Cyprus TIC

What it covers

Returns a valid Cyprus TIC (Tax Identification Code) — 8 digits plus a correct check letter. Use `format=vat` for the CY VAT number (`CY` + TIC). Set `invalid=true` for a TIC with a deliberately wrong check letter.

How it’s calculated

The Cyprus TIC appends one check letter A–Z equal to a position-dependent weighted digit sum taken modulo 26, where even-index digits are remapped through a fixed lookup table and odd-index digits count at face value.

Body digits by index: pos0=1, pos1=0, pos2=2, pos3=0, pos4=3, pos5=0, pos6=4, pos7=0.
Even positions (0,2,4,6) remapped through EVEN_DIGIT_MAP=[1,0,5,7,9,13,15,17,19,21]: pos0 digit 1 -> map[1]=0; pos2 digit 2 -> map[2]=5; pos4 digit 3 -> map[3]=7; pos6 digit 4 -> map[4]=9.
Odd positions (1,3,5,7) at face value: pos1=0, pos3=0, pos5=0, pos7=0.
Sum = (0 + 5 + 7 + 9) + (0 + 0 + 0 + 0) = 21.
21 mod 26 = 21.
Index 21 into 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' (A=0): letter is 'V'.

Edge cases

• The body's first digit is drawn 1–9, so a TIC never begins with 0; a leading-zero body is not issuable in this generator.
• The reserved body prefix '12' is never issued — bodies starting '12' are redrawn (isIssuableBody rejects them).

Gotchas

• The 'weight' is not a multiplier: even-index digits are transformed through a lookup table (EVEN_DIGIT_MAP), not multiplied by a weight, while odd-index digits pass through unchanged.
• The check character is a Latin letter A–Z from a mod-26 residue, not a digit; the alphabet is the plain 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' with A=0.
• The VAT number is exactly 'CY' + the national TIC (same 8 digits + same check letter); the 'CY' prefix does not participate in the checksum.