local loadout_switcher        = {}

local string_find             = string.find
local string_gsub             = string.gsub
local string_match            = string.match
local math_random             = math.random
local math_ceil               = math.ceil
local player                  = require("player")
local require_loadout_num     = nil
local doneCallback            = nil
local timeout_timer           = 0
local timeout_active          = false
local timeout_max             = 30
local click_delay_min         = 0
local click_delay_max         = 0
local click_delay_remaining   = 0

local slots = {
    14, 15, 16,
    23, 24, 25,
    32, 33, 34,
    41, 42, 43,
}

local function cleanup()
    timeout_active = false
    click_delay_remaining = 0
    unregisterClientTick(tickerInventory)
    unregisterClientTick(timeoutTicker)
    require_loadout_num = nil
end

local function stripMinecraftColors(text)
    return string_gsub(text, "§.", "")
end

local function timeoutCallback()
    if timeout_active then
        local title = player.inventory.getChestTitle()
        if title and string_find(stripMinecraftColors(title), "Loadouts") then
            player.inventory.closeScreen()
        end

        if doneCallback then
            doneCallback(nil, false)
        end
        cleanup()
    end
end

local function timeoutTicker()
    if timeout_active then
        timeout_timer = timeout_timer + 1
        if timeout_timer >= timeout_max then
            timeoutCallback()
        end
    end
end

local function setClickDelay()
    if click_delay_min > 0 and click_delay_max > 0 then
        click_delay_remaining = math_random(click_delay_min, click_delay_max)
    end
end

local function tickerInventory()
    if click_delay_remaining > 0 then
        click_delay_remaining = click_delay_remaining - 1
        return
    end

    local title = player.inventory.getChestTitle()
    if not title then return end
    local clean_title = stripMinecraftColors(title)
    if not string_find(clean_title, "Loadouts") then return end
    if not require_loadout_num then return end

    local current_page = tonumber(string_match(clean_title, "(%d+)/"))
    local target_page = math_ceil(require_loadout_num / 12)

    if current_page and current_page ~= target_page then
        local search = current_page < target_page and "Next Page" or "Previous Page"
        local total_slots = player.inventory.getContainerSlots()
        for slot = 0, total_slots - 1 do
            local item = player.inventory.getStackFromContainer(slot)
            if item then
                local name = stripMinecraftColors(item.display_name)
                if string_find(name, search) then
                    player.inventory.leftClick(slot)
                    setClickDelay()
                    return
                end
            end
        end
        return
    end

    local target_name = "Loadout " .. tostring(require_loadout_num)
    for _, slot in ipairs(slots) do
        local item = player.inventory.getStackFromContainer(slot)
        if item then
            local name = stripMinecraftColors(item.display_name)
            if string_find(name, target_name) then
                player.inventory.leftClick(slot)
                player.inventory.closeScreen()
                if doneCallback then
                    doneCallback(require_loadout_num, true)
                end
                cleanup()
                return
            end
        end
    end
end

--- Equip a loadout by number.
--- @param loadout_num number Loadout number (1, 2, 3...).
--- @param callback function Callback function(loadout_num, success).
--- @param click_delay_min_ticks number Optional min ticks delay between GUI clicks.
--- @param click_delay_max_ticks number Optional max ticks delay between GUI clicks.
function loadout_switcher.equipLoadout(loadout_num, callback, click_delay_min_ticks, click_delay_max_ticks)
    unregisterClientTick(tickerInventory)
    unregisterClientTick(timeoutTicker)
    timeout_timer = 0
    timeout_active = false
    click_delay_remaining = 0

    if loadout_num then
        require_loadout_num = loadout_num
        doneCallback = callback
        click_delay_min = click_delay_min_ticks or 0
        click_delay_max = click_delay_max_ticks or 0
        setClickDelay()
        local max_page_navs = math_ceil(loadout_num / 12) - 1
        local max_with_delay = click_delay_max * (max_page_navs + 2)
        timeout_max = math.max(30, max_with_delay + 20)
        player.sendCommand("/loadout")
        timeout_active = true
        registerClientTick(tickerInventory)
        registerClientTick(timeoutTicker)
    end
end

return loadout_switcher