/**
 * Stable gradient + accent derived from a game id. Used as cover-art fallback
 * when the backend has no thumbnail for a game.
 */
export interface CoverColors {
    c1: string;
    c2: string;
    accent: string;
    angle: number;
    blobX: number;
    blobY: number;
}

const PALETTE: Array<Pick<CoverColors, 'c1' | 'c2' | 'accent'>> = [
    { c1: '#7c2d12', c2: '#1c1917', accent: '#fbbf24' },
    { c1: '#1e40af', c2: '#0c1f3a', accent: '#22d3ee' },
    { c1: '#15803d', c2: '#052e16', accent: '#fef08a' },
    { c1: '#7f1d1d', c2: '#0a0a0a', accent: '#f97316' },
    { c1: '#1d4ed8', c2: '#0c1f3a', accent: '#f59e0b' },
    { c1: '#a16207', c2: '#422006', accent: '#fde047' },
    { c1: '#3f3f46', c2: '#0a0a0a', accent: '#22d3ee' },
    { c1: '#ea580c', c2: '#1e293b', accent: '#22d3ee' },
    { c1: '#064e3b', c2: '#020617', accent: '#34d399' },
    { c1: '#1e3a8a', c2: '#172554', accent: '#22d3ee' },
];

const hash = (id: string): number => {
    let h = 0;
    for (let i = 0; i < id.length; i++) h = (h * 31 + id.charCodeAt(i)) >>> 0;
    return h;
};

export const coverColorsFor = (id: string): CoverColors => {
    const h = hash(id);
    const base = PALETTE[h % PALETTE.length];
    return {
        ...base,
        angle: 110 + (h % 60),
        blobX: 60 + (h % 30),
        blobY: 10 + ((h * 7) % 30),
    };
};

export const titleFontSize = (
    title: string,
    aspect: 'box' | 'square' | 'banner',
): number => {
    const len = title.length;
    if (aspect === 'banner' || aspect === 'square') {
        if (len > 22) return 18;
        if (len > 14) return 22;
        return 28;
    }
    if (len > 26) return 15;
    if (len > 20) return 17;
    if (len > 14) return 21;
    return 26;
};