/**
* Pure helpers + constants for layers and adjustment sub-layers.
*
* Everything in this module is stateless — feed in a layer object and
* get back a value. The legacy gallery editor's module-level helpers
* re-export from here so existing call sites keep working unchanged.
*/
/** True if the layer has at least one FX/adjustment sub-layer. */
export function layerHasAdjustments(layer) {
return !!(layer && layer.adjLayers && layer.adjLayers.length > 0);
}
/**
* True if the layer carries a non-identity Levels OR Color-Balance
* adjustment that needs the per-pixel pass (vs the cheap CSS-filter
* path for plain B/C/H/S).
*/
export function layerNeedsPixelPass(layer) {
if (!layer || !layer.adjustments) return false;
const a = layer.adjustments;
if (a.levels && (a.levels.inBlack !== 0 || a.levels.inWhite !== 255 ||
a.levels.gamma !== 1 ||
a.levels.outBlack !== 0 || a.levels.outWhite !== 255)) return true;
if (a.colorBalance) {
for (const tone of ['shadows', 'midtones', 'highlights']) {
const v = a.colorBalance[tone];
if (v && (v.r || v.g || v.b)) return true;
}
}
return false;
}
/**
* Compact hash of a layer's Levels + Color-Balance values. Used to
* key the per-pixel adjustment cache so we can skip recomputing when
* nothing changed.
*/
export function adjustmentsKey(adj) {
const l = adj.levels || {};
const cb = adj.colorBalance || {};
const s = cb.shadows || {}, m = cb.midtones || {}, h = cb.highlights || {};
return [
l.inBlack|0, l.inWhite|0, l.gamma || 1, l.outBlack|0, l.outWhite|0,
s.r|0, s.g|0, s.b|0, m.r|0, m.g|0, m.b|0, h.r|0, h.g|0, h.b|0,
].join('|');
}
/** Identity params for each adjustment type. */
export function defaultAdjParams(type) {
switch (type) {
case 'brightness-contrast': return { brightness: 1, contrast: 1 };
case 'exposure': return { exposure: 0, offset: 0, gamma: 1 };
case 'white-balance': return { temperature: 0, tint: 0 };
case 'hue-saturation': return { hue: 0, saturation: 1, lightness: 0 };
case 'vibrance': return { vibrance: 0 };
case 'black-white': return { red: 30, green: 59, blue: 11, constant: 0 };
case 'shadows-highlights': return { shadows: 0, highlights: 0 };
case 'levels': return {
channel: 'rgb',
inBlack: 0, inWhite: 255, gamma: 1.0, outBlack: 0, outWhite: 255,
channels: {
red: { inBlack: 0, inWhite: 255, gamma: 1.0, outBlack: 0, outWhite: 255 },
green: { inBlack: 0, inWhite: 255, gamma: 1.0, outBlack: 0, outWhite: 255 },
blue: { inBlack: 0, inWhite: 255, gamma: 1.0, outBlack: 0, outWhite: 255 },
},
};
case 'curves': return {
channel: 'rgb',
points: {
rgb: [[0, 0], [255, 255]],
red: [[0, 0], [255, 255]],
green: [[0, 0], [255, 255]],
blue: [[0, 0], [255, 255]],
},
};
case 'color-balance': return {
shadows: { r: 0, g: 0, b: 0 },
midtones: { r: 0, g: 0, b: 0 },
highlights: { r: 0, g: 0, b: 0 },
};
case 'selective-color': return {
range: 'reds',
ranges: Object.fromEntries(
['reds', 'yellows', 'greens', 'cyans', 'blues', 'magentas', 'neutrals', 'blacks']
.map(name => [name, { cyan: 0, magenta: 0, yellow: 0, black: 0 }]),
),
};
case 'gradient-map': return {
shadows: '#000000',
highlights: '#ffffff',
midpoint: 50,
reverse: false,
};
}
return {};
}
/** Preset names for the retained adjustment popup. */
export function adjustmentPresetOptions(type) {
const options = {
'brightness-contrast': ['Default', 'High Contrast'],
'exposure': ['Default', 'Lift Exposure', 'Lower Exposure'],
'white-balance': ['Default', 'Warm', 'Cool'],
'hue-saturation': ['Default', 'Desaturate', 'Boost Color'],
'vibrance': ['Default', 'Muted', 'Color Pop'],
'black-white': ['Default', 'High Contrast'],
'shadows-highlights': ['Default', 'Lift Shadows', 'Recover Highlights'],
'levels': ['Default', 'Auto Contrast'],
'curves': ['Default', 'S-Curve'],
'color-balance': ['Default', 'Warm Highlights', 'Cool Shadows'],
'selective-color': ['Default', 'Deep Reds'],
'gradient-map': ['Default', 'Warm Tone', 'Cool Tone'],
};
return options[type] || ['Default'];
}
/** Return a fresh parameter object for a named adjustment preset. */
export function adjustmentPresetParams(type, preset) {
const params = defaultAdjParams(type);
switch (`${type}:${preset}`) {
case 'brightness-contrast:High Contrast':
return { ...params, contrast: 1.28 };
case 'exposure:Lift Exposure':
return { ...params, exposure: 0.45 };
case 'exposure:Lower Exposure':
return { ...params, exposure: -0.45 };
case 'white-balance:Warm':
return { ...params, temperature: 35 };
case 'white-balance:Cool':
return { ...params, temperature: -35 };
case 'hue-saturation:Desaturate':
return { ...params, saturation: 0.35 };
case 'hue-saturation:Boost Color':
return { ...params, saturation: 1.35 };
case 'vibrance:Muted':
return { ...params, vibrance: -30 };
case 'vibrance:Color Pop':
return { ...params, vibrance: 45 };
case 'black-white:High Contrast':
return { ...params, red: 38, green: 54, blue: 8, constant: 0 };
case 'shadows-highlights:Lift Shadows':
return { ...params, shadows: 38 };
case 'shadows-highlights:Recover Highlights':
return { ...params, highlights: -38 };
case 'levels:Auto Contrast':
return { ...params, inBlack: 12, inWhite: 243 };
case 'curves:S-Curve':
return { ...params, points: { ...params.points, rgb: [[0, 12], [76, 64], [178, 194], [255, 243]] } };
case 'color-balance:Warm Highlights':
return { ...params, highlights: { r: 16, g: 4, b: -14 } };
case 'color-balance:Cool Shadows':
return { ...params, shadows: { r: -12, g: 3, b: 16 } };
case 'selective-color:Deep Reds':
return { ...params, ranges: { ...params.ranges, reds: { ...params.ranges.reds, black: -18 } } };
case 'gradient-map:Warm Tone':
return { ...params, shadows: '#21151a', highlights: '#ffd59a' };
case 'gradient-map:Cool Tone':
return { ...params, shadows: '#101c36', highlights: '#d8f2ff' };
default:
return params;
}
}
/** Human-readable name for an adjustment type. */
export function adjLayerLabel(type) {
return {
'brightness-contrast': 'Brightness/Contrast',
'exposure': 'Exposure',
'white-balance': 'White Balance',
'hue-saturation': 'Hue/Saturation',
'vibrance': 'Vibrance',
'black-white': 'Black & White',
'shadows-highlights': 'Shadows/Highlights',
'levels': 'Levels',
'curves': 'Curves',
'color-balance': 'Color Balance',
'selective-color': 'Selective Color',
'gradient-map': 'Gradient Map',
}[type] || type;
}
/**
* Per-type SVG icon strings. Used in popup title bars, the minimised
* FX-dock chips, and the layer-panel sub-row name so the same glyph
* shows up everywhere a given adjustment type appears.
*/
export const ADJ_ICONS = {
'brightness-contrast': '',
'exposure': '',
'white-balance': '',
'hue-saturation': '',
'vibrance': '',
'black-white': '',
'shadows-highlights': '',
'levels': '',
'curves': '',
'color-balance': '',
'selective-color': '',
'gradient-map': '',
};
/** SVG used in the topbar/history button glyphs. */
export const HISTORY_ICON = '';
/** Quick downsampled-alpha check: are there any opaque pixels on this canvas? */
export function isMaskCanvasEmpty(canvas) {
if (!canvas) return true;
try {
const w = canvas.width, h = canvas.height;
if (!w || !h) return true;
const sw = Math.min(200, w), sh = Math.min(200, h);
const tmp = document.createElement('canvas');
tmp.width = sw; tmp.height = sh;
tmp.getContext('2d').drawImage(canvas, 0, 0, sw, sh);
const d = tmp.getContext('2d').getImageData(0, 0, sw, sh).data;
for (let i = 3; i < d.length; i += 4) if (d[i] > 0) return false;
return true;
} catch { return false; }
}
/** Same as `isMaskCanvasEmpty` but accepts a layer wrapper. */
export function isLayerEmpty(layer) {
if (!layer || !layer.canvas) return true;
return isMaskCanvasEmpty(layer.canvas);
}
/**
* Compact "now / 30s / 12m / 4h" relative-time string. Used in the
* editor's history panel labels.
*/
export function relTime(ts) {
if (!ts) return '';
const dt = (Date.now() - ts) / 1000;
if (dt < 5) return 'now';
if (dt < 60) return Math.round(dt) + 's';
if (dt < 3600) return Math.round(dt / 60) + 'm';
return Math.round(dt / 3600) + 'h';
}