【数据存储】货币钱包：金币与元宝的分账存储设计

-- 货币钱包：分账结构
local COINS = {"gold", "yuanbao", "bindyb"}
local function walletBalance(player, coin)
    return tonumber(getplayvar(player, "HUMAN", "Wallet_" .. coin) or 0)
end
local function walletSeq(player, coin)
    return tonumber(getplayvar(player, "HUMAN", "WalletSeq_" .. coin) or 0)
end
local function balanceOf(player)
    local parts = {}
    for _, c in ipairs(COINS) do
        parts[#parts + 1] = c .. "=" .. walletBalance(player, c) .. "#" .. walletSeq(player, c)
    end
    return table.concat(parts, "|")
end

-- 转账记账：流水成对核销
local player = class(actor)
local flowSeq = 0
local function transferCoin(player, fromCoin, toCoin, amount)
    local fromBal = walletBalance(player, fromCoin)
    if fromBal < amount then
        sendmsg(player, 1, 0, "余额不足，" .. fromCoin .. " 还差 " .. amount - fromBal .. "。")
        return false
    end
    flowSeq = flowSeq + 1
    local flowNo = "F" .. os.date("%Y%m%d") .. "_" .. flowSeq
    setplayvar(player, "HUMAN", "Wallet_" .. fromCoin, fromBal - amount, true)
    setplayvar(player, "HUMAN", "WalletSeq_" .. fromCoin, walletSeq(player, fromCoin) + 1, true)
    setplayvar(player, "HUMAN", "FlowLog", (getplayvar(player, "HUMAN", "FlowLog") or "")
        .. flowNo .. "|" .. fromCoin .. ":-" .. amount .. ";", true)
    setplayvar(player, "HUMAN", "Wallet_" .. toCoin, walletBalance(player, toCoin) + amount, true)
    return true
end