Move internal packages to an internal folder

For reference: https://go.dev/doc/go1.4#internalpackages

internal/reader/rewrite/rewriter.go

@@ -0,0 +1,127 @@
+// SPDX-FileCopyrightText: Copyright The Miniflux Authors. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package rewrite // import "miniflux.app/v2/internal/reader/rewrite"
+
+import (
+	"strconv"
+	"strings"
+	"text/scanner"
+
+	"miniflux.app/v2/internal/logger"
+	"miniflux.app/v2/internal/model"
+	"miniflux.app/v2/internal/url"
+)
+
+type rule struct {
+	name string
+	args []string
+}
+
+// Rewriter modify item contents with a set of rewriting rules.
+func Rewriter(entryURL string, entry *model.Entry, customRewriteRules string) {
+	rulesList := getPredefinedRewriteRules(entryURL)
+	if customRewriteRules != "" {
+		rulesList = customRewriteRules
+	}
+
+	rules := parseRules(rulesList)
+	rules = append(rules, rule{name: "add_pdf_download_link"})
+
+	logger.Debug(`[Rewrite] Applying rules %v for %q`, rules, entryURL)
+
+	for _, rule := range rules {
+		applyRule(entryURL, entry, rule)
+	}
+}
+
+func parseRules(rulesText string) (rules []rule) {
+	scan := scanner.Scanner{Mode: scanner.ScanIdents | scanner.ScanStrings}
+	scan.Init(strings.NewReader(rulesText))
+
+	for {
+		switch scan.Scan() {
+		case scanner.Ident:
+			rules = append(rules, rule{name: scan.TokenText()})
+
+		case scanner.String:
+			if l := len(rules) - 1; l >= 0 {
+				text := scan.TokenText()
+				text, _ = strconv.Unquote(text)
+
+				rules[l].args = append(rules[l].args, text)
+			}
+
+		case scanner.EOF:
+			return
+		}
+	}
+}
+
+func applyRule(entryURL string, entry *model.Entry, rule rule) {
+	switch rule.name {
+	case "add_image_title":
+		entry.Content = addImageTitle(entryURL, entry.Content)
+	case "add_mailto_subject":
+		entry.Content = addMailtoSubject(entryURL, entry.Content)
+	case "add_dynamic_image":
+		entry.Content = addDynamicImage(entryURL, entry.Content)
+	case "add_youtube_video":
+		entry.Content = addYoutubeVideo(entryURL, entry.Content)
+	case "add_invidious_video":
+		entry.Content = addInvidiousVideo(entryURL, entry.Content)
+	case "add_youtube_video_using_invidious_player":
+		entry.Content = addYoutubeVideoUsingInvidiousPlayer(entryURL, entry.Content)
+	case "add_youtube_video_from_id":
+		entry.Content = addYoutubeVideoFromId(entry.Content)
+	case "add_pdf_download_link":
+		entry.Content = addPDFLink(entryURL, entry.Content)
+	case "nl2br":
+		entry.Content = replaceLineFeeds(entry.Content)
+	case "convert_text_link", "convert_text_links":
+		entry.Content = replaceTextLinks(entry.Content)
+	case "fix_medium_images":
+		entry.Content = fixMediumImages(entryURL, entry.Content)
+	case "use_noscript_figure_images":
+		entry.Content = useNoScriptImages(entryURL, entry.Content)
+	case "replace":
+		// Format: replace("search-term"|"replace-term")
+		if len(rule.args) >= 2 {
+			entry.Content = replaceCustom(entry.Content, rule.args[0], rule.args[1])
+		} else {
+			logger.Debug("[Rewrite] Cannot find search and replace terms for replace rule %s", rule)
+		}
+	case "remove":
+		// Format: remove("#selector > .element, .another")
+		if len(rule.args) >= 1 {
+			entry.Content = removeCustom(entry.Content, rule.args[0])
+		} else {
+			logger.Debug("[Rewrite] Cannot find selector for remove rule %s", rule)
+		}
+	case "add_castopod_episode":
+		entry.Content = addCastopodEpisode(entryURL, entry.Content)
+	case "base64_decode":
+		if len(rule.args) >= 1 {
+			entry.Content = applyFuncOnTextContent(entry.Content, rule.args[0], decodeBase64Content)
+		} else {
+			entry.Content = applyFuncOnTextContent(entry.Content, "body", decodeBase64Content)
+		}
+	case "parse_markdown":
+		entry.Content = parseMarkdown(entry.Content)
+	case "remove_tables":
+		entry.Content = removeTables(entry.Content)
+	case "remove_clickbait":
+		entry.Title = removeClickbait(entry.Title)
+	}
+}
+
+func getPredefinedRewriteRules(entryURL string) string {
+	urlDomain := url.Domain(entryURL)
+	for domain, rules := range predefinedRules {
+		if strings.Contains(urlDomain, domain) {
+			return rules
+		}
+	}
+
+	return ""
+}