#!/usr/bin/env python3
"""
Tronica - 90s Trance / EBM
Driving hypnotic 90s trance with arpeggiated leads, wide choir pads,
and propulsive rhythm. 138 BPM.

Structure: 40 bars
Intro  (4 bars) - sparse 16th-notes
Build  (8 bars) - speed to 32nd-notes
Drop   (8 bars) - full 32nd-notes
Break  (8 bars) - back to 16th-notes
Drop2  (8 bars) - full 32nd-notes
Outro  (4 bars) - fade out

Instruments:
  T0: Lead 1 Synth   GM 80 - driving arpeggio
  T1: Pad 4 Choir    GM 88 - sustained pads
  T2: Drum set       Ch 10 - trance dance beat
  T3: Lead 3 Synth   GM 84 - accent in drops
"""
from midiutil import MIDIFile

BPM = 138
PPQ = 960

CHORDS = [
    {"root": 48, "arp": (0, 3, 7, 12)},
    {"root": 45, "arp": (0, 4, 7, 12)},
    {"root": 50, "arp": (0, 4, 7, 12)},
    {"root": 46, "arp": (0, 2, 7, 12)},
]

total_bars = 40
fill_bars = {3, 11, 19, 27}

def sp(v):
    """Safe pitch: return only if 0-127."""
    return v if 0 <= v < 128 else None

# ========= Create MIDI File =========
midi = MIDIFile(4, file_format=1, ticks_per_quarternote=PPQ)
midi.addTempo(0, 0, BPM)
midi.addProgramChange(0, 0, 0, 80)
midi.addProgramChange(1, 0, 0, 88)
midi.addProgramChange(3, 9, 0, 84)

# ========= Track 0: Arpeggio =========
for start, num, spd in [(0,4,4), (4,8,8), (12,8,8), (20,8,4), (28,8,8)]:
    dt = 1.0 / spd
    for bar in range(start, start + num):
        chord = CHORDS[bar % 4]
        r = chord["root"]
        ints = chord["arp"]
        for i in range(4 * spd):
            p = sp(r + ints[i % 4] + (i // 4) * 12)
            if p is not None:
                v = 88 if i % 4 else 93
                midi.addNote(0, 0, p, bar * 4 + i * dt, dt * 0.85, v)

# Outro fade (4 bars, decrescendo)
for bar in range(36, 40):
    chord = CHORDS[bar % 4]
    for i in range(4):
        p = sp(chord["root"] + chord["arp"][i % 4])
        if p is not None:
            midi.addNote(0, 0, p, bar * 4 + i * 0.25, 0.2, max(35, 75 - (bar-36)*15))

# ========= Track 1: Pads =========
midi.addControllerEvent(1, 0, 0, 91, 75)   # Reverb
midi.addControllerEvent(1, 0, 0, 93, 85)   # Chorus
midi.addControllerEvent(1, 0, 0, 11, 127)  # Expression
for bar in range(total_bars):
    r = CHORDS[bar % 4]["root"]
    for n in [r+7, r+12, r+19]:
        midi.addNote(1, 0, n, bar*4, 3.9 if bar%2==0 else 3.7, 50)

# ========= Track 2: Drums =========
for bar in range(total_bars):
    base = bar * 4
    for beat in range(4):
        bt = base + beat
        midi.addNote(2, 9, 36, bt, 0.2, 115 if beat==0 else 105)
        if beat in (1, 3):
            midi.addNote(2, 9, 38, bt, 0.2, 110 if bar in fill_bars else 90)
        midi.addNote(2, 9, 42, bt + 0.5, 0.1, 70)
    if bar in fill_bars:
        midi.addNote(2, 9, 46, base + 3.5, 0.3, 80)
        midi.addNote(2, 9, 46, base + 3.75, 0.2, 75)

# ========= Track 3: Lead Cues =========
for bar in range(8):
    bt = (12 + bar) * 4
    r = CHORDS[(12 + bar) % 4]["root"]
    for bp, off in [(0,12),(0.5,16),(1.0,19),(2.0,16),(2.5,19),(3.0,24)]:
        midi.addNote(3, 9, r+off, bt+bp, 0.5, 90)
for bar in range(8):
    bt = (28 + bar) * 4
    r = CHORDS[(28 + bar) % 4]["root"]
    for bp, off in [(0,12),(0.5,16),(1.0,19),(2.0,16),(2.5,19),(3.0,24)]:
        midi.addNote(3, 9, r+off, bt+bp, 0.5, 90)

# Pitch bend
for bar in range(8):
    bt = (4 + bar) * 4
    midi.addPitchWheelEvent(0, 0, bt, 3000 + bar*500)
    midi.addPitchWheelEvent(0, 0, bt + 2, -(3000 + bar*500))

# ========= Write =========
output_file = "/home/paperclip/projects/gitea/pi-midi-zone/midi_output/tronica.mid"
with open(output_file, "wb") as f:
    midi.writeFile(f)

print(f"Written: {output_file}")
print(f"  4-track, {total_bars} bars at {BPM} BPM")
print(f"  Style: 90s Trance / EBM")