// The file listing and what the UI knows about each file. A leaf apart from
// util.js.

import {fileStartEpoch, fmtHM} from './util.js';

// Full listing from /api/files. Reassigned on every load; importers see the
// new array through the live binding.
export let allFiles = [];

// _idx is per filename and stable for the whole session: assigned the first
// time a name is seen and never reused. DOM ids (row-, pbtn-, aud-, …) are
// built from it, so they survive reloads — that is what lets a re-rendered day
// keep focus where it was. It used to be the position in the listing, which
// shifted on every rollover and left stored indexes pointing one row off.
const idxByName = new Map();
const stableIdx = name => {
  if (!idxByName.has(name)) idxByName.set(name, idxByName.size);
  return idxByName.get(name);
};

export function setFiles(list) {
  allFiles = list.map(f => ({...f, _idx: stableIdx(f.name)}));
}

export function removeFile(name) {
  allFiles = allFiles.filter(f => f.name !== name);
}

export const fileByName = name => allFiles.find(f => f.name === name) ?? null;
export const fileByIdx  = idx  => allFiles.find(f => f._idx === idx) ?? null;
// Queue entries carry the filename, never a row index; resolve at use time.
// Null when the file is gone from the current listing.
export const fileIdxByName = name => fileByName(name)?._idx ?? null;

export const isAnalysable = f => f.ext === 'wav' || f.ext === 'flac';

// idx -> [{start, end, score}], populated by analyse()
export const sectionMap = new Map();

// What a recording is called wherever it is spoken: its wall-clock span from
// the filename clock, "22:00 to 23:00". The filename itself ("20260523_220000")
// reads as a string of numbers. Non-standard names fall back to the name.
export function fileSpan(f) {
  const start = fileStartEpoch(f.date);
  if (start == null) return f.name;
  if (f.recording) return `${fmtHM(start)} to now`;
  if (f.duration == null) return fmtHM(start);
  return `${fmtHM(start)} to ${fmtHM(Math.round((start + f.duration) / 60) * 60)}`;
}