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.
}

// Frequency Allocation Table (Phase 9 design — major-second ladder, 65-2449 Hz)
//
// Slot  Hz    Class       Group            Waveform   Pan
// 0     65    ICMP        Infrastructure   Triangle   -0.3
// 1     73    NTP         Infrastructure   Triangle   -0.1
// 2     82    DHCP        Infrastructure   Triangle    0.1
// 3     93    mDNS        Infrastructure   Triangle    0.3    (Phase 10)
// 4     105   SSDP        Infrastructure   Triangle   -0.2    (Phase 10)
// 5     118   SNMP        Infrastructure   Triangle    0.2    (Phase 10)
// 6     133   DNS         Infrastructure   Triangle    0.0
// 7     150   HTTPS       Web              Sawtooth   -0.4
// 8     169   HTTP        Web              Sawtooth   -0.3
// 9     190   HTTP3       Web              Sawtooth   -0.2    (Phase 10)
// 10    214   SMTP        Mail             Triangle    0.2
// 11    241   IMAP        Mail             Triangle    0.3    (Phase 10)
// 12    271   POP3        Mail             Triangle    0.4    (Phase 10)
// 13    305   SMTP-sub    Mail             Triangle    0.5    (Phase 10)
// 14    343   SSH         Remote Access    Square     -0.7
// 15    385   RDP         Remote Access    Square     -0.6    (Phase 10)
// 16    432   Telnet      Remote Access    Square     -0.5    (Phase 10)
// 17    485   VNC         Remote Access    Square     -0.4    (Phase 10)
// 18    545   FTP         File Transfer    Square      0.5    (Phase 10)
// 19    612   SMB         File Transfer    Square      0.6    (Phase 10)
// 20    687   TFTP        File Transfer    Square      0.7    (Phase 10)
// 21    771   unknown-1   Unknown          Custom     -0.9
// 22    866   unknown-2   Unknown          Custom      0.9
// 23    972   unknown-3   Unknown          Custom     -0.7
// 24    1091  unknown-4   Unknown          Custom      0.7
// 25    1225  other-TCP   Unknown          Custom     -0.5
// 26    1375  other-UDP   Unknown          Custom      0.5
// 27    1543  MySQL       Database         Sawtooth   -0.4    (Phase 10)
// 28    1732  PostgreSQL  Database         Sawtooth   -0.2    (Phase 10)
// 29    1944  Redis       Database         Sawtooth    0.2    (Phase 10)
// 30    2182  MongoDB     Database         Sawtooth    0.4    (Phase 10)
// 31    2449  SIP         VoIP             Sine        0.0    (Phase 10)
//
// Auto-assign range: [2500, 4000] Hz (see config/config.go)

// ClassFreqConfigs maps each traffic class to its synthesis parameters.
// Frequencies per Phase 9 major-second ladder design. Harmonics per D-05/D-06.
// Pan positions per D-12. Group field drives family-aware config output (GRP-04).
var ClassFreqConfigs = map[classify.TrafficClass]FreqConfig{
	// --- Infrastructure (Triangle, 65-133 Hz) ---
	classify.ClassICMP: {
		BaseHz:       65.0,
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 65.0, SampleRate),
		Pan:          -0.3,
		Group:        "Infrastructure",
	},
	classify.ClassNTP: {
		BaseHz:       73.0,
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 73.0, SampleRate),
		Pan:          -0.1,
		Group:        "Infrastructure",
	},
	classify.ClassDHCP: {
		BaseHz:       82.0,
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 82.0, SampleRate),
		Pan:          0.1,
		Group:        "Infrastructure",
	},
	classify.ClassDNS: {
		BaseHz:       133.0,
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 133.0, SampleRate),
		Pan:          0.0,
		Group:        "Infrastructure",
	},
	// --- Web (Sawtooth, 150-169 Hz) ---
	classify.ClassHTTPS: {
		BaseHz:       150.0,
		WaveformType: WaveformSawtooth,
		Harmonics:    WaveformPresetHarmonics(WaveformSawtooth, 150.0, SampleRate),
		Pan:          -0.4,
		Group:        "Web",
	},
	classify.ClassHTTP: {
		BaseHz:       169.0,
		WaveformType: WaveformSawtooth,
		Harmonics:    WaveformPresetHarmonics(WaveformSawtooth, 169.0, SampleRate),
		Pan:          -0.3,
		Group:        "Web",
	},
	// --- Mail (Triangle, 214 Hz) ---
	classify.ClassSMTP: {
		BaseHz:       214.0,
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 214.0, SampleRate),
		Pan:          0.2,
		Group:        "Mail",
	},
		// --- Infrastructure additions (Triangle, 93-118 Hz) ---
	classify.ClassMDNS: {
		BaseHz:       93.0,
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 93.0, SampleRate),
		Pan:          0.3,
		Group:        "Infrastructure",
	},
	classify.ClassSSDP: {
		BaseHz:       105.0,
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 105.0, SampleRate),
		Pan:          -0.2,
		Group:        "Infrastructure",
	},
	classify.ClassSNMP: {
		BaseHz:       118.0,
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 118.0, SampleRate),
		Pan:          0.2,
		Group:        "Infrastructure",
	},
	// --- Web addition (Sawtooth, 190 Hz) ---
	classify.ClassQUIC: {
		BaseHz:       190.0,
		WaveformType: WaveformSawtooth,
		Harmonics:    WaveformPresetHarmonics(WaveformSawtooth, 190.0, SampleRate),
		Pan:          -0.2,
		Group:        "Web",
	},
	// --- Mail additions (Triangle, 241-305 Hz) ---
	classify.ClassIMAP: {
		BaseHz:       241.0,
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 241.0, SampleRate),
		Pan:          0.3,
		Group:        "Mail",
	},
	classify.ClassPOP3: {
		BaseHz:       271.0,
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 271.0, SampleRate),
		Pan:          0.4,
		Group:        "Mail",
	},
	classify.ClassSMTPSub: {
		BaseHz:       305.0,
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 305.0, SampleRate),
		Pan:          0.5,
		Group:        "Mail",
	},
	// --- Remote Access (Square, 343 Hz) ---
	classify.ClassSSH: {
		BaseHz:       343.0,
		WaveformType: WaveformSquare,
		Harmonics:    WaveformPresetHarmonics(WaveformSquare, 343.0, SampleRate),
		Pan:          -0.7,
		Group:        "Remote Access",
	},
	// --- Remote Access additions (Square, 385-485 Hz) ---
	classify.ClassRDP: {
		BaseHz:       385.0,
		WaveformType: WaveformSquare,
		Harmonics:    WaveformPresetHarmonics(WaveformSquare, 385.0, SampleRate),
		Pan:          -0.6,
		Group:        "Remote Access",
	},
	classify.ClassTelnet: {
		BaseHz:       432.0,
		WaveformType: WaveformSquare,
		Harmonics:    WaveformPresetHarmonics(WaveformSquare, 432.0, SampleRate),
		Pan:          -0.5,
		Group:        "Remote Access",
	},
	classify.ClassVNC: {
		BaseHz:       485.0,
		WaveformType: WaveformSquare,
		Harmonics:    WaveformPresetHarmonics(WaveformSquare, 485.0, SampleRate),
		Pan:          -0.4,
		Group:        "Remote Access",
	},
	// --- File Transfer additions (Square, 545-687 Hz) ---
	classify.ClassFTP: {
		BaseHz:       545.0,
		WaveformType: WaveformSquare,
		Harmonics:    WaveformPresetHarmonics(WaveformSquare, 545.0, SampleRate),
		Pan:          0.5,
		Group:        "File Transfer",
	},
	classify.ClassSMB: {
		BaseHz:       612.0,
		WaveformType: WaveformSquare,
		Harmonics:    WaveformPresetHarmonics(WaveformSquare, 612.0, SampleRate),
		Pan:          0.6,
		Group:        "File Transfer",
	},
	classify.ClassTFTP: {
		BaseHz:       687.0,
		WaveformType: WaveformSquare,
		Harmonics:    WaveformPresetHarmonics(WaveformSquare, 687.0, SampleRate),
		Pan:          0.7,
		Group:        "File Transfer",
	},
	// --- Unknown (Custom harmonics, 771-1375 Hz) ---
	// D-05/D-06: dissonant harmonic character {1,1.0},{2,0.8},{3,0.4} retained for all Unknown entries.
	// WaveformType is zero value (WaveformCustom) so bank.go uses the stored Harmonics directly.
	classify.ClassUnknown1: {
		BaseHz:    771.0,
		Harmonics: []HarmonicDef{{1, 1.0}, {2, 0.8}, {3, 0.4}},
		Pan:       -0.9,
		Group:     "Unknown",
	},
	classify.ClassUnknown2: {
		BaseHz:    866.0,
		Harmonics: []HarmonicDef{{1, 1.0}, {2, 0.8}, {3, 0.4}},
		Pan:       0.9,
		Group:     "Unknown",
	},
	classify.ClassUnknown3: {
		BaseHz:    972.0,
		Harmonics: []HarmonicDef{{1, 1.0}, {2, 0.8}, {3, 0.4}},
		Pan:       -0.7,
		Group:     "Unknown",
	},
	classify.ClassUnknown4: {
		BaseHz:    1091.0,
		Harmonics: []HarmonicDef{{1, 1.0}, {2, 0.8}, {3, 0.4}},
		Pan:       0.7,
		Group:     "Unknown",
	},
	classify.ClassOtherTCP: {
		BaseHz:    1225.0,
		Harmonics: []HarmonicDef{{1, 1.0}, {2, 0.8}, {3, 0.4}},
		Pan:       -0.5,
		Group:     "Unknown",
	},
	classify.ClassOtherUDP: {
		BaseHz:    1375.0,
		Harmonics: []HarmonicDef{{1, 1.0}, {2, 0.8}, {3, 0.4}},
		Pan:       0.5,
		Group:     "Unknown",
	},
	// --- Database additions (Sawtooth, 1543-2182 Hz) ---
	classify.ClassMySQL: {
		BaseHz:       1543.0,
		WaveformType: WaveformSawtooth,
		Harmonics:    WaveformPresetHarmonics(WaveformSawtooth, 1543.0, SampleRate),
		Pan:          -0.4,
		Group:        "Database",
	},
	classify.ClassPostgreSQL: {
		BaseHz:       1732.0,
		WaveformType: WaveformSawtooth,
		Harmonics:    WaveformPresetHarmonics(WaveformSawtooth, 1732.0, SampleRate),
		Pan:          -0.2,
		Group:        "Database",
	},
	classify.ClassRedis: {
		BaseHz:       1944.0,
		WaveformType: WaveformSawtooth,
		Harmonics:    WaveformPresetHarmonics(WaveformSawtooth, 1944.0, SampleRate),
		Pan:          0.2,
		Group:        "Database",
	},
	classify.ClassMongoDB: {
		BaseHz:       2182.0,
		WaveformType: WaveformSawtooth,
		Harmonics:    WaveformPresetHarmonics(WaveformSawtooth, 2182.0, SampleRate),
		Pan:          0.4,
		Group:        "Database",
	},
	// --- VoIP (Sine, 2449 Hz) ---
	classify.ClassSIP: {
		BaseHz:       2449.0,
		WaveformType: WaveformSine,
		Harmonics:    WaveformPresetHarmonics(WaveformSine, 2449.0, SampleRate),
		Pan:          0.0,
		Group:        "VoIP",
	},
	// --- Infrastructure auto-assigned (Triangle, 2950-3250 Hz) per D-02 ---
	classify.ClassLDAP: {
		BaseHz:       2950.0,
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 2950.0, SampleRate),
		Pan:          -0.2,
		Group:        "Infrastructure",
	},
	classify.ClassKerberos: {
		BaseHz:       3250.0,
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 3250.0, SampleRate),
		Pan:          0.0,
		Group:        "Infrastructure",
	},
	classify.ClassSyslog: {
		BaseHz:       3050.0,
		WaveformType: WaveformTriangle,
		Harmonics:    WaveformPresetHarmonics(WaveformTriangle, 3050.0, SampleRate),
		Pan:          0.2,
		Group:        "Infrastructure",
	},
}