Extended Search

interface ExtendedSearchOptions {
  /** Enable unix-like search commands (default: false) */
  useExtendedSearch?: boolean;
}

import Fuse from "fuse.js";

// Enable extended search
const fuse = new Fuse(books, {
  keys: ["title", "author"],
  useExtendedSearch: true
});

// Now you can use extended search syntax
const results = fuse.search("'javascript"); // Fuzzy match
const exact = fuse.search('"JavaScript"'); // Exact match
const prefix = fuse.search("^Java"); // Prefix match

type Expression =
  | { [key: string]: string }
  | { $path: ReadonlyArray<string>; $val: string }
  | { $and?: Expression[] }
  | { $or?: Expression[] };

// Field-specific search
const fieldResults = fuse.search({
  title: "javascript",
  author: "crockford"
});

// Path-based search for nested fields
const pathResults = fuse.search({
  $path: ["author", "name"],
  $val: "douglas"
});

// AND logic - all conditions must match
const andResults = fuse.search({
  $and: [
    { title: "javascript" },
    { author: "crockford" },
    { year: "2008" }
  ]
});

// OR logic - any condition can match
const orResults = fuse.search({
  $or: [
    { title: "javascript" },
    { title: "python" },
    { title: "ruby" }
  ]
});

// Complex nested logic
const complexResults = fuse.search({
  $and: [
    {
      $or: [
        { title: "javascript" },
        { title: "typescript" }
      ]
    },
    { author: "crockford" }
  ]
});

// Exact match - must match exactly
const exactResults = fuse.search('"javascript"');

// Fuzzy match (default behavior, explicit)
const fuzzyResults = fuse.search("'javascript");

// Prefix match - starts with pattern
const prefixResults = fuse.search("^java");

// Suffix match - ends with pattern  
const suffixResults = fuse.search("script$");

// Inverse match - does NOT contain pattern
const inverseResults = fuse.search("!php");

// Include match - must contain pattern
const includeResults = fuse.search("=javascript");

const books = [
  { title: "JavaScript: The Good Parts", author: "Douglas Crockford" },
  { title: "TypeScript Handbook", author: "Microsoft" },
  { title: "Java: The Complete Reference", author: "Herbert Schildt" },
  { title: "Python Programming", author: "Mark Lutz" }
];

const fuse = new Fuse(books, {
  keys: ["title", "author"],
  useExtendedSearch: true
});

// Exact title match
const exact = fuse.search('"JavaScript: The Good Parts"');

// All books starting with "Java"
const javaBooks = fuse.search("^Java");

// All books ending with "Handbook"
const handbooks = fuse.search("Handbook$");

// All books NOT about Python
const nonPython = fuse.search("!Python");

// All books that must contain "Script"
const scriptBooks = fuse.search("=Script");

// Exact match in specific field
const exactAuthor = fuse.search({
  author: '"Douglas Crockford"'
});

// Prefix match in title field
const titlePrefix = fuse.search({
  title: "^JavaScript"
});

// Multiple fields with different patterns
const mixedSearch = fuse.search({
  $and: [
    { title: "^Java" },        // Title starts with "Java"
    { author: "!Microsoft" }   // Author is not Microsoft
  ]
});

// Complex field patterns
const complexField = fuse.search({
  $or: [
    { title: '"Complete Reference"' },  // Exact title match
    { author: "=Crockford" }           // Author contains "Crockford"
  ]
});

const products = [
  {
    name: "JavaScript Book",
    details: {
      category: "Programming",
      language: "English",
      tags: ["js", "programming", "web"]
    }
  }
];

const fuse = new Fuse(products, {
  keys: ["name", "details.category", "details.tags"],
  useExtendedSearch: true
});

// Exact category match
const categoryResults = fuse.search({
  "details.category": '"Programming"'
});

// Prefix search in nested field
const nestedPrefix = fuse.search({
  $path: ["details", "language"],
  $val: "^Eng"
});

// Complex nested search
const nestedComplex = fuse.search({
  $and: [
    { name: "=JavaScript" },
    { "details.category": '"Programming"' },
    { "details.tags": "!python" }
  ]
});

// These will throw errors if extended search is not enabled:

try {
  const fuse = new Fuse(data, { useExtendedSearch: false });
  fuse.search({ $and: [{ title: "test" }] }); // Throws error
} catch (error) {
  console.error("Extended search not enabled");
}

try {
  fuse.search('"exact match"'); // May work depending on implementation
} catch (error) {
  console.error("Extended search syntax not available");
}

// Safe extended search usage
function safeExtendedSearch(fuse, query) {
  try {
    return fuse.search(query);
  } catch (error) {
    if (error.message.includes("EXTENDED_SEARCH_UNAVAILABLE")) {
      console.warn("Extended search not available, falling back to basic search");
      // Convert extended query to basic search if possible
      const basicQuery = typeof query === "string" ? query.replace(/['"^$!=]/g, "") : "";
      return fuse.search(basicQuery);
    }
    throw error;
  }
}

// Check if extended search is enabled
function supportsExtendedSearch(fuse) {
  try {
    fuse.search({ $and: [] });
    return true;
  } catch {
    return false;
  }
}

// Logical expressions are more expensive than simple searches
const simple = fuse.search("javascript");        // Fast
const logical = fuse.search({                    // Slower
  $and: [
    { title: "javascript" },
    { author: "crockford" }
  ]
});

// Exact matches can be faster than fuzzy matches
const fuzzy = fuse.search("'javascript");        // Normal fuzzy search
const exact = fuse.search('"JavaScript"');       // Potentially faster

// Complex nested logic impacts performance
const complex = fuse.search({                    // Slowest
  $or: [
    {
      $and: [
        { title: "^Java" },
        { author: "!Microsoft" }
      ]
    },
    {
      $and: [
        { title: "=Script" },
        { category: '"Programming"' }
      ]
    }
  ]
});