params.gno

 1package penalty
 2
 3import (
 4	"errors"
 5	"strconv"
 6)
 7
 8const (
 9	BallRadius = 110   // mm
10	PostRadius = 60    // mm
11	Distance   = 11000 // penalty spot to goal line, mm
12	Gravity    = 9810  // mm/s²
13
14	AimMaxX = 6000 // the aim point must lie within ±6 m of the goal centre
15	AimMaxY = 4000 // and between the grass and 4 m up
16)
17
18// ShotInput is what a taker chooses: the five numbers a player sends.
19type ShotInput struct {
20	AimX     int64 // point on the goal plane the swing heads for, mm from the centre (+ = taker's right)
21	AimY     int64 // its height, mm
22	ContactX int64 // where the boot meets the ball, milli-radii from its centre (+ = right)
23	ContactY int64 // milli-radii (+ = above centre)
24	Power    int64 // per-mille
25}
26
27// ShotParams is a complete kick: the taker's five choices plus the 24-byte
28// mishit seed that decides how far the boot lands from the chosen contact.
29// These six, with a keeper's four, are the ten inputs of SimulateShot.
30type ShotParams struct {
31	AimX     int64
32	AimY     int64
33	ContactX int64
34	ContactY int64
35	Power    int64
36	Mishit   [24]byte
37}
38
39// KeeperPlan is the keeper's commitment: four uint16 values that DecodePlan
40// maps onto a dive using the game's Config.
41type KeeperPlan struct {
42	Direction uint16
43	Speed     uint16
44	Jump      uint16
45	Reaction  uint16
46}
47
48var ErrShotRange = errors.New("penalty: shot parameter out of range")
49
50// Validate checks a taker's choices against the game's constants.
51func (s ShotInput) Validate(c Config) error {
52	if s.AimX < -AimMaxX || s.AimX > AimMaxX {
53		return errors.New(ErrShotRange.Error() + ": aimX must be within ±" + strconv.Itoa(AimMaxX) + " mm")
54	}
55	if s.AimY < 0 || s.AimY > AimMaxY {
56		return errors.New(ErrShotRange.Error() + ": aimY must be within 0.." + strconv.Itoa(AimMaxY) + " mm")
57	}
58	if s.ContactX*s.ContactX+s.ContactY*s.ContactY > c.MaxContact*c.MaxContact {
59		return errors.New(ErrShotRange.Error() + ": contact offset must be within " +
60			strconv.FormatInt(c.MaxContact, 10) + " milli-radii of the centre")
61	}
62	if s.Power < 0 || s.Power > 1000 {
63		return errors.New(ErrShotRange.Error() + ": power must be within 0..1000")
64	}
65	return nil
66}
67
68// WithMishit completes a taker's choices with a mishit seed.
69func (s ShotInput) WithMishit(m [24]byte) ShotParams {
70	return ShotParams{AimX: s.AimX, AimY: s.AimY, ContactX: s.ContactX, ContactY: s.ContactY, Power: s.Power, Mishit: m}
71}
72
73// Input returns the taker's five choices.
74func (s ShotParams) Input() ShotInput {
75	return ShotInput{AimX: s.AimX, AimY: s.AimY, ContactX: s.ContactX, ContactY: s.ContactY, Power: s.Power}
76}
77
78func (s ShotInput) String() string {
79	return "aim=(" + strconv.FormatInt(s.AimX, 10) + "," + strconv.FormatInt(s.AimY, 10) + ")mm contact=(" +
80		strconv.FormatInt(s.ContactX, 10) + "," + strconv.FormatInt(s.ContactY, 10) + ")mR power=" +
81		strconv.FormatInt(s.Power, 10) + "‰"
82}
83
84func (p KeeperPlan) String() string {
85	return "plan=(" + strconv.Itoa(int(p.Direction)) + "," + strconv.Itoa(int(p.Speed)) + "," +
86		strconv.Itoa(int(p.Jump)) + "," + strconv.Itoa(int(p.Reaction)) + ")"
87}