using dodohold.core;
using System.Globalization;

namespace molilian.core
{
    public partial class OverrideRuleCore
    {
        // KEYS: 小时触发、日触发、小时重写、日重写。沿用现有 key，保留历史数据。
        // 同一脚本内检查两项额度并更新计数，避免并发超额或只扣掉其中一项额度。
        private const string RecordRewriteScript = @"
local hourlyRewrites = tonumber(redis.call('GET', KEYS[3]) or '0')
local dailyRewrites = tonumber(redis.call('GET', KEYS[4]) or '0')
local hourlyLimit = tonumber(ARGV[1])
local dailyLimit = tonumber(ARGV[2])

redis.call('INCR', KEYS[1])
redis.call('EXPIRE', KEYS[1], 7200)
redis.call('INCR', KEYS[2])
redis.call('EXPIRE', KEYS[2], 259200)

if (hourlyLimit > 0 and hourlyRewrites >= hourlyLimit)
    or (dailyLimit > 0 and dailyRewrites >= dailyLimit) then
    return 0
end

redis.call('INCR', KEYS[3])
redis.call('EXPIRE', KEYS[3], 15552000)
redis.call('INCR', KEYS[4])
redis.call('EXPIRE', KEYS[4], 15552000)
return 1";

        private static string[] GetCounterKeys(OverrideRuleDTO rule, DateTime now) =>
        [
            $":override_rule_calls:{rule.id}:{now:yyyyMMddHH}",
            $":override_rule_calls:{rule.id}:{now:yyyyMMdd}",
            $":keyword_stats:{rule.platform}:{rule.id}:{now:yyyyMMddHH}",
            $":keyword_stats:{rule.platform}:{rule.id}:{now:yyyyMMdd}"
        ];

        private static async Task<bool> TryRecordRewriteAsync(OverrideRuleDTO rule, DateTime now)
        {
            try
            {
                // RedisUtility 与 RedisKit 均使用 RedisConfig，复用已初始化的连接池。
                // CSRedis 高层 Eval 仅支持一个 key；这里通过原生接口显式传入全部四个 key。
                var pool = RedisHelper.Instance.Nodes.Values.Single();
                var connection = await pool.GetAsync();
                Exception? error = null;
                try
                {
                    var keys = GetCounterKeys(rule, now).Select(key => pool.Prefix + key).ToArray();
                    var result = await connection.Value.EvalAsync(RecordRewriteScript, keys,
                        rule.hourly_calls_limit, rule.daily_calls_limit);
                    return Convert.ToInt64(result, CultureInfo.InvariantCulture) == 1;
                }
                catch (Exception ex)
                {
                    error = ex;
                    throw;
                }
                finally
                {
                    pool.Return(connection, error);
                }
            }
            catch (Exception ex)
            {
                _ = new LoggerLibrary("OverrideRule", "Redis")
                    .Info($"Rewrite limit check failed: {ex.Message}", ex.StackTrace).SaveAsync();
                // 无法确认额度时跳过受限规则；无限额规则保留统计故障时继续工作的行为。
                return rule.hourly_calls_limit <= 0 && rule.daily_calls_limit <= 0;
            }
        }

        public static async Task LoadStatisticsAsync(OverrideRuleDTO rule, DateTime now)
        {
            var counts = await RedisHelper.MGetAsync<int>(GetCounterKeys(rule, now));
            rule.current_hourly_calls = counts[0];
            rule.current_daily_calls = counts[1];
            rule.current_hourly_rewrites = counts[2];
            rule.current_daily_rewrites = counts[3];
        }
    }
}