Update book finder and cover matching - includes LibGen provider

server/BookFinder.js

@@ -1,5 +1,7 @@
 const OpenLibrary = require('./providers/OpenLibrary')
 const LibGen = require('./providers/LibGen')
+const Logger = require('./Logger')
+const { levenshteinDistance } = require('./utils/index')
 
 class BookFinder {
   constructor() {
@@ -15,19 +17,142 @@ class BookFinder {
     return book
   }
 
-  async search(query, provider = 'openlibrary') {
-    var books = null
+  stripSubtitle(title) {
+    if (title.includes(':')) {
+      return title.split(':')[0].trim()
+    } else if (title.includes(' - ')) {
+      return title.split(' - ')[0].trim()
+    }
+    return title
+  }
+
+  cleanTitleForCompares(title) {
+    // Remove subtitle if there (i.e. "Cool Book: Coolest Ever" becomes "Cool Book")
+    var stripped = this.stripSubtitle(title)
+
+    // Remove text in paranthesis (i.e. "Ender's Game (Ender's Saga)" becomes "Ender's Game")
+    var cleaned = stripped.replace(/ *\([^)]*\) */g, "")
+
+    // Remove single quotes (i.e. "Ender's Game" becomes "Enders Game")
+    cleaned = cleaned.replace(/'/g, '')
+    return cleaned.toLowerCase()
+  }
+
+  filterSearchResults(books, title, author, maxTitleDistance, maxAuthorDistance) {
+    var searchTitle = this.cleanTitleForCompares(title)
+    return books.map(b => {
+      b.cleanedTitle = this.cleanTitleForCompares(b.title)
+      b.titleDistance = levenshteinDistance(b.cleanedTitle, title)
+      if (author) {
+        b.authorDistance = levenshteinDistance(b.author || '', author)
+      }
+      b.totalDistance = b.titleDistance + (b.authorDistance || 0)
+      b.totalPossibleDistance = b.title.length
+
+      if (b.cleanedTitle.includes(searchTitle) && searchTitle.length > 4) {
+        b.includesSearch = searchTitle
+      } else if (b.title.includes(searchTitle) && searchTitle.length > 4) {
+        b.includesSearch = searchTitle
+      }
+
+      if (author && b.author) b.totalPossibleDistance += b.author.length
+
+      return b
+    }).filter(b => {
+      if (b.includesSearch) { // If search was found in result title exactly then skip over leven distance check
+        Logger.debug(`Exact search was found inside title ${b.cleanedTitle}/${b.includesSearch}`)
+      } else if (b.titleDistance > maxTitleDistance) {
+        Logger.debug(`Filtering out search result title distance = ${b.titleDistance}: "${b.cleanedTitle}"/"${searchTitle}"`)
+        return false
+      }
+
+      if (author && b.authorDistance > maxAuthorDistance) {
+        Logger.debug(`Filtering out search result "${b.title}", author distance = ${b.authorDistance}: "${b.author}"/"${author}"`)
+        return false
+      }
+
+      if (b.totalPossibleDistance < 4 && b.totalDistance > 0) return false
+      return true
+    })
+  }
+
+  async getLibGenResults(title, author, maxTitleDistance, maxAuthorDistance) {
+    var books = await this.libGen.search(title)
+    Logger.info(`LibGen Book Search Results: ${books.length || 0}`)
+    if (books.errorCode) {
+      Logger.error(`LibGen Search Error ${books.errorCode}`)
+      return []
+    }
+    var booksFiltered = this.filterSearchResults(books, title, author, maxTitleDistance, maxAuthorDistance)
+    if (!booksFiltered.length && books.length) {
+      Logger.info(`Search has ${books.length} matches, but no close title matches`)
+    }
+    return booksFiltered
+  }
+
+  async getOpenLibResults(title, author, maxTitleDistance, maxAuthorDistance) {
+    var books = await this.openLibrary.searchTitle(title)
+    Logger.info(`OpenLib Book Search Results: ${books.length || 0}`)
+    if (books.errorCode) {
+      Logger.error(`OpenLib Search Error ${books.errorCode}`)
+      return []
+    }
+    var booksFiltered = this.filterSearchResults(books, title, author, maxTitleDistance, maxAuthorDistance)
+    if (!booksFiltered.length && books.length) {
+      Logger.info(`Search has ${books.length} matches, but no close title matches`)
+    }
+    return booksFiltered
+  }
+
+  async search(provider, title, author, options = {}) {
+    var books = []
+    var maxTitleDistance = !isNaN(options.titleDistance) ? Number(options.titleDistance) : 4
+    var maxAuthorDistance = !isNaN(options.authorDistance) ? Number(options.authorDistance) : 4
+    Logger.info(`Book Search, title: "${title}", author: "${author}", provider: ${provider}`)
 
     if (provider === 'libgen') {
-      books = await this.libGen.search(query)
-      return books
+      books = await this.getLibGenResults(title, author, maxTitleDistance, maxAuthorDistance)
+    } else if (provider === 'openlibrary') {
+      books = await this.getOpenLibResults(title, author, maxTitleDistance, maxAuthorDistance)
+    } else if (provider === 'all') {
+      var lbBooks = await this.getLibGenResults(title, author, maxTitleDistance, maxAuthorDistance)
+      var olBooks = await this.getOpenLibResults(title, author, maxTitleDistance, maxAuthorDistance)
+      books = books.concat(lbBooks, olBooks)
+    } else {
+      var olBooks = await this.getOpenLibResults(title, author, maxTitleDistance, maxAuthorDistance)
+      var hasCloseMatch = olBooks.find(b => (b.totalDistance < 4 && b.totalPossibleDistance > 4))
+      if (hasCloseMatch) {
+        books = olBooks
+      } else {
+        Logger.info(`Book Search, LibGen has no close matches - get openlib results also`)
+        var lbBooks = await this.getLibGenResults(title, author, maxTitleDistance, maxAuthorDistance)
+        books = books.concat(lbBooks)
+      }
+
+      if (!books.length && author) {
+        Logger.info(`Book Search, no matches for title and author.. check title only`)
+        return this.search(provider, title, null, options)
+      }
     }
 
-    books = await this.openLibrary.search(query)
-    if (books.errorCode) {
-      console.error('Books not found')
-    }
-    return books
+    return books.sort((a, b) => {
+      return a.totalDistance - b.totalDistance
+    })
+  }
+
+  async findCovers(provider, title, author, options = {}) {
+    var searchResults = await this.search(provider, title, author, options)
+    console.log('Find Covers search results', searchResults)
+    var covers = []
+    searchResults.forEach((result) => {
+      if (result.covers && result.covers.length) {
+        covers = covers.concat(result.covers)
+      }
+      if (result.cover) {
+        covers.push(result.cover)
+      }
+    })
+    return covers
   }
 }
 module.exports = BookFinder