// The system-level report: does each episode keep time with its song
// (coupling) while still having dynamics the song does not explain
// (residual)? And do different songs — grown by different songs' laws —
// actually diverge? Outputs a table and out/report.md.

import { mkdirSync, writeFileSync } from 'node:fs';
import { resolve, dirname } from 'node:path';
import { fileURLToPath } from 'node:url';
import { loadSong } from './load.js';
import { Run } from '../src/film.js';
import { evaluate, fingerprint, divergence } from '../src/metrics.js';

const HERE = dirname(fileURLToPath(import.meta.url));
const ROOT = resolve(HERE, '..');
const BANK = resolve(ROOT, '../flow-state/test/songs');
const SEEDS = [999, 12345, 777777];

function args(argv) {
    const out = {};
    for (let i = 2; i < argv.length; i += 2) out[argv[i].replace(/^--/, '')] = argv[i + 1];
    return out;
}

const opt = args(process.argv);
const names = (opt.songs || 'drone,runner,dusk').split(',').map((s) => s.trim()).filter(Boolean);
const seeds = opt.seeds ? opt.seeds.split(',').map(Number) : SEEDS;
mkdirSync(resolve(ROOT, 'out'), { recursive: true });

const rows = [];
for (const name of names) {
    for (const seed of seeds) {
        const { song } = loadSong(resolve(BANK, `${name}.wav`), { fps: 30, seed });
        const run = new Run(song, { fps: 30, width: 480, height: 270, seed });
        run.simulate();
        const world = run.world;
        const m = evaluate(world, song);
        const fp = fingerprint(world);
        rows.push({
            song: name,
            seed,
            species: song.name,
            peak: world.stats().peak,
            pop: world.count,
            sortCount: song.events.length,
            hue: Number(song.palette.hue.toFixed(2)),
            ...m,
            fp,
        });
    }
}

const md = [];

md.push('# metabolism — song × seed report');
md.push('');
md.push(`Generated ${new Date().toISOString().slice(0, 10)} · 3 test signals (${names.join(', ')}) × ${seeds.length} seeds each.`);
md.push('');
md.push('| song | seed | species | peak | pop | coupling | residual | **fitness** | hue |');
md.push('|---|---|---|---|---|---|---|---|---|');
for (const r of rows) {
    md.push(`| ${r.song} | ${r.seed} | ${r.species} | ${r.peak} | ${r.pop} | ${fps2(r.coupling)} | ${fps2(r.residual)} | **${fps2(r.fitness)}** | ${r.hue} |`);
}

md.push('');
md.push('## Grown structure (average over seeds)');
md.push('');
md.push('| song | occupancy | cluster | trailFill | class mix b/f/s |');
md.push('|---|---|---|---|---|');
const bySong = new Map();
for (const r of rows) {
    if (!bySong.has(r.song)) bySong.set(r.song, []);
    bySong.get(r.song).push(r);
}
for (const name of names) {
    const list = bySong.get(name) || [];
    const avg = {
        occupancy: (list.reduce((s, r) => s + r.fp.occupancy, 0) / list.length).toFixed(3),
        cluster: (list.reduce((s, r) => s + r.fp.cluster, 0) / list.length).toFixed(2),
        trailFill: (list.reduce((s, r) => s + r.fp.trailFill, 0) / list.length).toFixed(3),
        mix: [0, 1, 2].map((i) =>
            (list.reduce((s, r) => s + r.fp.classMix[i], 0) / list.length).toFixed(2)
        ).join('/'),
    };
    md.push(`| ${name} | ${avg.occupancy} | ${avg.cluster} | ${avg.trailFill} | ${avg.mix} |`);
}

md.push('');
md.push('## Divergence (L1 distance between fingerprints)');
md.push('');
md.push('Across songs (seed 12345 each):');
md.push('');
md.push('| pair | divergence |');
md.push('|---|---|');
const songs = [...new Set(rows.map((r) => r.song))];
const char = (song, seed) => rows.find((r) => r.song === song && r.seed === seed).fp;
for (let i = 0; i < songs.length; i++) {
    for (let j = i + 1; j < songs.length; j++) {
        const d = divergence(char(songs[i], 12345), char(songs[j], 12345));
        md.push(`| ${songs[i]} ↔ ${songs[j]} | ${fps2(d)} |`);
    }
}
md.push('');
md.push('Across seeds (drone):');
md.push('');
md.push('| pair | divergence |');
md.push('|---|---|');
for (let i = 0; i < seeds.length; i++) {
    for (let j = i + 1; j < seeds.length; j++) {
        const d = divergence(char('drone', seeds[i]), char('drone', seeds[j]));
        md.push(`| seed ${seeds[i]} ↔ ${seeds[j]} | ${fps2(d)} |`);
    }
}

md.push('');
md.push('_Note: coupling is correlation with the song envelope, residual is 1 − R² after');
md.push('regressing out song features; fitness is a blend of both. See src/metrics.js._');

const text = md.join('\n') + '\n';
const reportFile = resolve(ROOT, 'out', 'report.md');
writeFileSync(reportFile, text);
writeFileSync(resolve(ROOT, 'out', 'report.json'), JSON.stringify(rows, null, 2));

console.log(text);
console.log('wrote ' + reportFile);

function fps2(v) {
    return v.toFixed(3).replace('-', '−');
}