File size: 1,282 Bytes
1e69593 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 | package productcode
import (
"fmt"
"mexa/api/v1/db"
)
const charset = "ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
func encodeBase60(n int64, length int) string {
base := int64(len(charset))
result := make([]byte, length)
for i := length - 1; i >= 0; i-- {
result[i] = charset[n%base]
n /= base
}
return string(result)
}
// Generate returns a 6-char product code: T1+T2+T3+S1+S2+S3.
// T1, T2, T3 are single chars from the 60-char charset.
// S1-S3 is a 3-char base-60 sequence — 216,000 per group.
// System-generated only. mrShymo never constructs or chooses a code.
// UPSERT ensures the group row is created on first use — no seeding required.
func Generate(t1, t2, t3 string) (string, error) {
if len(t1) != 1 || len(t2) != 1 || len(t3) != 1 {
return "", fmt.Errorf("t1, t2, t3 must each be exactly 1 char")
}
group := t1 + t2 + t3
var seq int64
err := db.DB.QueryRow(`
INSERT INTO product_sequences (group_key, current_val)
VALUES ($1, 1)
ON CONFLICT (group_key)
DO UPDATE SET current_val = product_sequences.current_val + 1
RETURNING current_val
`, group).Scan(&seq)
if err != nil {
return "", fmt.Errorf("product_sequences upsert failed for group %s: %w", group, err)
}
return group + encodeBase60(seq, 3), nil
}
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