Tell the number of chars in a string

• Handle the GSM Charset
• Handle the GSM extended charset (a character counts for two 7-bit chars)
• Handle the UCS-2 charset (all characters counts for 2 bytes)

A SMS is allowed for 140 bytes, multipart SMS needs a 7 bytes header to be linked to each other's.

Tell the number of chars per SMS with regards to the mandatory message encoding

• Handle the GSM Charset
• Handle the GSM extended charset (a character counts for two 7-bit chars)
• Handle the UCS-2 charset (all characters counts for 2 bytes)

A SMS is allowed for 140 bytes, multipart SMS needs a 7 bytes header to be linked to each other's.

Tell the number of SMS message mandatory with regards to the current message string and encoding