code review version. Thanks go to JK, KingRaptor, Jools
--
function gadget:GetInfo()
    return {
        name        = "feature placer v3",
        desc        = "Spawns Features and Units",
        author      = "Gnome, Smoth",
        date        = "August 2008, updated 7/11/2014",
        license     = "PD",
        layer       = 0,
        enabled     = true  --  loaded by default?
    }
end

-- these are here because I like the way they look
local   spSetUnitNeutral        = Spring.SetUnitNeutral
local   spSetUnitBlocking       = Spring.SetUnitBlocking
local   spSetUnitRotation       = Spring.SetUnitRotation
local   spSetUnitLosState       = Spring.SetUnitLosState
local   spSetUnitAlwaysVisible  = Spring.SetUnitAlwaysVisible
local   spCreateUnit            = Spring.CreateUnit
local   spGetGaiaTeamID         = Spring.GetGaiaTeamID
local   spCreateFeature         = Spring.CreateFeature
local   spGetGroundHeight       = Spring.GetGroundHeight
local   spEcho                  = Spring.Echo

-- SYNCED only
if not gadgetHandler:IsSyncedCode() then
    return
end

local   rotationMultiplier  = math.pi / 32768
local   gaiaTeamID          = spGetGaiaTeamID()
local   featureSetFile      = "config/featureconfig.lua"
local   losState            = {los=true, prevLos=true, contRadar=true, radar=true}
----------------------------------------------------
-- PARAMS
-- featureList = table of values to storing feature
--      name, location x, location z, rotation
--      Ex: {   name = 'artbushweird1lo',
--              x = 7847,
--              z = 4152,
--              rot = "0" },
----------------------------------------------------
function ProcessFeatures(featureList)
    spEcho("placing " .. #featureList .. " feature(s)")
    for _,fDef in pairs(featureList) do
        if FeatureDefNames[fDef.name] then
            local yPlacement    = spGetGroundHeight(fDef.x,fDef.z)+5
            spCreateFeature(fDef.name, fDef.x, yPlacement, fDef.z, fDef.rot)
        else
            spEcho("featureplacer warning: invalid feature name", fDef.name)
        end
    end
end

----------------------------------------------------
-- Places units
-- PARAMS
-- unitList = table of values to storing a unit
--      name, location x, location z, rotation
--      Ex: {   name = 'badger',
--              x = 7847,
--              z = 4152,
--              rot = "0" },
----------------------------------------------------
function ProcessUnits(unitList)
    spEcho("placing " .. #unitList .. " unit(s)")
    for _,uDef in pairs(unitList) do
        if UnitDefNames[uDef.name] then
            local unitId = spCreateUnit(uDef.name, uDef.x, 0, uDef.z, 0, gaiaTeamID)
            if unitId ~= nil then
                local unitRotation  = -uDef.rot * rotationMultiplier
                spSetUnitRotation(unitId, 0, unitRotation, 0)
                spSetUnitNeutral(unitId,true)
                spSetUnitBlocking(unitId,true)
                spSetUnitAlwaysVisible(unitId,true)
                spSetUnitLosState(unitId,0,losState)
                for _,allyTeam in ipairs(Spring.GetAllyTeamList()) do
                    Spring.SetUnitLosMask(unitId, allyTeam, {prevLos=true,})
                end
            end
        else
            spEcho("featureplacer warning: invalid unit def name", bDef.name)
        end
    end
end

----------------------------------------------------
-- Places neutral structures
-- PARAMS
-- buildingList = table of values to storing buidking
--      name, location x, location z, rotation
--      Ex: {   name = 'neutralfueltank1',
--              x = 7847,
--              z = 4152,
--              rot = "north" },
----------------------------------------------------
function ProcessBuildings(buildingList)
    spEcho("placing " .. #buildingList .. " building(s)")
    for _,bDef in pairs(buildingList) do
        if UnitDefNames[bDef.name] then
            local buildingId = spCreateUnit(bDef.name, bDef.x, 0, bDef.z, bDef.rot, gaiaTeamID)
            if buildingId ~= nil then
                spSetUnitNeutral(buildingId,true)
                spSetUnitBlocking(buildingId,true)
                spSetUnitAlwaysVisible(buildingId,true)
                spSetUnitLosState(buildingId,0,losState)
                for _,allyTeam in ipairs(Spring.GetAllyTeamList()) do
                    Spring.SetUnitLosMask(buildingId, allyTeam, {prevLos=true,})
                end
            end
        else
            spEcho("featureplacer warning: invalid building def name", bDef.name)
        end
    end
end

----------------------------------------------------
-- gadgethander:GamePreload
----------------------------------------------------
function gadget:GamePreload()
    if not VFS.FileExists(featureSetFile)   then
        spEcho("No feature placer objects loaded")
        return
    end

    featurecfg      = VFS.Include(featureSetFile)
    unitList        = featurecfg.unitlist
    featureList     = featurecfg.objectlist
    buildingList    = featurecfg.buildinglist

    if ( unitList ) then
        ProcessUnits(unitList)
    end
    if ( featureList )  then
        ProcessFeatures(featureList)
    end
    if ( buildingList ) then
        ProcessBuildings(buildingList)
    end
end