Add social sharing functionality

lib/social_share_button_helper.rb

@@ -0,0 +1,51 @@
+module SocialShareButtonHelper
+  require "uri"
+
+  SOCIAL_SHARE_CONFIG = {
+    :email => "social_icons/email.svg",
+    :facebook => "social_icons/facebook.svg",
+    :linkedin => "social_icons/linkedin.svg",
+    :mastodon => "social_icons/mastodon.svg",
+    :telegram => "social_icons/telegram.svg",
+    :x => "social_icons/x.svg"
+  }.freeze
+
+  def self.filter_allowed_sites(sites)
+    valid_sites = sites.empty? ? SOCIAL_SHARE_CONFIG.keys : sites.select { |site| valid_site?(site) }
+    invalid_sites = sites - valid_sites
+    [valid_sites, invalid_sites]
+  end
+
+  def self.icon_path(site)
+    SOCIAL_SHARE_CONFIG[site.to_sym] || ""
+  end
+
+  def self.valid_site?(site)
+    SOCIAL_SHARE_CONFIG.key?(site.to_sym)
+  end
+
+  def self.generate_share_url(site, params)
+    site = site.to_sym
+    case site
+    when :email
+      to = params[:to] || ""
+      subject = CGI.escape(params[:title])
+      body = CGI.escape(params[:url])
+      "mailto:#{to}?subject=#{subject}&body=#{body}"
+    when :x
+      via_str = params[:via] ? "&via=#{URI.encode_www_form_component(params[:via])}" : ""
+      hashtags_str = params[:hashtags] ? "&hashtags=#{URI.encode_www_form_component(params[:hashtags].join(','))}" : ""
+      "https://x.com/intent/tweet?url=#{URI.encode_www_form_component(params[:url])}&text=#{URI.encode_www_form_component(params[:title])}#{hashtags_str}#{via_str}"
+    when :linkedin
+      "https://www.linkedin.com/sharing/share-offsite/?url=#{URI.encode_www_form_component(params[:url])}"
+    when :facebook
+      "https://www.facebook.com/sharer/sharer.php?u=#{URI.encode_www_form_component('params[:url]')}&t=#{URI.encode_www_form_component(params[:title])}"
+    when :mastodon
+      "https://mastodonshare.com/?text=#{URI.encode_www_form_component(params[:title])}&url=#{URI.encode_www_form_component(params[:url])}"
+    when :telegram
+      "https://t.me/share/url?url=#{URI.encode_www_form_component(params[:url])}&text=#{URI.encode_www_form_component(params[:title])}"
+    else
+      raise ArgumentError, "Unsupported platform: #{platform}"
+    end
+  end
+end