47 lines
1.3 KiB
TypeScript
47 lines
1.3 KiB
TypeScript
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/**
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* Cross-platform crypto utilities
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* Provides hashing functions that work in both Node.js and browser environments
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*/
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/**
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* Simple string hash function that works in all environments
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* Uses djb2 algorithm - fast and good distribution
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* @param str - String to hash
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* @returns Positive integer hash
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*/
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export function hashString(str: string): number {
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let hash = 5381
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for (let i = 0; i < str.length; i++) {
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const char = str.charCodeAt(i)
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hash = ((hash << 5) + hash) + char // hash * 33 + char
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}
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// Ensure positive number
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return Math.abs(hash)
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}
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/**
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* Alternative: FNV-1a hash algorithm
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* Good distribution and fast
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* @param str - String to hash
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* @returns Positive integer hash
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*/
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export function fnv1aHash(str: string): number {
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let hash = 2166136261
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for (let i = 0; i < str.length; i++) {
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hash ^= str.charCodeAt(i)
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hash = (hash * 16777619) >>> 0
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}
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return hash
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}
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/**
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* Generate a deterministic hash for partitioning
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* Uses the most appropriate algorithm for the environment
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* @param input - Input string to hash
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* @returns Positive integer hash suitable for modulo operations
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*/
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export function getPartitionHash(input: string): number {
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// Use djb2 by default as it's fast and has good distribution
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// This ensures consistent partitioning across all environments
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return hashString(input)
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}
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