sile 0.15.5

--- SILE document class interface.
-- @interfaces classes

local class = pl.class()
class.type = "class"
class._name = "base"

class._initialized = false
class.deferredInit = {}
class.pageTemplate = { frames = {}, firstContentFrame = nil }
class.defaultFrameset = {}
class.firstContentFrame = "page"
class.options = setmetatable({}, {
   _opts = {},
   __newindex = function (self, key, value)
      local opts = getmetatable(self)._opts
      if type(opts[key]) == "function" then
         opts[key](class, value)
      elseif type(value) == "function" then
         opts[key] = value
      elseif type(key) == "number" then
         return
      else
         SU.error("Attempted to set an undeclared class option '" .. key .. "'")
      end
   end,
   __index = function (self, key)
      if key == "super" then
         return nil
      end
      if type(key) == "number" then
         return nil
      end
      local opt = getmetatable(self)._opts[key]
      if type(opt) == "function" then
         return opt(class)
      elseif opt then
         return opt
      else
         SU.error("Attempted to get an undeclared class option '" .. key .. "'")
      end
   end,
})
class.hooks = {
   newpage = {},
   endpage = {},
   finish = {},
}

class.packages = {}

function class:_init (options)
   SILE.scratch.half_initialized_class = self
   if self == options then
      options = {}
   end
   SILE.languageSupport.loadLanguage("und") -- preload for unlocalized fallbacks
   self:declareOptions()
   self:registerRawHandlers()
   self:declareSettings()
   self:registerCommands()
   self:setOptions(options)
   self:declareFrames(self.defaultFrameset)
   self:registerPostinit(function (self_)
      -- In the event no packages have called \language explicitly or otherwise triggerend the language loader, at this
      -- point we'll have a language *setting* but not actually have loaded the language. We put it off as long as we
      -- could in case the user changed the default document language and we didn't need to load the system default one,
      -- but that time has come at gone at this point. Make sure we've loaded somethnig...
      local lang = SILE.settings:get("document.language")
      SILE.languageSupport.loadLanguage(lang)
      if type(self.firstContentFrame) == "string" then
         self_.pageTemplate.firstContentFrame = self_.pageTemplate.frames[self_.firstContentFrame]
      end
      local frame = self_:initialFrame()
      SILE.typesetter = SILE.typesetters.base(frame)
      SILE.typesetter:registerPageEndHook(function ()
         SU.debug("frames", function ()
            for _, v in pairs(SILE.frames) do
               SILE.outputter:debugFrame(v)
            end
            return "Drew debug outlines around frames"
         end)
      end)
   end)
end

function class:_post_init ()
   SILE.documentState.documentClass = self
   self._initialized = true
   for i, func in ipairs(self.deferredInit) do
      func(self)
      self.deferredInit[i] = nil
   end
   SILE.scratch.half_initialized_class = nil
end

function class:setOptions (options)
   options = options or {}
   -- Classes that add options with dependencies should explicitly handle them, then exempt them from further processing.
   -- The landscape and crop related options are handled explicitly before papersize, then the "rest" of options that are not interdependent.
   self.options.landscape = SU.boolean(options.landscape, false)
   options.landscape = nil
   self.options.papersize = options.papersize or "a4"
   options.papersize = nil
   self.options.bleed = options.bleed or "0"
   options.bleed = nil
   self.options.sheetsize = options.sheetsize or nil
   options.sheetsize = nil
   for option, value in pairs(options) do
      self.options[option] = value
   end
end

function class:declareOption (option, setter)
   rawset(getmetatable(self.options)._opts, option, nil)
   self.options[option] = setter
end

function class:declareOptions ()
   self:declareOption("class", function (_, name)
      if name then
         if self._legacy then
            self._name = name
         elseif name ~= self._name then
            SU.error("Cannot change class name after instantiation, derive a new class instead.")
         end
      end
      return self._name
   end)
   self:declareOption("landscape", function (_, landscape)
      if landscape then
         self.landscape = landscape
      end
      return self.landscape
   end)
   self:declareOption("papersize", function (_, size)
      if size then
         self.papersize = size
         SILE.documentState.paperSize = SILE.papersize(size, self.options.landscape)
         SILE.documentState.orgPaperSize = SILE.documentState.paperSize
         SILE.newFrame({
            id = "page",
            left = 0,
            top = 0,
            right = SILE.documentState.paperSize[1],
            bottom = SILE.documentState.paperSize[2],
         })
      end
      return self.papersize
   end)
   self:declareOption("sheetsize", function (_, size)
      if size then
         self.sheetsize = size
         SILE.documentState.sheetSize = SILE.papersize(size, self.options.landscape)
         if
            SILE.documentState.sheetSize[1] < SILE.documentState.paperSize[1]
            or SILE.documentState.sheetSize[2] < SILE.documentState.paperSize[2]
         then
            SU.error("Sheet size shall not be smaller than the paper size")
         end
         if SILE.documentState.sheetSize[1] < SILE.documentState.paperSize[1] + SILE.documentState.bleed then
            SU.debug("frames", "Sheet size width augmented to take page bleed into account")
            SILE.documentState.sheetSize[1] = SILE.documentState.paperSize[1] + SILE.documentState.bleed
         end
         if SILE.documentState.sheetSize[2] < SILE.documentState.paperSize[2] + SILE.documentState.bleed then
            SU.debug("frames", "Sheet size height augmented to take page bleed into account")
            SILE.documentState.sheetSize[2] = SILE.documentState.paperSize[2] + SILE.documentState.bleed
         end
      else
         return self.sheetsize
      end
   end)
   self:declareOption("bleed", function (_, dimen)
      if dimen then
         self.bleed = dimen
         SILE.documentState.bleed = SU.cast("measurement", dimen):tonumber()
      end
      return self.bleed
   end)
end

function class.declareSettings (_)
   SILE.settings:declare({
      parameter = "current.parindent",
      type = "glue or nil",
      default = nil,
      help = "Glue at start of paragraph",
   })
   SILE.settings:declare({
      parameter = "current.hangIndent",
      type = "measurement or nil",
      default = nil,
      help = "Size of hanging indent",
   })
   SILE.settings:declare({
      parameter = "current.hangAfter",
      type = "integer or nil",
      default = nil,
      help = "Number of lines affected by handIndent",
   })
end

function class:loadPackage (packname, options, reload)
   local pack
   -- Allow loading by injecting whole packages as-is, otherwise try to load it with the usual packages path.
   if type(packname) == "table" then
      pack, packname = packname, packname._name
   elseif type(packname) == "nil" or packname == "nil" or pl.stringx.strip(packname) == "" then
      SU.error(("Attempted to load package with an invalid packname '%s'"):format(packname))
   else
      pack = require(("packages.%s"):format(packname))
      if pack._name ~= packname then
         SU.error(("Loaded module name '%s' does not match requested name '%s'"):format(pack._name, packname))
      end
   end
   SILE.packages[packname] = pack
   if type(pack) == "table" and pack.type == "package" then -- current package api
      if self.packages[packname] then
         -- If the same package name has been loaded before, we might be loading a modified version of the same package or
         -- we might be re-loading the same package, or we might just be doubling up work because somebody called us twice.
         -- The package itself should take care of the difference between load and reload based on the reload flag here,
         -- but in addition to that we also want to avoid creating a new instance. We want to run the intitializer from the
         -- (possibly different) new module, but not create a new instance ID and loose any connections it made.
         -- To do this we add a create function that returns the current instance. This brings along the _initialized flag
         -- and of course anything else already setup and running.
         local current_instance = self.packages[packname]
         pack._create = function ()
            return current_instance
         end
         pack(options, true)
      else
         self.packages[packname] = pack(options, reload)
      end
   else -- legacy package
      self:initPackage(pack, options)
   end
end

function class:reloadPackage (packname, options)
   return self:loadPackage(packname, options, true)
end

function class:initPackage (pack, options)
   SU.deprecated(
      "class:initPackage(options)",
      "package(options)",
      "0.14.0",
      "0.16.0",
      [[
  This package appears to be a legacy format package. It returns a table
  and expects SILE to guess about what to do. New packages inherit
  from the base class and have a constructor function (_init) that
  automatically handles setup.]]
   )
   if type(pack) == "table" then
      if pack.exports then
         pl.tablex.update(self, pack.exports)
      end
      if type(pack.declareSettings) == "function" then
         pack.declareSettings(self)
      end
      if type(pack.registerRawHandlers) == "function" then
         pack.registerRawHandlers(self)
      end
      if type(pack.registerCommands) == "function" then
         pack.registerCommands(self)
      end
      if type(pack.init) == "function" then
         self:registerPostinit(pack.init, options)
      end
   end
end

--- Register a callback function to be executed after the class initialization has completed.
-- Sometimes a class or package may want to run things after the class has been fully initialized. This can be useful
-- for setting document settings after packages and all their dependencies have been loaded. For example a package might
-- want to trigger something to happen after all frames have been defined, but the package itself doesn't know if it is
-- being loaded before or after the document options are processed, frame masters have been setup, etc. Rather than
-- relying on the user to load the package after these events, the package can use this callback to defer the action
-- until those things can be reasonable expected to have completed.
--
-- Functions in the deferred initialization queue are run on a first-set first-run basis.
--
-- Note the typesetter will *not* have been instantiated yet, so is not appropriate to try to output content at this
-- point. Injecting content to be processed at the start of a document should be done with preambles. The inputter
-- *will* be instantiated at this point, so adding a new preamble is viable.
-- If the class has already been initialized the callback function will be run immediately.
-- @tparam function func Callback function accepting up to two arguments.
-- @tparam[opt] table options Additional table passed as a second argument to the callback.
function class:registerPostinit (func, options)
   if self._initialized then
      return func(self, options)
   end
   table.insert(self.deferredInit, function (_)
      func(self, options)
   end)
end

function class:registerHook (category, func)
   for _, func_ in ipairs(self.hooks[category]) do
      if func_ == func then
         return
         --[[ See https://github.com/sile-typesetter/sile/issues/1531
      return SU.warn("Attempted to set the same function hook twice, probably unintended, skipping.")
      -- If the same function signature is already set a package is probably being
      -- re-initialized. Ditch the first instance of the hook so that it runs in
      -- the order of last initialization.
      self.hooks[category][_] = nil
      ]]
      end
   end
   table.insert(self.hooks[category], func)
end

function class:runHooks (category, options)
   for _, func in ipairs(self.hooks[category]) do
      SU.debug("classhooks", "Running hook from", category, options and "with options #" .. #options)
      func(self, options)
   end
end

--- Register a function as a SILE command.
-- Takes any Lua function and registers it for use as a SILE command (which will in turn be used to process any content
-- nodes identified with the command name.
--
-- Note that this should only be used to register commands supplied directly by a document class. A similar method is
-- available for packages, `packages:registerCommand`.
-- @tparam string name Name of cammand to register.
-- @tparam function func Callback function to use as command handler.
-- @tparam[opt] nil|string help User friendly short usage string for use in error messages, documentation, etc.
-- @tparam[opt] nil|string pack Information identifying the module registering the command for use in error and usage
-- messages. Usually auto-detected.
-- @see SILE.packages:registerCommand
function class.registerCommand (_, name, func, help, pack)
   SILE.Commands[name] = func
   if not pack then
      local where = debug.getinfo(2).source
      pack = where:match("(%w+).lua")
   end
   --if not help and not pack:match(".sil") then SU.error("Could not define command '"..name.."' (in package "..pack..") - no help text" ) end
   SILE.Help[name] = {
      description = help,
      where = pack,
   }
end

function class.registerRawHandler (_, format, callback)
   SILE.rawHandlers[format] = callback
end

function class:registerRawHandlers ()
   self:registerRawHandler("text", function (_, content)
      SILE.settings:temporarily(function ()
         SILE.settings:set("typesetter.parseppattern", "\n")
         SILE.settings:set("typesetter.obeyspaces", true)
         SILE.typesetter:typeset(content[1])
      end)
   end)
end

local function packOptions (options)
   local relevant = pl.tablex.copy(options)
   relevant.src = nil
   relevant.format = nil
   relevant.module = nil
   relevant.require = nil
   return relevant
end

function class:registerCommands ()
   local function replaceProcessBy (replacement, tree)
      if type(tree) ~= "table" then
         return tree
      end
      local ret = pl.tablex.deepcopy(tree)
      if tree.command == "process" then
         return replacement
      else
         for i, child in ipairs(tree) do
            ret[i] = replaceProcessBy(replacement, child)
         end
         return ret
      end
   end

   self:registerCommand("define", function (options, content)
      SU.required(options, "command", "defining command")
      if type(content) == "function" then
         -- A macro defined as a function can take no argument, so we register
         -- it as-is.
         self:registerCommand(options["command"], content)
         return
      elseif options.command == "process" then
         SU.warn("Did you mean to re-definine the `\\process` macro? That probably won't go well.")
      end
      self:registerCommand(options["command"], function (_, inner_content)
         SU.debug("macros", "Processing macro \\" .. options["command"])
         local macroArg
         if type(inner_content) == "function" then
            macroArg = inner_content
         elseif type(inner_content) == "table" then
            macroArg = pl.tablex.copy(inner_content)
            macroArg.command = nil
            macroArg.id = nil
         elseif inner_content == nil then
            macroArg = {}
         else
            SU.error(
               "Unhandled content type " .. type(inner_content) .. " passed to macro \\" .. options["command"],
               true
            )
         end
         -- Replace every occurrence of \process in `content` (the macro
         -- body) with `macroArg`, then have SILE go through the new `content`.
         local newContent = replaceProcessBy(macroArg, content)
         SILE.process(newContent)
         SU.debug("macros", "Finished processing \\" .. options["command"])
      end, options.help, SILE.currentlyProcessingFile)
   end, "Define a new macro. \\define[command=example]{ ... \\process }")

   -- A utility function that allows SILE.call() to be used as a noop wrapper.
   self:registerCommand("noop", function (_, content)
      SILE.process(content)
   end)

   -- The document (SIL) or sile (XML) command is always the sigular leaf at the
   -- top level of our AST. The work you might expect to see happen here is
   -- actually handled by SILE.inputter:classInit() before we get here, so these
   -- are just pass through functions. Theoretically, this could be a useful
   -- point to hook into-especially for included documents.
   self:registerCommand("document", function (_, content)
      SILE.process(content)
   end)
   self:registerCommand("sile", function (_, content)
      SILE.process(content)
   end)

   self:registerCommand("comment", function (_, _) end, "Ignores any text within this command's body.")

   self:registerCommand("process", function ()
      SU.error("Encountered unsubstituted \\process.")
   end, "Within a macro definition, processes the contents of the macro body.")

   self:registerCommand("script", function (options, content)
      local packopts = packOptions(options)
      local function _deprecated (original, suggested)
         SU.deprecated(
            "\\script",
            "\\lua or \\use",
            "0.15.0",
            "0.16.0",
            ([[
      The \script function has been deprecated. It was overloaded to mean
      too many different things and more targeted tools were introduced in
      SILE v0.14.0. To load 3rd party modules designed for use with SILE,
      replace \script[src=...] with \use[module=...]. To run arbitrary Lua
      code inline use \lua{}, optionally with a require= parameter to load
      a (non-SILE) Lua module using the Lua module path or src= to load a
      file by file path.

      For this use case consider replacing:

          %s

      with:

          %s
      ]]):format(original, suggested)
         )
      end
      if SU.ast.hasContent(content) then
         _deprecated("\\script{...}", "\\lua{...}")
         return SILE.processString(content[1], options.format or "lua", nil, packopts)
      elseif options.src then
         local module = options.src:gsub("%/", ".")
         local original = (("\\script[src=%s]"):format(options.src))
         local result = SILE.require(options.src)
         local suggested = (result._name and "\\use[module=%s]" or "\\lua[require=%s]"):format(module)
         _deprecated(original, suggested)
         return result
      else
         SU.error("\\script function requires inline content or a src file path")
         return SILE.processString(content[1], options.format or "lua", nil, packopts)
      end
   end, "Runs lua code. The code may be supplied either inline or using src=...")

   self:registerCommand("include", function (options, content)
      local packopts = packOptions(options)
      if SU.ast.hasContent(content) then
         local doc = SU.ast.contentToString(content)
         return SILE.processString(doc, options.format, nil, packopts)
      elseif options.src then
         return SILE.processFile(options.src, options.format, packopts)
      else
         SU.error("\\include function requires inline content or a src file path")
      end
   end, "Includes a content file for processing.")

   self:registerCommand(
      "lua",
      function (options, content)
         local packopts = packOptions(options)
         if SU.ast.hasContent(content) then
            local doc = SU.ast.contentToString(content)
            return SILE.processString(doc, "lua", nil, packopts)
         elseif options.src then
            return SILE.processFile(options.src, "lua", packopts)
         elseif options.require then
            local module = SU.required(options, "require", "lua")
            return require(module)
         else
            SU.error("\\lua function requires inline content or a src file path or a require module name")
         end
      end,
      "Run Lua code. The code may be supplied either inline, using require=... for a Lua module, or using src=... for a file path"
   )

   self:registerCommand("sil", function (options, content)
      local packopts = packOptions(options)
      if SU.ast.hasContent(content) then
         local doc = SU.ast.contentToString(content)
         return SILE.processString(doc, "sil")
      elseif options.src then
         return SILE.processFile(options.src, "sil", packopts)
      else
         SU.error("\\sil function requires inline content or a src file path")
      end
   end, "Process sil content. The content may be supplied either inline or using src=...")

   self:registerCommand("xml", function (options, content)
      local packopts = packOptions(options)
      if SU.ast.hasContent(content) then
         local doc = SU.ast.contentToString(content)
         return SILE.processString(doc, "xml", nil, packopts)
      elseif options.src then
         return SILE.processFile(options.src, "xml", packopts)
      else
         SU.error("\\xml function requires inline content or a src file path")
      end
   end, "Process xml content. The content may be supplied either inline or using src=...")

   self:registerCommand(
      "use",
      function (options, content)
         local packopts = packOptions(options)
         if content[1] and string.len(content[1]) > 0 then
            local doc = SU.ast.contentToString(content)
            SILE.processString(doc, "lua", nil, packopts)
         else
            if options.src then
               SU.warn(
                  "Use of 'src' with \\use is discouraged because some of it's path handling\n  will eventually be deprecated. Use 'module' instead when possible."
               )
               SILE.processFile(options.src, "lua", packopts)
            else
               local module = SU.required(options, "module", "use")
               SILE.use(module, packopts)
            end
         end
      end,
      "Load and initialize a SILE module (can be a package, a shaper, a typesetter, or whatever). Use module=... to specif what to load or include module code inline."
   )

   self:registerCommand("raw", function (options, content)
      local rawtype = SU.required(options, "type", "raw")
      local handler = SILE.rawHandlers[rawtype]
      if not handler then
         SU.error("No inline handler for '" .. rawtype .. "'")
      end
      handler(options, content)
   end, "Invoke a raw passthrough handler")

   self:registerCommand("pagetemplate", function (options, content)
      SILE.typesetter:pushState()
      SILE.documentState.thisPageTemplate = { frames = {} }
      SILE.process(content)
      SILE.documentState.thisPageTemplate.firstContentFrame = SILE.getFrame(options["first-content-frame"])
      SILE.typesetter:initFrame(SILE.documentState.thisPageTemplate.firstContentFrame)
      SILE.typesetter:popState()
   end, "Defines a new page template for the current page and sets the typesetter to use it.")

   self:registerCommand("frame", function (options, _)
      SILE.documentState.thisPageTemplate.frames[options.id] = SILE.newFrame(options)
   end, "Declares (or re-declares) a frame on this page.")

   self:registerCommand("penalty", function (options, _)
      if SU.boolean(options.vertical, false) and not SILE.typesetter:vmode() then
         SILE.typesetter:leaveHmode()
      end
      if SILE.typesetter:vmode() then
         SILE.typesetter:pushVpenalty({ penalty = tonumber(options.penalty) })
      else
         SILE.typesetter:pushPenalty({ penalty = tonumber(options.penalty) })
      end
   end, "Inserts a penalty node. Option is penalty= for the size of the penalty.")

   self:registerCommand("discretionary", function (options, _)
      local discretionary = SILE.types.node.discretionary({})
      if options.prebreak then
         local hbox = SILE.typesetter:makeHbox({ options.prebreak })
         discretionary.prebreak = { hbox }
      end
      if options.postbreak then
         local hbox = SILE.typesetter:makeHbox({ options.postbreak })
         discretionary.postbreak = { hbox }
      end
      if options.replacement then
         local hbox = SILE.typesetter:makeHbox({ options.replacement })
         discretionary.replacement = { hbox }
      end
      table.insert(SILE.typesetter.state.nodes, discretionary)
   end, "Inserts a discretionary node.")

   self:registerCommand("glue", function (options, _)
      local width = SU.cast("length", options.width):absolute()
      SILE.typesetter:pushGlue(width)
   end, "Inserts a glue node. The width option denotes the glue dimension.")

   self:registerCommand("kern", function (options, _)
      local width = SU.cast("length", options.width):absolute()
      SILE.typesetter:pushHorizontal(SILE.types.node.kern(width))
   end, "Inserts a glue node. The width option denotes the glue dimension.")

   self:registerCommand("skip", function (options, _)
      options.discardable = SU.boolean(options.discardable, false)
      options.height = SILE.types.length(options.height):absolute()
      SILE.typesetter:leaveHmode()
      if options.discardable then
         SILE.typesetter:pushVglue(options)
      else
         SILE.typesetter:pushExplicitVglue(options)
      end
   end, "Inserts vertical skip. The height options denotes the skip dimension.")

   self:registerCommand("par", function (_, _)
      SILE.typesetter:endline()
   end, "Ends the current paragraph.")
end

function class:initialFrame ()
   SILE.documentState.thisPageTemplate = pl.tablex.deepcopy(self.pageTemplate)
   SILE.frames = { page = SILE.frames.page }
   for k, v in pairs(SILE.documentState.thisPageTemplate.frames) do
      SILE.frames[k] = v
   end
   if not SILE.documentState.thisPageTemplate.firstContentFrame then
      SILE.documentState.thisPageTemplate.firstContentFrame = SILE.frames[self.firstContentFrame]
   end
   SILE.documentState.thisPageTemplate.firstContentFrame:invalidate()
   return SILE.documentState.thisPageTemplate.firstContentFrame
end

function class:declareFrame (id, spec)
   spec.id = id
   if spec.solve then
      self.pageTemplate.frames[id] = spec
   else
      self.pageTemplate.frames[id] = SILE.newFrame(spec)
   end
   --   next = spec.next,
   --   left = spec.left and fW(spec.left),
   --   right = spec.right and fW(spec.right),
   --   top = spec.top and fH(spec.top),
   --   bottom = spec.bottom and fH(spec.bottom),
   --   height = spec.height and fH(spec.height),
   --   width = spec.width and fH(spec.width),
   --   id = id
   -- })
end

function class:declareFrames (specs)
   if specs then
      for k, v in pairs(specs) do
         self:declareFrame(k, v)
      end
   end
end

-- WARNING: not called as class method
function class.newPar (typesetter)
   local parindent = SILE.settings:get("current.parindent") or SILE.settings:get("document.parindent")
   -- See https://github.com/sile-typesetter/sile/issues/1361
   -- The parindent *cannot* be pushed non-absolutized, as it may be evaluated
   -- outside the (possibly temporary) setting scope where it was used for line
   -- breaking.
   -- Early absolutization can be problematic sometimes, but here we do not
   -- really have the choice.
   -- As of problematic cases, consider a parindent that would be defined in a
   -- frame-related unit (%lw, %fw, etc.). If a frame break occurs and the next
   -- frame has a different width, the parindent won't be re-evaluated in that
   -- new frame context. However, defining a parindent in such a unit is quite
   -- unlikely. And anyway pushback() has plenty of other issues.
   typesetter:pushGlue(parindent:absolute())
   local hangIndent = SILE.settings:get("current.hangIndent")
   if hangIndent then
      SILE.settings:set("linebreak.hangIndent", hangIndent)
   end
   local hangAfter = SILE.settings:get("current.hangAfter")
   if hangAfter then
      SILE.settings:set("linebreak.hangAfter", hangAfter)
   end
end

-- WARNING: not called as class method
function class.endPar (typesetter)
   -- If we're already explicitly out of hmode don't do anything special in the way of skips or indents. Assume the user
   -- has handled that how they want, e.g. with a skip.
   local queue = typesetter.state.outputQueue
   local last_vbox = queue and queue[#queue]
   local last_is_vglue = last_vbox and last_vbox.is_vglue
   local last_is_vpenalty = last_vbox and last_vbox.is_penalty
   if typesetter:vmode() and (last_is_vglue or last_is_vpenalty) then
      return
   end
   SILE.settings:set("current.parindent", nil)
   typesetter:leaveHmode()
   typesetter:pushVglue(SILE.settings:get("document.parskip"))
end

function class:newPage ()
   SILE.outputter:newPage()
   self:runHooks("newpage")
   -- Any other output-routiney things will be done here by inheritors
   return self:initialFrame()
end

function class:endPage ()
   SILE.typesetter.frame:leave(SILE.typesetter)
   self:runHooks("endpage")
   -- I'm trying to call up a new frame here, don't cause a page break in the current one
   -- SILE.typesetter:leaveHmode()
   -- Any other output-routiney things will be done here by inheritors
end

function class:finish ()
   SILE.inputter:postamble()
   SILE.typesetter:endline()
   SILE.call("vfill")
   while not SILE.typesetter:isQueueEmpty() do
      SILE.call("supereject")
      SILE.typesetter:leaveHmode(true)
      SILE.typesetter:buildPage()
      if not SILE.typesetter:isQueueEmpty() then
         SILE.typesetter:initNextFrame()
      end
   end
   SILE.typesetter:runHooks("pageend") -- normally run by the typesetter
   self:endPage()
   if SILE.typesetter and not SILE.typesetter:isQueueEmpty() then
      SU.error("Queues are not empty as expected after ending last page", true)
   end
   SILE.outputter:finish()
   self:runHooks("finish")
end

return class