#!/usr/bin/env python3
"""
"Kestrel Over The Fens" — N64-era ambient exploration theme
Style: Ocarina-of-Time-adjacent. G major with Lydian sparkle, 72 BPM.
Structure: 4-bar intro, phrase 1 (8), phrase 2 higher (8), coda (4).

The N64 fingerprints:
  - pan flute lead, long breathy phrases, gentle vibrato
  - warm pad chords breathing underneath (whole notes, low velocity)
  - harp arpeggios instead of the DOS 16ths — everything floats
  - one C#6 in bar 13 (Lydian #11) that does the emotional heavy lifting
"""
import os, sys
sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", "lib"))
from midikit import MidiFile, Track, MPQN, verify, note as N
from songkit import bar, melody, arp, vibrato, TPQ

BPM = 72
OUT = os.path.join(os.path.dirname(__file__), "..", "midi",
                   "02_kestrel_over_the_fens.mid")

CHORDS = (
    [("G", "add9"), ("D", "7"), ("E", "m7"), ("C", "maj7")] +        # intro
    [("G", "add9"), ("D", "7"), ("E", "m7"), ("C", "maj7"),
     ("A", "m7"), ("D", "sus"), ("G", "add9"), ("C", "add9")] +      # P1
    [("C", "add9"), ("G", "add9"), ("E", "m7"), ("D", "sus"),
     ("C", "add9"), ("G", "add9"), ("A", "m7"), ("D", "sus")] +      # P2
    [("G", "add9"), ("C", "add9"), ("G", "add9"), ("G", "")]         # coda
)
# D7/F# feel via bass line; Dsus resolves the phrase.

PHRASE_1 = """
D5-4 G5-4 A5-2 | F#5-4 E5-4 D5-2 | E5-4 G5-4 F#5-2 | E5-4 D5-4 C5-2 |
A4-8 C5-8 E5-4 A5-2 | D5-4 E5-4 D5-2 | G5-1 | r4 B5-4 A5-4 G5-4
"""
PHRASE_2 = """
E5-4 G5-4 D5-4 E5-4 | B5-4 C#6-4 B5-2 | D6-4 B5-4 G5-4 E5-4 |
F#5-4 A5-4 G5-2 | E5-8 G5-8 A5-4 G5-4 E5-4 | D5-4 G5-4 B5-2 |
C6-4 B5-4 A5-4 E5-4 | D6-2 A5-4 F#5-4
"""
CODA = """
G5-1 | E5-2 D5-2 | D5-2 B4-2 | G5-1
"""


def build():
    mf = MidiFile(tpq=TPQ)
    mf.time_sig = (4, 2)
    mf.key_sig = (1, False)                  # G major
    mf.tempos = [MPQN.from_bpm(0, BPM)]

    lead = Track("Pan flute", channel=0)
    lead.program(0, "pan flute")
    lead.cc(0, 7, 92); lead.cc(0, 10, 58)
    pad = Track("Warm pad", channel=1)
    pad.program(0, "warm pad")
    pad.cc(0, 7, 58); pad.cc(0, 10, 40)
    harp = Track("Harp", channel=2)
    harp.program(0, "orchestral harp")
    harp.cc(0, 7, 72); harp.cc(0, 10, 84)
    bass = Track("Cello", channel=3)
    bass.program(0, "cello")
    bass.cc(0, 7, 80); bass.cc(0, 10, 34)

    def pad_chords(start, count):
        for i in range(count):
            root, qual = CHORDS[start + i]
            for iv in (0, 4 if qual not in ("m", "m7", "m7b5") else 3, 7):
                pad.note(bar(start + i), N(root + "3") + iv, TPQ * 4, 55)

    def bass_roots(start, count):
        for i in range(count):
            bass.note(bar(start + i), N(CHORDS[start + i][0] + "2"),
                      TPQ * 4, 70)

    # intro: harp + pad only
    arp(harp, 0, CHORDS[0:4], pattern="0121", subdivision=2,
        velocity=52, octave=4, duration=TPQ)
    pad_chords(0, 4); bass_roots(0, 4)

    # phrase 1
    melody(lead, 4, PHRASE_1)
    vibrato(lead, bar(4), bar(12), tempo_bpm=BPM, depth=0.4, rate=4.5)
    arp(harp, 4, CHORDS[4:12], pattern="0121", subdivision=2,
        velocity=56, octave=4, duration=TPQ)
    pad_chords(4, 8); bass_roots(4, 8)

    # phrase 2: harp moves up, pad swells
    melody(lead, 12, PHRASE_2)
    vibrato(lead, bar(12), bar(20), tempo_bpm=BPM, depth=0.45, rate=5.0)
    arp(harp, 12, CHORDS[12:20], pattern="012321", subdivision=2,
        velocity=62, octave=4, duration=TPQ)
    pad_chords(12, 8); bass_roots(12, 8)

    # coda: everything lets go
    melody(lead, 20, CODA)
    vibrato(lead, bar(20), bar(24), tempo_bpm=BPM, depth=0.35, rate=4.0)
    arp(harp, 20, CHORDS[20:24], pattern="0121", subdivision=2,
        velocity=48, octave=4, duration=TPQ)
    pad_chords(20, 4); bass_roots(20, 4)
    # final G(add9), long, soft
    for p in ("G2", "D3", "G3", "B3", "D4", "A4"):
        pad.note(bar(23), N(p), TPQ * 6, 45)
        harp.note(bar(23), N(p), TPQ * 6, 40)

    mf.add_track(lead); mf.add_track(pad); mf.add_track(harp); mf.add_track(bass)
    lead.marker(bar(4), "LOOP_START")
    lead.marker(bar(20), "LOOP_END")
    return mf


if __name__ == "__main__":
    mf = build()
    mf.write(OUT)
    d = verify(OUT, min_sec=50, max_sec=150)
    print("OK:", OUT)
    print("   duration:", d["duration_sec"], "s | notes:",
          sum(len(t["notes"]) for t in d["tracks"]),
          "| tracks:", len(d["tracks"]))