Byte-snake-engine/team.go
2020-05-17 14:22:09 -07:00

128 lines
3.1 KiB
Go

package rules
import (
"errors"
)
type TeamRuleset struct {
StandardRuleset
TeamMap map[string]string
// These are intentionally designed so that they default to a standard game.
AllowBodyCollisions bool
SharedElimination bool
SharedHealth bool
SharedLength bool
}
const EliminatedByTeam = "team-eliminated"
func (r *TeamRuleset) CreateNextBoardState(prevState *BoardState, moves []SnakeMove) (*BoardState, error) {
nextBoardState, err := r.StandardRuleset.CreateNextBoardState(prevState, moves)
if err != nil {
return nil, err
}
// TODO: LOG?
err = r.resurrectTeamBodyCollisions(nextBoardState)
if err != nil {
return nil, err
}
// TODO: LOG?
err = r.shareTeamAttributes(nextBoardState)
if err != nil {
return nil, err
}
return nextBoardState, nil
}
func (r *TeamRuleset) areSnakesOnSameTeam(snake *Snake, other *Snake) bool {
return r.areSnakeIDsOnSameTeam(snake.ID, other.ID)
}
func (r *TeamRuleset) areSnakeIDsOnSameTeam(snakeID string, otherID string) bool {
return r.TeamMap[snakeID] == r.TeamMap[otherID]
}
func (r *TeamRuleset) resurrectTeamBodyCollisions(b *BoardState) error {
if !r.AllowBodyCollisions {
return nil
}
for i := 0; i < len(b.Snakes); i++ {
snake := &b.Snakes[i]
if snake.EliminatedCause == EliminatedByCollision {
if snake.EliminatedBy == "" {
return errors.New("snake eliminated by collision and eliminatedby is not set")
}
if snake.ID != snake.EliminatedBy && r.areSnakeIDsOnSameTeam(snake.ID, snake.EliminatedBy) {
snake.EliminatedCause = NotEliminated
snake.EliminatedBy = ""
}
}
}
return nil
}
func (r *TeamRuleset) shareTeamAttributes(b *BoardState) error {
if !(r.SharedElimination || r.SharedLength || r.SharedHealth) {
return nil
}
for i := 0; i < len(b.Snakes); i++ {
snake := &b.Snakes[i]
if snake.EliminatedCause != NotEliminated {
continue
}
for j := 0; j < len(b.Snakes); j++ {
other := &b.Snakes[j]
if r.areSnakesOnSameTeam(snake, other) {
if r.SharedHealth {
if snake.Health < other.Health {
snake.Health = other.Health
}
}
if r.SharedLength {
if len(snake.Body) == 0 || len(other.Body) == 0 {
return errors.New("found snake of zero length")
}
for len(snake.Body) < len(other.Body) {
r.growSnake(snake)
}
}
if r.SharedElimination {
if snake.EliminatedCause == NotEliminated && other.EliminatedCause != NotEliminated {
snake.EliminatedCause = EliminatedByTeam
// We intentionally do not set snake.EliminatedBy because there might be multiple culprits.
snake.EliminatedBy = ""
}
}
}
}
}
return nil
}
func (r *TeamRuleset) IsGameOver(b *BoardState) (bool, error) {
snakesRemaining := []*Snake{}
for i := 0; i < len(b.Snakes); i++ {
if b.Snakes[i].EliminatedCause == NotEliminated {
snakesRemaining = append(snakesRemaining, &b.Snakes[i])
}
}
for i := 0; i < len(snakesRemaining); i++ {
if !r.areSnakesOnSameTeam(snakesRemaining[i], snakesRemaining[0]) {
// There are multiple teams remaining
return false, nil
}
}
// no snakes or single team remaining
return true, nil
}