local ns = firefly

--minetest.register_entity(":firefly:beacon", {
--    initial_properties = {
--        visual = "sprite",
--        textures = {"blank.png"},
--        static_save = false,
--    },
--    time = 0,
--    on_step = function(e)
--        local time = minetest.get_us_time()
--        if time -e.time > 1000000 then
--            e.delegate:check_nearby()
--            e.time = time
--        end
--    end,
--})

local beacons = {}

local MAX_LOYALTY = 10

local Beacon
Beacon = {
    init = function(game, pos, team)
        local e = {
            id = "beacon_"..minetest.get_us_time().."_"..math.random(1, 1000000),
            game = game,
            pos = game.map.pos +pos,
            team = team or "__neutral",
            loyalty = MAX_LOYALTY,
            nearby = {},
        }
        setmetatable(e, Beacon)
        
        beacons[e.id] = e
        
        e:rebuild()
        
        e._timer = function() e:check_nearby() end
        ns.timer:listen("every_second", e._timer)
        
--        minetest.set_node(e.pos, {name = "beacon"})
--        minetest.get_meta(e.pos):set_string("beacon", e.id)
--        minetest.get_node_timer(e.pos):start(1)
        
        return e
    end,
    deinit = function(e)
        ns.timer:unlisten("every_second", e._timer)
        beacons[e.id] = nil
    end,
    rebuild = function(e)
        for x = e.pos.x -1, e.pos.x +1 do
            for z = e.pos.z -1, e.pos.z +1 do
                minetest.set_node(vector.new(x, e.pos.y -1, z), {name = "colored_glass", param2 = e.team == "__neutral" and 0 or e.team == "red" and 1 or 2})
            end
        end
    end,
    check_nearby = function(e)
        local team = e.game.teams[e.team]
        
        -- Give score to the controlling team, if there is one.
        if team then
            e.game:add_score(e.team, 1)
        end
        
        local not_nearby = table.copy(e.nearby)
        local enemies_near = {}
        local ally_near
        for _, m in pairs(ns.players) do
            if ns.manhattan_distance(m.pos, e.pos) < 3 then
                if not e.nearby[m.name] then
                    ns.add_hud_bar(m, "beacon_status", {
                        max = MAX_LOYALTY,
                        min = 0,
                        title = "Beacon",
                        -- Charge-down if we are controlled by someone, but charge-up if contested.
                        value = e.team == "__neutral" and MAX_LOYALTY -e.loyalty or e.loyalty,
                        color = e.team == "__neutral" and "#fff" or e.game.teams[e.team].color,
                    })
                end
                e.nearby[m.name] = true
                not_nearby[m.name] = nil
                if m.team ~= e.team then
                    table.insert(enemies_near, m)
                else
                    ally_near = true
                end
            end
        end
        
        for name in pairs(not_nearby) do
            e.nearby[name] = nil
            ns.remove_hud_bar(ns.players[name], "beacon_status")
        end
        
        -- If an enemy is near, weaken our team loyalty (but not if someone from out team is also near).
        if #enemies_near > 0 and not ally_near then
            -- Interference from competing enemy teams will also prevent us from losing loyalty, if we are contested.
            local team
            if e.team == "__neutral" then
                for i = 1, #enemies_near do
                    local m = enemies_near[i]
                    if team and m.team ~= team then
                        team = nil
                        break
                    end
                    team = m.team
                end
                if team then
                    e:set_loyalty(e.loyalty -1)
                end
            -- Otherwise, we only care that at least one enemy is near.
            else
                e:set_loyalty(e.loyalty -1)
            end
            
            -- If this dropped our loyalty to zero, we must switch teams.
            if e.loyalty <= 0 then
                e:switch_team(team)
            end
        -- If no enemies are near, we can rebuild loyalty.
        elseif e.loyalty < MAX_LOYALTY then
            -- Loyalty is rebuilt faster if an ally is near.
            e:set_loyalty(e.loyalty +(ally_near and 2 or 1))
        end
    end,
    set_loyalty = function(e, value)
        e.loyalty = value
        -- Update the status bar seen by nearby players.
        for name in pairs(e.nearby) do
            ns.change_hud_bar(ns.players[name], "beacon_status",{
                value = e.team == "__neutral" and MAX_LOYALTY -e.loyalty or e.loyalty,
            })
        end
    end,
    switch_team = function(e, team)
        -- If we are switching from a non-contested state, we must enter a contested state before we can be assigned a new team.
        if team and e.team ~= "__neutral" then
            team = "__neutral"
        end
        
        -- If we didn't get a team, we weren't contested, but should be.
        e.team = team or "__neutral"
        
        -- Reset our loyalty.
        e.loyalty = MAX_LOYALTY
        
        -- We don't use set_loyalty to update the status bar because we also change the color.
        for name in pairs(e.nearby) do
            ns.change_hud_bar(ns.players[name], "beacon_status", {
                value = e.team == "__neutral" and MAX_LOYALTY -e.loyalty or e.loyalty,
                color = e.team == "__neutral" and "#fff" or e.game.teams[e.team].color or "#48d",
            })
        end
        
        e:rebuild()
    end,
}
Beacon.__index = Beacon

return Beacon