Files

136 lines
5.0 KiB
Go

package brain_control
import (
"crypto/sha256"
"encoding/hex"
"encoding/json"
"errors"
"fmt"
"regexp"
"strings"
"time"
)
var stableID = regexp.MustCompile(`^[A-Za-z0-9][A-Za-z0-9._~-]{0,127}$`)
func MapSourceConfig(f SourceFacts) (SourceConfig, error) {
if !stableID.MatchString(f.ConfigID) || !stableID.MatchString(f.SiteID) || !stableID.MatchString(f.LogicalDeviceID) || !stableID.MatchString(f.Profile.ID) || f.Revision < 1 || f.Profile.Width < 1 || f.Profile.Height < 1 || f.Profile.FrameRate <= 0 {
return SourceConfig{}, errors.New("invalid source configuration facts")
}
encoding := strings.ToUpper(f.Profile.Encoding)
if encoding != "H264" && encoding != "H265" && encoding != "MJPEG" {
return SourceConfig{}, errors.New("unsupported profile encoding")
}
if f.PublishedAt.IsZero() || f.EffectiveAt.Before(f.PublishedAt) {
return SourceConfig{}, errors.New("invalid source configuration time")
}
if !stableID.MatchString(f.RuleSetVersion) {
return SourceConfig{}, errors.New("invalid rule set version")
}
if strings.ContainsAny(f.MediaPath, "?#@\\") || strings.Contains(f.MediaPath, "://") || f.MediaPath == "" {
return SourceConfig{}, errors.New("media path must be opaque and credential-free")
}
if len(f.Areas) > 1024 || len(f.DirectionalLines) > 1024 {
return SourceConfig{}, errors.New("too many rules")
}
seen := map[string]bool{}
for _, a := range f.Areas {
if !stableID.MatchString(a.ID) || seen[a.ID] || a.Version < 1 || a.Kind != "danger_area" || len(a.Points) < 3 || len(a.Points) > 256 || !validPoints(a.Points) || polygonArea(a.Points) == 0 {
return SourceConfig{}, errors.New("invalid area rule")
}
seen[a.ID] = true
}
for _, l := range f.DirectionalLines {
if !stableID.MatchString(l.ID) || seen[l.ID] || l.Version < 1 || l.Kind != "directional_line" || (l.TriggerDirection != "left_to_right" && l.TriggerDirection != "right_to_left") || !validPoints([]Point{l.Start, l.End}) || l.Start == l.End {
return SourceConfig{}, errors.New("invalid directional line rule")
}
seen[l.ID] = true
}
var out SourceConfig
out.SchemaVersion, out.ConfigID, out.Revision = SourceConfigVersion, f.ConfigID, f.Revision
out.PublishedAt, out.EffectiveAt = f.PublishedAt.UTC(), f.EffectiveAt.UTC()
out.Site.ID, out.LogicalDevice.ID = f.SiteID, f.LogicalDeviceID
out.Profile = f.Profile
out.Profile.Encoding = encoding
out.Media.Ref, out.Media.Transport = "media:"+strings.TrimPrefix(f.MediaPath, "/"), "rtsp"
out.RuleSet.Version = f.RuleSetVersion
out.RuleSet.State = "active"
if f.Disabled {
out.RuleSet.State = "disabled"
}
if f.NeedsRecalibration {
out.RuleSet.State = "recalibration_required"
}
out.RuleSet.ProfileBinding.ProfileID, out.RuleSet.ProfileBinding.Width, out.RuleSet.ProfileBinding.Height = f.Profile.ID, f.Profile.Width, f.Profile.Height
out.RuleSet.Areas = append([]AreaRule(nil), f.Areas...)
out.RuleSet.DirectionalLines = append([]DirectionalLineRule(nil), f.DirectionalLines...)
if out.RuleSet.State != "active" {
for i := range out.RuleSet.Areas {
out.RuleSet.Areas[i].Enabled = false
}
for i := range out.RuleSet.DirectionalLines {
out.RuleSet.DirectionalLines[i].Enabled = false
}
}
digest, err := sourceDigest(out)
if err != nil {
return SourceConfig{}, err
}
out.Integrity.Algorithm, out.Integrity.Value = "sha256", digest
return out, nil
}
func MarshalSourceConfig(config SourceConfig) ([]byte, error) { return json.Marshal(config) }
func sourceDigest(config SourceConfig) (string, error) {
raw, err := json.Marshal(config)
if err != nil {
return "", err
}
var value map[string]any
if err = json.Unmarshal(raw, &value); err != nil {
return "", err
}
delete(value, "integrity")
canonical, err := json.Marshal(value)
if err != nil {
return "", err
}
sum := sha256.Sum256(canonical)
return hex.EncodeToString(sum[:]), nil
}
func validPoints(points []Point) bool {
for _, p := range points {
if p.X < 0 || p.X > 1 || p.Y < 0 || p.Y > 1 {
return false
}
}
return true
}
func polygonArea(p []Point) float64 {
var a float64
for i := range p {
n := p[(i+1)%len(p)]
a += p[i].X*n.Y - n.X*p[i].Y
}
if a < 0 {
a = -a
}
return a / 2
}
func ValidateSourceConfig(config SourceConfig) error {
if config.SchemaVersion != SourceConfigVersion {
return fmt.Errorf("unsupported source config version")
}
digest, err := sourceDigest(config)
if err != nil || config.Integrity.Algorithm != "sha256" || digest != config.Integrity.Value {
return errors.New("source config integrity mismatch")
}
_, err = MapSourceConfig(SourceFacts{ConfigID: config.ConfigID, SiteID: config.Site.ID, LogicalDeviceID: config.LogicalDevice.ID, MediaPath: strings.TrimPrefix(config.Media.Ref, "media:"), Revision: config.Revision, PublishedAt: config.PublishedAt, EffectiveAt: config.EffectiveAt, Profile: config.Profile, RuleSetVersion: config.RuleSet.Version, Disabled: config.RuleSet.State == "disabled", NeedsRecalibration: config.RuleSet.State == "recalibration_required", Areas: config.RuleSet.Areas, DirectionalLines: config.RuleSet.DirectionalLines})
return err
}
func UTCNow() time.Time { return time.Now().UTC() }