Function AirportFindFreeTerminal

src/aircraft_cmd.cpp:2007–2052

* Find a free terminal, and assign it if available. * @param v Aircraft to handle. * @param apc Airport state machine. * @return Found a free terminal and assigned it. */

 * @return Found a free terminal and assigned it.
 */
static bool AirportFindFreeTerminal(Aircraft *v, const AirportFTAClass *apc)
{
	/* example of more terminalgroups
	 * {0,HANGAR,AirportBlock::Nothing,1}, {0,TERMGROUP,AirportBlock::TermGroup1,0}, {0,TERMGROUP,TERM_GROUP2_ENTER_block,1}, {0,0,N,1},
	 * Heading TERMGROUP denotes a group. We see 2 groups here:
	 * 1. group 0 -- AirportBlock::TermGroup1 (check block)
	 * 2. group 1 -- TERM_GROUP2_ENTER_block (check block)
	 * First in line is checked first, group 0. If the block (AirportBlock::TermGroup1) is free, it
	 * looks at the corresponding terminals of that group. If no free ones are found, other
	 * possible groups are checked (in this case group 1, since that is after group 0). If that
	 * fails, then attempt fails and plane waits
	 */
	if (apc->terminals[0] > 1) {
		const Station *st = Station::Get(v->targetairport);
		const AirportFTA *temp = apc->layout[v->pos].next.get();

		while (temp != nullptr) {
			if (temp->heading == TERMGROUP) {
				if (!st->airport.blocks.Any(temp->blocks)) {
					/* read which group do we want to go to?
					 * (the first free group) */
					uint target_group = temp->next_position + 1;

					/* at what terminal does the group start?
					 * that means, sum up all terminals of
					 * groups with lower number */
					uint group_start = 0;
					for (uint i = 1; i < target_group; i++) {
						group_start += apc->terminals[i];
					}

					uint group_end = group_start + apc->terminals[target_group];
					if (FreeTerminal(v, group_start, group_end)) return true;
				}
			} else {
				/* once the heading isn't 255, we've exhausted the possible blocks.
				 * So we cannot move */
				return false;
			}
			temp = temp->next.get();
		}
	}

	/* if there is only 1 terminalgroup, all terminals are checked (starting from 0 to max) */
	return FreeTerminal(v, 0, GetNumTerminals(apc));
}

/**
 * Find a free helipad, and assign it if available.