package synth

import "github.com/netsynth/netsynth/classify"

const (
	SampleRate       = 44100                        // D-13: CD quality
	WindowMs         = 500                          // matches aggregate.DefaultWindowMs
	SamplesPerWindow = SampleRate * WindowMs / 1000 // 22050
	WhisperFloor     = 0.03                         // D-08/D-09: 3% of max amplitude
)

// WaveformType selects the harmonic preset for a synthesis layer.
// The zero value WaveformCustom preserves existing hand-tuned harmonics in FreqConfig.Harmonics.
type WaveformType int

const (
	WaveformCustom   WaveformType = iota // zero value: use FreqConfig.Harmonics as-is
	WaveformSine                         // pure fundamental, single harmonic
	WaveformSquare                       // odd harmonics with 1/k amplitude (bandlimited)
	WaveformSawtooth                     // all harmonics with 1/k amplitude (bandlimited)
	WaveformTriangle                     // odd harmonics with alternating 1/k^2 amplitude (bandlimited)
)

// WaveformPresetHarmonics returns the bandlimited harmonic series for the given waveform type
// at the given base frequency and sample rate. Returns nil for WaveformCustom.
// All returned harmonics are below Nyquist (sampleRate/2).
func WaveformPresetHarmonics(wt WaveformType, baseHz float64, sampleRate int) []HarmonicDef {
	nyquist := float64(sampleRate) / 2.0
	switch wt {
	case WaveformCustom:
		return nil
	case WaveformSine:
		return []HarmonicDef{{Ratio: 1, Amplitude: 1.0}}
	case WaveformSquare:
		var harmonics []HarmonicDef
		for k := 1; float64(k)*baseHz < nyquist; k += 2 {
			harmonics = append(harmonics, HarmonicDef{Ratio: k, Amplitude: 1.0 / float64(k)})
		}
		return harmonics
	case WaveformSawtooth:
		var harmonics []HarmonicDef
		for k := 1; float64(k)*baseHz < nyquist; k++ {
			harmonics = append(harmonics, HarmonicDef{Ratio: k, Amplitude: 1.0 / float64(k)})
		}
		return harmonics
	case WaveformTriangle:
		var harmonics []HarmonicDef
		sign := 1.0
		for k := 1; float64(k)*baseHz < nyquist; k += 2 {
			harmonics = append(harmonics, HarmonicDef{Ratio: k, Amplitude: sign / float64(k*k)})
			sign = -sign
		}
		return harmonics
	default:
		return nil
	}
}

// HarmonicDef defines one partial in an additive synthesizer.
type HarmonicDef struct {
	Ratio     int     // harmonic number: 1=fundamental, 2=octave, 3=fifth+octave, etc.
	Amplitude float64 // relative weight
}

// FreqConfig holds synthesis parameters for one traffic class.
type FreqConfig struct {
	BaseHz       float64
	Harmonics    []HarmonicDef
	Pan          float64      // [-1, 1]: -1=full left, 0=center, +1=full right
	WaveformType WaveformType // zero value WaveformCustom uses Harmonics as-is
	Group        string       // sound family: "Infrastructure", "Web", "Mail", "Remote Access", "Unknown", etc.
	Bursty       bool         // true for event-like protocols (DNS, ICMP, NTP) — fast attack, no sustain
}

// Frequency Allocation Table — C Major Pentatonic, Just Intonation
//
// Scale: C D E G A across octaves 2-7 (ratios 1/1, 9/8, 5/4, 3/2, 5/3)
// Any combination of active tones is consonant — no dissonant intervals possible.
//
// Slot  Note  Hz      Class       Group            Waveform   Pan    Bursty
// 0     C2    65.4    ICMP        Infrastructure   Triangle   -0.3   yes
// 1     D2    73.6    NTP         Infrastructure   Triangle   -0.1   yes
// 2     E2    81.8    DHCP        Infrastructure   Triangle    0.1   yes
// 3     G2    98.0    mDNS        Infrastructure   Triangle    0.3   yes
// 4     A2    109.0   SSDP        Infrastructure   Triangle   -0.2   yes
// 5     C3    130.8   SNMP        Infrastructure   Triangle    0.2   yes
// 6     D3    146.8   DNS         Infrastructure   Triangle    0.0   yes
// 7     E3    163.5   HTTPS       Web              Sawtooth   -0.4   no
// 8     G3    196.0   HTTP        Web              Sawtooth   -0.3   no
// 9     A3    218.0   QUIC        Web              Sawtooth   -0.2   no
// 10    C4    261.6   SMTP        Mail             Triangle    0.2   no
// 11    D4    293.7   IMAP        Mail             Triangle    0.3   no
// 12    E4    327.0   POP3        Mail             Triangle    0.4   no
// 13    G4    392.0   SMTP-sub    Mail             Triangle    0.5   no
// 14    A4    436.0   SSH         Remote Access    Square     -0.7   no
// 15    C5    523.3   RDP         Remote Access    Square     -0.6   no
// 16    D5    587.3   Telnet      Remote Access    Square     -0.5   no
// 17    E5    654.1   VNC         Remote Access    Square     -0.4   no
// 18    G5    784.0   FTP         File Transfer    Square      0.5   no
// 19    A5    872.1   SMB         File Transfer    Square      0.6   no
// 20    C6    1046.5  TFTP        File Transfer    Square      0.7   no
// 21    D6    1174.7  unknown-1   Unknown          Custom     -0.9   no
// 22    E6    1308.1  unknown-2   Unknown          Custom      0.9   no
// 23    G6    1568.0  unknown-3   Unknown          Custom     -0.7   no
// 24    A6    1744.2  unknown-4   Unknown          Custom      0.7   no
// 25    C7    2093.0  other-TCP   Unknown          Custom     -0.5   no
// 26    D7    2349.3  other-UDP   Unknown          Custom      0.5   no
// 27    E7    2616.1  MySQL       Database         Sawtooth   -0.4   no
// 28    G7    3136.0  PostgreSQL  Database         Sawtooth   -0.2   no
// 29    A7    3488.4  Redis       Database         Sawtooth    0.2   no
// 30    C8    4186.0  MongoDB     Database         Sawtooth    0.4   no
// 31    D8    4704.0  SIP         VoIP             Sine        0.0   no
//
// Auto-assign range: [5000, 8000] Hz (see config/config.go)
// LDAP, Kerberos, Syslog: assigned to pentatonic slots in octave 3 (infrastructure)

// ClassFreqConfigs maps each traffic class to its synthesis parameters.
// Frequencies: C Major Pentatonic (just intonation) across octaves 2-8.
// Pan positions per D-12. Group field drives family-aware config output (GRP-04).
var ClassFreqConfigs = map[classify.TrafficClass]FreqConfig{
	// --- Infrastructure (Triangle, C2-D3, bursty) ---
	classify.ClassICMP: {
		BaseHz:       65.4, // C2
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 65.4, SampleRate),
		Pan:          -0.3,
		Group:        "Infrastructure",
		Bursty:       true,
	},
	classify.ClassNTP: {
		BaseHz:       73.6, // D2
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 73.6, SampleRate),
		Pan:          -0.1,
		Group:        "Infrastructure",
		Bursty:       true,
	},
	classify.ClassDHCP: {
		BaseHz:       81.8, // E2
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 81.8, SampleRate),
		Pan:          0.1,
		Group:        "Infrastructure",
		Bursty:       true,
	},
	classify.ClassMDNS: {
		BaseHz:       98.0, // G2
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 98.0, SampleRate),
		Pan:          0.3,
		Group:        "Infrastructure",
		Bursty:       true,
	},
	classify.ClassSSDP: {
		BaseHz:       109.0, // A2
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 109.0, SampleRate),
		Pan:          -0.2,
		Group:        "Infrastructure",
		Bursty:       true,
	},
	classify.ClassSNMP: {
		BaseHz:       130.8, // C3
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 130.8, SampleRate),
		Pan:          0.2,
		Group:        "Infrastructure",
		Bursty:       true,
	},
	classify.ClassDNS: {
		BaseHz:       146.8, // D3
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 146.8, SampleRate),
		Pan:          0.0,
		Group:        "Infrastructure",
		Bursty:       true,
	},
	// --- Web (Sawtooth, E3-A3, sustained) ---
	classify.ClassHTTPS: {
		BaseHz:       163.5, // E3
		WaveformType: WaveformSawtooth,
		Harmonics:    WaveformPresetHarmonics(WaveformSawtooth, 163.5, SampleRate),
		Pan:          -0.4,
		Group:        "Web",
	},
	classify.ClassHTTP: {
		BaseHz:       196.0, // G3
		WaveformType: WaveformSawtooth,
		Harmonics:    WaveformPresetHarmonics(WaveformSawtooth, 196.0, SampleRate),
		Pan:          -0.3,
		Group:        "Web",
	},
	classify.ClassQUIC: {
		BaseHz:       218.0, // A3
		WaveformType: WaveformSawtooth,
		Harmonics:    WaveformPresetHarmonics(WaveformSawtooth, 218.0, SampleRate),
		Pan:          -0.2,
		Group:        "Web",
	},
	// --- Mail (Triangle, C4-G4) ---
	classify.ClassSMTP: {
		BaseHz:       261.6, // C4
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 261.6, SampleRate),
		Pan:          0.2,
		Group:        "Mail",
	},
	classify.ClassIMAP: {
		BaseHz:       293.7, // D4
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 293.7, SampleRate),
		Pan:          0.3,
		Group:        "Mail",
	},
	classify.ClassPOP3: {
		BaseHz:       327.0, // E4
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 327.0, SampleRate),
		Pan:          0.4,
		Group:        "Mail",
	},
	classify.ClassSMTPSub: {
		BaseHz:       392.0, // G4
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 392.0, SampleRate),
		Pan:          0.5,
		Group:        "Mail",
	},
	// --- Remote Access (Square, A4-E5) ---
	classify.ClassSSH: {
		BaseHz:       436.0, // A4
		WaveformType: WaveformSquare,
		Harmonics:    WaveformPresetHarmonics(WaveformSquare, 436.0, SampleRate),
		Pan:          -0.7,
		Group:        "Remote Access",
	},
	classify.ClassRDP: {
		BaseHz:       523.3, // C5
		WaveformType: WaveformSquare,
		Harmonics:    WaveformPresetHarmonics(WaveformSquare, 523.3, SampleRate),
		Pan:          -0.6,
		Group:        "Remote Access",
	},
	classify.ClassTelnet: {
		BaseHz:       587.3, // D5
		WaveformType: WaveformSquare,
		Harmonics:    WaveformPresetHarmonics(WaveformSquare, 587.3, SampleRate),
		Pan:          -0.5,
		Group:        "Remote Access",
	},
	classify.ClassVNC: {
		BaseHz:       654.1, // E5
		WaveformType: WaveformSquare,
		Harmonics:    WaveformPresetHarmonics(WaveformSquare, 654.1, SampleRate),
		Pan:          -0.4,
		Group:        "Remote Access",
	},
	// --- File Transfer (Square, G5-C6) ---
	classify.ClassFTP: {
		BaseHz:       784.0, // G5
		WaveformType: WaveformSquare,
		Harmonics:    WaveformPresetHarmonics(WaveformSquare, 784.0, SampleRate),
		Pan:          0.5,
		Group:        "File Transfer",
	},
	classify.ClassSMB: {
		BaseHz:       872.1, // A5
		WaveformType: WaveformSquare,
		Harmonics:    WaveformPresetHarmonics(WaveformSquare, 872.1, SampleRate),
		Pan:          0.6,
		Group:        "File Transfer",
	},
	classify.ClassTFTP: {
		BaseHz:       1046.5, // C6
		WaveformType: WaveformSquare,
		Harmonics:    WaveformPresetHarmonics(WaveformSquare, 1046.5, SampleRate),
		Pan:          0.7,
		Group:        "File Transfer",
	},
	// --- Unknown (Custom harmonics, D6-D7) ---
	// Dissonant harmonic character {1,1.0},{2,0.8},{3,0.4} retained for all Unknown entries.
	classify.ClassUnknown1: {
		BaseHz:    1174.7, // D6
		Harmonics: []HarmonicDef{{1, 1.0}, {2, 0.8}, {3, 0.4}},
		Pan:       -0.9,
		Group:     "Unknown",
	},
	classify.ClassUnknown2: {
		BaseHz:    1308.1, // E6
		Harmonics: []HarmonicDef{{1, 1.0}, {2, 0.8}, {3, 0.4}},
		Pan:       0.9,
		Group:     "Unknown",
	},
	classify.ClassUnknown3: {
		BaseHz:    1568.0, // G6
		Harmonics: []HarmonicDef{{1, 1.0}, {2, 0.8}, {3, 0.4}},
		Pan:       -0.7,
		Group:     "Unknown",
	},
	classify.ClassUnknown4: {
		BaseHz:    1744.2, // A6
		Harmonics: []HarmonicDef{{1, 1.0}, {2, 0.8}, {3, 0.4}},
		Pan:       0.7,
		Group:     "Unknown",
	},
	classify.ClassOtherTCP: {
		BaseHz:    2093.0, // C7
		Harmonics: []HarmonicDef{{1, 1.0}, {2, 0.8}, {3, 0.4}},
		Pan:       -0.5,
		Group:     "Unknown",
	},
	classify.ClassOtherUDP: {
		BaseHz:    2349.3, // D7
		Harmonics: []HarmonicDef{{1, 1.0}, {2, 0.8}, {3, 0.4}},
		Pan:       0.5,
		Group:     "Unknown",
	},
	// --- Database (Sawtooth, E7-C8) ---
	classify.ClassMySQL: {
		BaseHz:       2616.1, // E7
		WaveformType: WaveformSawtooth,
		Harmonics:    WaveformPresetHarmonics(WaveformSawtooth, 2616.1, SampleRate),
		Pan:          -0.4,
		Group:        "Database",
	},
	classify.ClassPostgreSQL: {
		BaseHz:       3136.0, // G7
		WaveformType: WaveformSawtooth,
		Harmonics:    WaveformPresetHarmonics(WaveformSawtooth, 3136.0, SampleRate),
		Pan:          -0.2,
		Group:        "Database",
	},
	classify.ClassRedis: {
		BaseHz:       3488.4, // A7
		WaveformType: WaveformSawtooth,
		Harmonics:    WaveformPresetHarmonics(WaveformSawtooth, 3488.4, SampleRate),
		Pan:          0.2,
		Group:        "Database",
	},
	classify.ClassMongoDB: {
		BaseHz:       4186.0, // C8
		WaveformType: WaveformSawtooth,
		Harmonics:    WaveformPresetHarmonics(WaveformSawtooth, 4186.0, SampleRate),
		Pan:          0.4,
		Group:        "Database",
	},
	// --- VoIP (Sine, D8) ---
	classify.ClassSIP: {
		BaseHz:       4704.0, // D8
		WaveformType: WaveformSine,
		Harmonics:    WaveformPresetHarmonics(WaveformSine, 4704.0, SampleRate),
		Pan:          0.0,
		Group:        "VoIP",
	},
	// --- Infrastructure auto-assigned (Triangle, pentatonic upper octaves) ---
	classify.ClassLDAP: {
		BaseHz:       5232.0, // E8 — auto-assign range
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 5232.0, SampleRate),
		Pan:          -0.2,
		Group:        "Infrastructure",
		Bursty:       true,
	},
	classify.ClassKerberos: {
		BaseHz:       5878.0, // G8 (approx) — auto-assign range
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 5878.0, SampleRate),
		Pan:          0.0,
		Group:        "Infrastructure",
		Bursty:       true,
	},
	classify.ClassSyslog: {
		BaseHz:       6534.0, // A8 (approx) — auto-assign range
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 6534.0, SampleRate),
		Pan:          0.2,
		Group:        "Infrastructure",
		Bursty:       true,
	},
}