【框架设计】交易行指数：全服物价指数的计算框架

-- 交易行指数：样本采集
local player = class(actor)
local CORE_ITEMS = {["金创药"] = 1, ["强化石"] = 2, ["裁决之杖"] = 8}
local function addSample(player, itemName, dealPrice, dealCount)
    local weight = CORE_ITEMS[itemName]
    if weight == nil then return end
    local key = "IdxSample_" .. itemName
    setsysvarex(key, tonumber(getsysvar(key) or 0) + dealPrice * dealCount * weight, true)
    setsysvarex(key .. "_Cnt", tonumber(getsysvar(key .. "_Cnt") or 0) + dealCount * weight, true)
end

-- 交易行指数：每日计算
local player = class(actor)
local BASE_VALUE = 100
local function calcIndex(player)
    local totalValue, totalWeight = 0, 0
    for itemName, weight in pairs(CORE_ITEMS) do
        local sum = tonumber(getsysvar("IdxSample_" .. itemName) or 0)
        local cnt = tonumber(getsysvar("IdxSample_" .. itemName .. "_Cnt") or 1)
        if cnt > 0 then
            local avg = sum / cnt
            totalValue = totalValue + avg * weight
            totalWeight = totalWeight + weight
        end
    end
    local index = totalWeight > 0 and math.floor(totalValue / totalWeight) or BASE_VALUE
    setsysvarex("EcoIndex_" .. os.date("%Y%m%d"), index, true)
    sendmsg(player, 1, 0, "今日经济指数：" .. index .. "（基期 100）。")
end