#lang pollen/mode racket/base
; SPDX-License-Identifier: BlueOak-1.0.0
; This file is licensed under the Blue Oak Model License 1.0.0.
;; Builds an HTML page containing the keyword index for all ◊index entries in
;; the articles, by pulling them out of the SQLite cache DB.
(require racket/match
racket/list
racket/file
db/base
net/uri-codec
pollen/template)
(require "crystalize.rkt"
"snippets-html.rkt")
(provide main)
;; Get the index entries from the SQLite cache, return them as a list of vectors
(define (fetch-entries)
(define q
◊string-append{
SELECT entry, subentry, a.rowid, "/" || k.pagenode || "#" || anchor AS href, title_plain
FROM keywordindex k INNER JOIN articles a
ON a.pagenode = k.pagenode
ORDER BY entry COLLATE NOCASE ASC;})
(query-rows (sqltools:dbc) q))
;; Convert a vector (row) into a txexpr representing a link to the original article
(define (make-link row)
`(a [[href ,(vector-ref row 3)]
[title ,(vector-ref row 4)]]
,(number->string (vector-ref row 2))))
;(require sugar/debug)
;; Convert a list of vectors from the cache DB into a list of the form:
;; (list (cons FIRST-LETTER
;; (list (cons KEYWORD
;; (list LINKS ...))
;; ...))
;; ...)
(define (group-entries data)
(define collated-list
(for/fold ([entry-table null]
#:result (reverse entry-table))
([row (in-list data)])
(define this-entry (vector-ref row 0))
(cond [(and (not (null? entry-table))
(string-ci=? (first (first entry-table)) this-entry))
(match-define (cons (list last-entry last-list) rest-entries) entry-table)
(cons `(,last-entry ,(append last-list (list (make-link row)))) rest-entries)]
[else
(cons `(,this-entry ,(list (make-link row)))
entry-table)])))
(define (first-letter entry)
(char-upcase (first (string->list (first entry)))))
(for/list ([letter-group (in-list (group-by first-letter collated-list))])
(list (first-letter (first letter-group)) letter-group)))
(define (entry+links->txexpr entry)
(match-define (list entry-word links) entry)
`(li [[id ,(uri-encode (string-downcase entry-word))]]
,entry-word nbsp
,@(add-between links ", ")))
;; Return the complete HTML for the keyword index. Each letter group begins with a heading for the
;; letter, followed by a definition list for its entries.
(define (html$-index entries)
(define groups
(for/list ([letter-group (in-list entries)])
(match-define (list letter-char entries) letter-group)
`(section (h2 ,(list->string (list letter-char)))
(ul ,@(map entry+links->txexpr entries)))))
(apply string-append (map ->html groups)))
(define (html$-keywordindex-page the-index)
◊string-append{
<!DOCTYPE html>
<html lang="en">
◊html$-page-head{The Local Yarn: Keyword Index}
◊html$-page-body-open[]
<div id="keywordindex">
◊the-index
</div>
◊html$-page-body-close[]
</html>})
(define (main)
(spell-of-summoning!) ; Turn on DB
(displayln "Writing keyword-index.html…")
(display-to-file (html$-keywordindex-page (html$-index (group-entries (fetch-entries))))
"keyword-index.html"
#:mode 'text
#:exists 'replace))
