package mysql

import (
	"context"
	"database/sql"
	"errors"
	"strconv"
	"strings"

	"hyapp/pkg/appcode"
	"hyapp/pkg/xerr"
	"hyapp/services/wallet-service/internal/domain/ledger"
)

const (
	// charge_amount 是 ca15f098 上线时的兼容口径：Agency 比例直接作用于礼物实扣金额，
	// 因而主播比例与 Agency 比例必须共同受 100% 资金池约束。
	agencyPointShareBaseChargeAmount = "charge_amount"
	// host_income 表示平台在主播本次实际 POINT 收益之外追加 Agency 奖励。
	// 该口径先完成礼物类型和主播政策换算，再对最终主播收益取比例，允许出现 100%+20%。
	agencyPointShareBaseHostIncome = "host_income"
)

type walletPolicyInstance struct {
	InstanceCode             string
	TemplateCode             string
	TemplateVersion          string
	RegionID                 int64
	HostPointAsset           string
	HostPointRatioPPM        int64
	HostGiftTypeRatioEnabled bool
	AgencyPointRatioPPM      int64
	AgencyPointShareBase     string
	PointsPerUSD             int64
	WithdrawFeeBPS           int64
}

func (r *Repository) resolveActiveWalletPolicy(ctx context.Context, tx *sql.Tx, appCode string, regionID int64, nowMS int64) (walletPolicyInstance, bool, error) {
	appCode = appcode.Normalize(appCode)
	if regionID < 0 {
		return walletPolicyInstance{}, false, xerr.New(xerr.InvalidArgument, "region_id is invalid")
	}
	row := tx.QueryRowContext(ctx, `
		SELECT instance_code, template_code, template_version, region_id, host_point_asset_type,
		       host_point_ratio_ppm,
		       COALESCE(JSON_UNQUOTE(JSON_EXTRACT(rule_json, '$.host.use_gift_type_ratio')), 'false'),
		       agency_point_ratio_ppm,
		       COALESCE(JSON_UNQUOTE(JSON_EXTRACT(rule_json, '$.agency.share_base')), 'charge_amount'),
		       points_per_usd, withdraw_fee_bps
		FROM wallet_policy_instances
		WHERE app_code = ?
		  AND region_id IN (?, 0)
		  AND status = 'active'
		  AND effective_from_ms <= ?
		  AND (effective_to_ms = 0 OR effective_to_ms > ?)
		ORDER BY CASE WHEN region_id = ? THEN 0 ELSE 1 END, published_at_ms DESC, instance_code DESC
		LIMIT 1`,
		appCode, regionID, nowMS, nowMS, regionID,
	)
	var item walletPolicyInstance
	var hostGiftTypeRatioRaw string
	if err := row.Scan(
		&item.InstanceCode,
		&item.TemplateCode,
		&item.TemplateVersion,
		&item.RegionID,
		&item.HostPointAsset,
		&item.HostPointRatioPPM,
		&hostGiftTypeRatioRaw,
		&item.AgencyPointRatioPPM,
		&item.AgencyPointShareBase,
		&item.PointsPerUSD,
		&item.WithdrawFeeBPS,
	); err != nil {
		if errors.Is(err, sql.ErrNoRows) {
			return walletPolicyInstance{}, false, nil
		}
		return walletPolicyInstance{}, false, err
	}
	item.HostPointAsset = strings.ToUpper(strings.TrimSpace(item.HostPointAsset))
	if item.HostPointAsset == "" {
		item.HostPointAsset = ledger.AssetPoint
	}
	parsedGiftTypeRatio, err := strconv.ParseBool(strings.ToLower(strings.TrimSpace(hostGiftTypeRatioRaw)))
	if err != nil {
		return walletPolicyInstance{}, false, xerr.New(xerr.InvalidArgument, "wallet policy host gift type ratio flag is invalid")
	}
	item.HostGiftTypeRatioEnabled = parsedGiftTypeRatio
	item.AgencyPointShareBase = strings.ToLower(strings.TrimSpace(item.AgencyPointShareBase))
	if item.AgencyPointShareBase == "" {
		item.AgencyPointShareBase = agencyPointShareBaseChargeAmount
	}
	if item.HostPointAsset != ledger.AssetPoint ||
		item.HostPointRatioPPM <= 0 || item.HostPointRatioPPM > 1_000_000 ||
		item.AgencyPointRatioPPM < 0 || item.AgencyPointRatioPPM > 1_000_000 ||
		item.PointsPerUSD <= 0 || item.WithdrawFeeBPS < 0 || item.WithdrawFeeBPS > 10_000 {
		return walletPolicyInstance{}, false, xerr.New(xerr.InvalidArgument, "wallet policy instance is invalid")
	}
	switch item.AgencyPointShareBase {
	case agencyPointShareBaseChargeAmount:
		// 旧实例没有 share_base，必须继续执行原先的总资金池守恒约束；否则一次重新发布就会
		// 把历史 70%+20% 配置悄然解释成可超发政策。
		if item.HostPointRatioPPM+item.AgencyPointRatioPPM > 1_000_000 {
			return walletPolicyInstance{}, false, xerr.New(xerr.InvalidArgument, "wallet policy instance is invalid")
		}
	case agencyPointShareBaseHostIncome:
		// host_income 是额外平台奖励，Agency 百分比相对于主播实际到账值独立校验，不能与
		// host_point_ratio_ppm 相加后套用旧的 100% 上限。
	default:
		return walletPolicyInstance{}, false, xerr.New(xerr.InvalidArgument, "wallet policy agency share base is invalid")
	}
	return item, true, nil
}