I just have run vg giraffe to align short reads against pan-genome graph and produced a gaf file. what is the meaning of "cs","dv", "fp" and "pd" tag in each line.?

In addition, is there any tool that can calculate summary statistics of GAF file. like samtools stats command.

the following is sample lines:

HISEQ1:18:H8VC6ADXX:1:1101:3522:2238    148     0       148     +       <83081273<83081271<83081269<83081268    243     16      164     148     148     60      AS:i:158        bq:Z:CCCFFFFFHHHHFHJJJJJIJJJJJHIJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJIJJJHHHHFFFFFEEEEEEEDDDDEEDEDDD?BDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDBDEEEEDCA       cs:Z::148       dv:f:0  fn:Z:HISEQ1:18:H8VC6ADXX:1:1101:3522:2238       pd:b:1
HISEQ1:18:H8VC6ADXX:1:1101:3522:2238    148     0       148     +       >83081250>83081251>83081253>83081254>83081256   233     3       151     148     148     60      AS:i:158        bq:Z:CCCFFDFFHHHHHJJJIIJJJJJJJJJJJIJJJJJIIIJJJJJJJJIJIJJJJHIJJJCGGHJJHIIIGJJJJJJJHHHGHHHFFFFFFFFEEDEEEEEDBACEDEDEEEDDDDDDDDDDEDDEDEEEEEDEDDDDDDCDEDEEDDD@       cs:Z::148       dv:f:0  fp:Z:HISEQ1:18:H8VC6ADXX:1:1101:3522:2238       pd:b:1
HISEQ1:18:H8VC6ADXX:1:1101:4056:2227    148     0       148     +       >16364644>16364645>16364647     390     60      208     148     148     60      AS:i:158        bq:Z:CC@FFFFFHHHHHJJJJJJJJJJJJJJJIIJJIIJJJJHIJJJJJJJJJJIIIGIIJHIGIGIIJJIIIJIJJHIIJEHHHHHHFFFFFFECDDDDDDDEDCCCDDDDDDDDDDEDDDDDACDDDDDDDDDDDDDDDDDDDDDDDED?       cs:Z::148       dv:f:0  fn:Z:HISEQ1:18:H8VC6ADXX:1:1101:4056:2227       pd:b:1
HISEQ1:18:H8VC6ADXX:1:1101:4056:2227    148     0       148     +       <16364647<16364645<16364644     390     58      206     148     148     60      AS:i:158        bq:Z:CCCFFFFFHHHHGJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJIJJJJJJJJJJJHIIIJIGJJJGGIJJIJJIHHHHHHHFFFFFEDEEEEDDDDDDACCDDDDDDDDDCDEDCEDDDDDEDEDDDBDDDDEEDDDDDDDDBDD       cs:Z::148       dv:f:0  fp:Z:HISEQ1:18:H8VC6ADXX:1:1101:4056:2227       pd:b:1
HISEQ1:18:H8VC6ADXX:1:1101:6143:2209    148     0       148     +       <76773276<76773275<76773273<76773272<76773270   591     174     322     148     148     60      AS:i:158        bq:Z:CCCFFFFFHHHHHJJJJJHIEHIJJJHHIIEHGGIIJJJIJJIJIJJJJIJJIGIIJHHFGHHFFFFFFEDEEEEDDCD?ACDDDDDDDDBDC@CDECDCC>CDDDDDCDDCDDCDEEDD9ACDDDDDDCDDDDDDDDDDDDDDDDDD       cs:Z::148       dv:f:0  fn:Z:HISEQ1:18:H8VC6ADXX:1:1101:6143:2209       pd:b:1
HISEQ1:18:H8VC6ADXX:1:1101:6143:2209    148     0       148     +       >76773270       301     42      190     134     148     60      AS:i:136        bq:Z:@BBFFFFFHHHGFHHIJJIJJJJJJJJJHIJJJJFHIIJJJJJJIIGJJIIJGJJGIJJJJJICFFF#-;DHIHHHHHHHFFFFFDEEEEDDDDDCDDA#,5<@BDDDDDDDDDDDDDDDDDDDDDDDD@###++8##+###+##+##       cs:Z::67*TN:31*TN:30*CN*CN*AN:3*TN*TN:1*TN*CN*TN:1*TN*TN:1*AN*TN        dv:f:0.0946     fp:Z:HISEQ1:18:H8VC6ADXX:1:1101:6143:2209       pd:b:1