local nk = require("nakama")
local utils = require("lua.utils")

local daily_rewards = {}

function daily_rewards.rpc_claim_daily_reward(context, payload)
    if not context.user_id then error("Not authenticated") end

    local now = os.date("!*t")
    local currentMonth = string.format("%02d", now.month)
    local todayStr = string.format("%04d-%02d-%02d", now.year, now.month, now.day)
    local todayIndex = now.day - 1 -- 0 to 30

    local stateObjs = nk.storage_read({{ collection = "daily_rewards", key = "state", user_id = context.user_id }})
    local state = { claimed_days = {}, last_claim_date = "", month = "" }
    
    if stateObjs and #stateObjs > 0 then
        local val = stateObjs[1].value
        state.last_claim_date = val.last_claim_date or ""
        state.month = val.month or ""
        
        if type(val.claimed_days) == "number" then
            for i = 0, val.claimed_days - 1 do
                table.insert(state.claimed_days, i)
            end
        elseif type(val.claimed_days) == "table" then
            state.claimed_days = val.claimed_days
        end
    end

    if state.month ~= currentMonth then
        state.claimed_days = {}
        state.month = currentMonth
    end

    if state.last_claim_date == todayStr then
        error("Already claimed today")
    end

    local configObjs = nk.storage_read({{ collection = "config", key = "daily_rewards", user_id = "00000000-0000-0000-0000-000000000000" }})
    local config = {}
    if configObjs and #configObjs > 0 then
        config = configObjs[1].value
    end

    local monthRewards = config[currentMonth]
    if not monthRewards or #monthRewards == 0 then
        monthRewards = {}
        for i = 0, 30 do
            table.insert(monthRewards, { type = "star", amount = math.min(10 + i * 5, 100) })
        end
    end

    local dayIndex = todayIndex
    -- In lua array size is #monthRewards
    if dayIndex >= #monthRewards then
        error("Already claimed all rewards for this month")
    end
    
    local hasClaimed = false
    for _, claimed_day in ipairs(state.claimed_days) do
        if claimed_day == dayIndex then
            hasClaimed = true
            break
        end
    end

    if hasClaimed then
        error("Already claimed today's reward")
    end

    -- Lua arrays are 1-indexed!
    local rewardData = monthRewards[dayIndex + 1]
    if type(rewardData) == "number" then
        rewardData = { type = "star", amount = rewardData }
    end

    local rewardType = rewardData.type or "star"
    local rewardAmount = rewardData.amount or 0

    if rewardType == "star" or rewardType == "gold" then
        local changes = {}
        changes[rewardType] = rewardAmount
        nk.wallet_update(context.user_id, changes, {}, true)
    elseif string.sub(rewardType, 1, 5) == "frag_" then
        local invObjs = nk.storage_read({{ collection = "inventory", key = "fragments", user_id = context.user_id }})
        local frags = {}
        if invObjs and #invObjs > 0 then
            frags = invObjs[1].value
        end
        frags[rewardType] = (frags[rewardType] or 0) + rewardAmount
        nk.storage_write({{
            collection = "inventory",
            key = "fragments",
            user_id = context.user_id,
            value = frags,
            permission_read = 1,
            permission_write = 0
        }})
    end

    table.insert(state.claimed_days, dayIndex)
    state.last_claim_date = todayStr

    nk.storage_write({{
        collection = "daily_rewards",
        key = "state",
        user_id = context.user_id,
        value = state,
        permission_read = 1,
        permission_write = 0
    }})

    return nk.json_encode({ success = true, reward_type = rewardType, reward_amount = rewardAmount, day = dayIndex + 1 })
end

function daily_rewards.rpc_get_daily_reward_state(context, payload)
    if not context.user_id then error("Not authenticated") end

    local now = os.date("!*t")
    local currentMonth = string.format("%02d", now.month)
    local todayStr = string.format("%04d-%02d-%02d", now.year, now.month, now.day)
    local todayIndex = now.day - 1

    local stateObjs = nk.storage_read({{ collection = "daily_rewards", key = "state", user_id = context.user_id }})
    local state = { claimed_days = {}, last_claim_date = "", month = "" }
    if stateObjs and #stateObjs > 0 then
        local val = stateObjs[1].value
        state.last_claim_date = val.last_claim_date or ""
        state.month = val.month or ""
        if type(val.claimed_days) == "number" then
            for i = 0, val.claimed_days - 1 do
                table.insert(state.claimed_days, i)
            end
        elseif type(val.claimed_days) == "table" then
            state.claimed_days = val.claimed_days
        end
    end
    if state.month ~= currentMonth then
        state.claimed_days = {}
        state.month = currentMonth
    end

    local configObjs = nk.storage_read({{ collection = "config", key = "daily_rewards", user_id = "00000000-0000-0000-0000-000000000000" }})
    local config = {}
    if configObjs and #configObjs > 0 then
        config = configObjs[1].value
    end
    local monthRewards = config[currentMonth]
    if not monthRewards or #monthRewards == 0 then
        monthRewards = {}
        for i = 0, 30 do
            table.insert(monthRewards, { type = "star", amount = math.min(10 + i * 5, 100) })
        end
    end

    local hasClaimedToday = false
    for _, claimed_day in ipairs(state.claimed_days) do
        if claimed_day == todayIndex then hasClaimedToday = true break end
    end

    local canClaimToday = (state.last_claim_date ~= todayStr) and (not hasClaimedToday) and (todayIndex < #monthRewards)

    return nk.json_encode({
        state = state,
        month_rewards = monthRewards,
        can_claim_today = canClaimToday,
        today_date = todayStr,
        today_index = todayIndex,
        server_month = now.month
    })
end

function daily_rewards.rpc_set_daily_reward_config(context, payload)
    utils.require_admin(context)
    local request = nk.json_decode(payload or "{}")
    nk.storage_write({{
        collection = "config",
        key = "daily_rewards",
        user_id = "00000000-0000-0000-0000-000000000000",
        value = request.config,
        permission_read = 2,
        permission_write = 0
    }})
    return nk.json_encode({ success = true })
end

function daily_rewards.rpc_get_daily_reward_config_admin(context, payload)
    utils.require_admin(context)
    local configObjs = nk.storage_read({{ collection = "config", key = "daily_rewards", user_id = "00000000-0000-0000-0000-000000000000" }})
    local config = {}
    if configObjs and #configObjs > 0 then
        config = configObjs[1].value
    end
    return nk.json_encode({ config = config })
end

nk.register_rpc(daily_rewards.rpc_claim_daily_reward, "claim_daily_reward")
nk.register_rpc(daily_rewards.rpc_get_daily_reward_state, "get_daily_reward_state")
nk.register_rpc(daily_rewards.rpc_set_daily_reward_config, "set_daily_reward_config")
nk.register_rpc(daily_rewards.rpc_get_daily_reward_config_admin, "get_daily_reward_config_admin")

nk.logger_info("LUA TEST: daily rewards module loaded")

return daily_rewards