package authz

import (
	"bssapp-backend/auth"
	"context"
	"fmt"
	"strings"
)

func BuildMSSQLPiyasaFilter(
	ctx context.Context,
	column string,
) string {
	claims, ok := auth.GetClaimsFromContext(ctx)
	if ok && claims != nil && claims.IsAdmin() {
		return "1=1"
	}

	codes := GetPiyasaCodesFromCtx(ctx)

	if len(codes) == 0 {
		return "1=0"

	}
	return BuildMSSQLPiyasaFilterWithCodes(column, codes)
}

func BuildMSSQLPiyasaFilterWithCodes(column string, codes []string) string {
	normalizedCol := fmt.Sprintf("UPPER(LTRIM(RTRIM(%s)))", column)

	exact := BuildINClause(normalizedCol, codes)
	prefixCodes := first3Codes(codes)
	if len(prefixCodes) == 0 {
		return exact
	}

	prefix := BuildINClause(
		fmt.Sprintf("LEFT(%s, 3)", normalizedCol),
		prefixCodes,
	)

	return fmt.Sprintf("(%s OR %s)", exact, prefix)
}

func first3Codes(codes []string) []string {
	seen := make(map[string]struct{}, len(codes))
	out := make([]string, 0, len(codes))

	for _, c := range codes {
		n := strings.ToUpper(strings.TrimSpace(c))
		if len(n) < 3 {
			continue
		}
		n = n[:3]
		if _, ok := seen[n]; ok {
			continue
		}
		seen[n] = struct{}{}
		out = append(out, n)
	}

	return out
}