ComfyFactorio/modules/scrap_towny_ffa/slots.lua

local table_size = table.size

local Table = require 'modules.scrap_towny_ffa.table'

-- called whenever a player places an item
local function on_built_entity(event)
    local ffatable = Table.get_table()
    local entity = event.created_entity
    if not entity.valid then
        return
    end
    if entity.name ~= 'laser-turret' then
        return
    end
    local player = game.players[event.player_index]
    local force = player.force
    local town_center = ffatable.town_centers[force.name]
    local surface = entity.surface
    if force == game.forces['player'] or force == game.forces['rogue'] or town_center == nil then
        surface.create_entity(
            {
                name = 'flying-text',
                position = entity.position,
                text = 'You are not acclimated to this technology!',
                color = {r = 0.77, g = 0.0, b = 0.0}
            }
        )
        player.insert({name = 'laser-turret', count = 1})
        entity.destroy()
        return
    end
    local slots = town_center.upgrades.laser_turret.slots
    local locations = town_center.upgrades.laser_turret.locations
    if table_size(locations) >= slots then
        surface.create_entity(
            {
                name = 'flying-text',
                position = entity.position,
                text = 'You do not have enough slots!',
                color = {r = 0.77, g = 0.0, b = 0.0}
            }
        )
        player.insert({name = 'laser-turret', count = 1})
        entity.destroy()
        return
    end
    local position = entity.position
    local key = tostring('{' .. position.x .. ',' .. position.y .. '}')
    locations[key] = true
end

-- called whenever a player places an item
local function on_robot_built_entity(event)
    local ffatable = Table.get_table()
    local entity = event.created_entity
    if not entity.valid then
        return
    end
    if entity.name ~= 'laser-turret' then
        return
    end
    local robot = event.robot
    local force = robot.force
    local town_center = ffatable.town_centers[force.name]
    local surface = entity.surface
    if force == game.forces['player'] or force == game.forces['rogue'] or town_center == nil then
        surface.create_entity(
            {
                name = 'flying-text',
                position = entity.position,
                text = 'Robot not acclimated to this technology!',
                color = {r = 0.77, g = 0.0, b = 0.0}
            }
        )
        robot.insert({name = 'laser-turret', count = 1})
        entity.destroy()
        return
    end
    local slots = town_center.upgrades.laser_turret.slots
    local locations = town_center.upgrades.laser_turret.locations
    if table_size(locations) >= slots then
        surface.create_entity(
            {
                name = 'flying-text',
                position = entity.position,
                text = 'Town does not have enough slots!',
                color = {r = 0.77, g = 0.0, b = 0.0}
            }
        )
        robot.insert({name = 'laser-turret', count = 1})
        entity.destroy()
        return
    end
    local position = entity.position
    local key = tostring('{' .. position.x .. ',' .. position.y .. '}')
    locations[key] = true
end

-- called whenever a player mines an entity but before it is removed from the map
-- will have the contents of the drops
local function on_player_mined_entity(event)
    local ffatable = Table.get_table()
    local player = game.players[event.player_index]
    local force = player.force
    local entity = event.entity
    if entity.name == 'laser-turret' then
        local town_center = ffatable.town_centers[force.name]
        if force == game.forces['player'] or force == game.forces['rogue'] or town_center == nil then
            return
        end
        local locations = town_center.upgrades.laser_turret.locations
        local position = entity.position
        local key = tostring('{' .. position.x .. ',' .. position.y .. '}')
        locations[key] = nil
    end
end

local Event = require 'utils.event'
Event.add(defines.events.on_built_entity, on_built_entity)
Event.add(defines.events.on_robot_built_entity, on_robot_built_entity)
Event.add(defines.events.on_player_mined_entity, on_player_mined_entity)