OPDS: Add a button to display an entry's content block in the download popup (#7767)

plugins/opds.koplugin/opdsbrowser.lua

@@ -612,6 +612,7 @@ end
 function OPDSBrowser:createNewDownloadDialog(path, buttons)
     self.download_dialog = ButtonDialogTitle:new{
         title = T(_("Download folder:\n%1\n\nDownload file type:"), BD.dirpath(path)),
+        use_info_style = true,
         buttons = buttons
     }
 end
@@ -650,10 +651,10 @@ function OPDSBrowser:showDownloads(item)
         table.insert(buttons, line)
     end
     table.insert(buttons, {})
-    -- Set download folder button.
+    -- Set download folder and book info buttons.
     table.insert(buttons, {
         {
-            text = _("Select another folder"),
+            text = _("Select folder"),
             callback = function()
                 require("ui/downloadmgr"):new{
                     onConfirm = function(path)
@@ -667,7 +668,18 @@ function OPDSBrowser:showDownloads(item)
                     end,
                 }:chooseDir()
             end,
-        }
+        },
+        {
+            text = _("Book information"),
+            enabled = type(item.content) == "string",
+            callback = function()
+                local TextViewer = require("ui/widget/textviewer")
+                UIManager:show(TextViewer:new{
+                    title = item.text,
+                    text = util.htmlToPlainTextIfHtml(item.content),
+                })
+            end,
+        },
     })
 
     self:createNewDownloadDialog(self.getCurrentDownloadDir(), buttons)