#!/usr/bin/env texlua
-------------------------------------------------------------------------------
--         FILE:  mkimport.lua
--        USAGE:  ./mkimport.lua
--  DESCRIPTION:  check luaotfload imports against Context
-- REQUIREMENTS:  luatex, the lualibs package, Context MkIV
--       AUTHOR:  Philipp Gesang (Phg), <phg@phi-gamma.net>
--      VERSION:  42
--      CREATED:  2014-12-08 22:36:15+0100
-------------------------------------------------------------------------------
--

-------------------------------------------------------------------------------
--- PURPOSE
--- 
---  - Facilitate detecting changes in the fontloader source.
---  - Assist in updating source code and (partially) automate importing.
---  - Account for files in the plain fontloader distribution, alert in case of
---    additions or deletions.
---    
-------------------------------------------------------------------------------

kpse.set_program_name "luatex"

local lfs = require "lfs"
local md5 = require "md5"

require "lualibs"

local ioloaddata   = io.loaddata
local iowrite      = io.write
local md5sumhexa   = md5.sumhexa
local stringformat = string.format

-------------------------------------------------------------------------------
-- config
-------------------------------------------------------------------------------

local context_root      = "/home/phg/context/tex/texmf-context"
local our_prefix        = "fontloader"
local fontloader_subdir = "src/fontloader"

local paths = {
  context    = "tex/context/base",
  fontloader = "tex/generic/context/luatex",
}

local subdirs = {
  "runtime",
  "misc"
}

local searchdirs = {
  --- order is important!
  fontloader_subdir,
  context_root
}

local prefixes = {
  context    = nil,
  fontloader = "luatex",
}

-------------------------------------------------------------------------------
-- helpers
-------------------------------------------------------------------------------

local die = function (...)
  io.stderr:write "[\x1b[1;30;41mfatal error\x1b[0m]: "
  io.stderr:write (stringformat (...))
  io.stderr:write "\naborting.\n"
  os.exit (1)
end

local emphasis = function (txt)
  return stringformat("\x1b[1m%s\x1b[0m", txt)
end

local msg = function (...)
  iowrite (stringformat (...))
  iowrite "\n"
end

local separator_string = string.rep ("-", 79)
local separator = function ()
  iowrite (separator_string)
  iowrite "\n"
end

local good_tag   = stringformat("[\x1b[1;30;%dmgood\x1b[0m]   · ", 42)
local bad_tag    = stringformat("[\x1b[1;30;%dmBAD\x1b[0m]    · ", 41)
local alert_tag  = stringformat("[\x1b[1;%dmalert\x1b[0m]  · "   , 36)
local status_tag = stringformat("[\x1b[0;%dmstatus\x1b[0m] · "   , 36)

local good = function (...)
  local msg = (stringformat (...))
  iowrite (good_tag)
  iowrite (msg)
  iowrite "\n"
end

local bad = function (...)
  local msg = (stringformat (...))
  iowrite (bad_tag)
  iowrite (msg)
  iowrite "\n"
end

local attention = function (...)
  local msg = (stringformat (...))
  iowrite (alert_tag)
  iowrite (msg)
  iowrite "\n"
end

local status = function (...)
  local msg = (stringformat (...))
  iowrite (status_tag)
  iowrite (msg)
  iowrite "\n"
end

-------------------------------------------------------------------------------
-- definitions
-------------------------------------------------------------------------------

--- Accounting of upstream files. There are different categories:
---
---   · *essential*: Files required at runtime.
---   · *merged*:    Files merged into the fontloader package.
---   · *ignored*:   Lua files not merged, but part of the format.
---   · *tex*:       TeX code, i.e. format and examples.
---   · *lualibs*:   Files merged, but also provided by the Lualibs package.

local kind_essential = 0
local kind_merged    = 1
local kind_tex       = 2
local kind_ignored   = 3
local kind_lualibs   = 4

local imports = {

  fontloader = {
    { name = "basics-gen"        , ours = nil          , kind = kind_essential },
    { name = "basics-nod"        , ours = nil          , kind = kind_merged    },
    { name = "basics"            , ours = nil          , kind = kind_tex       },
    { name = "fonts-cbk"         , ours = nil          , kind = kind_merged    },
    { name = "fonts-def"         , ours = nil          , kind = kind_merged    },
    { name = "fonts-demo-vf-1"   , ours = nil          , kind = kind_ignored   },
    { name = "fonts-enc"         , ours = nil          , kind = kind_merged    },
    { name = "fonts-ext"         , ours = nil          , kind = kind_merged    },
    { name = "fonts-inj"         , ours = nil          , kind = kind_merged    },
    { name = "fonts-lua"         , ours = nil          , kind = kind_merged    },
    { name = "fonts-merged"      , ours = "fontloader" , kind = kind_essential },
    { name = "fonts-ota"         , ours = nil          , kind = kind_merged    },
    { name = "fonts-otn"         , ours = nil          , kind = kind_merged    },
    { name = "fonts"             , ours = nil          , kind = kind_merged    },
    { name = "fonts"             , ours = nil          , kind = kind_tex       },
    { name = "fonts-syn"         , ours = nil          , kind = kind_ignored   },
    { name = "fonts-tfm"         , ours = nil          , kind = kind_merged    },
    { name = "languages"         , ours = nil          , kind = kind_ignored   },
    { name = "languages"         , ours = nil          , kind = kind_tex       },
    { name = "math"              , ours = nil          , kind = kind_ignored   },
    { name = "math"              , ours = nil          , kind = kind_tex       },
    { name = "mplib"             , ours = nil          , kind = kind_ignored   },
    { name = "mplib"             , ours = nil          , kind = kind_tex       },
    { name = "plain"             , ours = nil          , kind = kind_tex       },
    { name = "preprocessor"      , ours = nil          , kind = kind_ignored   },
    { name = "preprocessor"      , ours = nil          , kind = kind_tex       },
    { name = "preprocessor-test" , ours = nil          , kind = kind_tex       },
    { name = "swiglib"           , ours = nil          , kind = kind_ignored   },
    { name = "swiglib"           , ours = nil          , kind = kind_tex       },
    { name = "swiglib-test"      , ours = nil          , kind = kind_ignored   },
    { name = "swiglib-test"      , ours = nil          , kind = kind_tex       },
    { name = "test"              , ours = nil          , kind = kind_tex       },
  }, --[[ [fontloader] ]]

  context = { --=> all merged
    { name = "data-con"          , ours = "data-con"          , kind = kind_merged    },
    { name = "font-afk"          , ours = "font-afk"          , kind = kind_merged    },
    { name = "font-afm"          , ours = "font-afm"          , kind = kind_merged    },
    { name = "font-cid"          , ours = "font-cid"          , kind = kind_merged    },
    { name = "font-con"          , ours = "font-con"          , kind = kind_merged    },
    { name = "font-def"          , ours = "font-def"          , kind = kind_merged    },
    { name = "font-ini"          , ours = "font-ini"          , kind = kind_merged    },
    { name = "font-map"          , ours = "font-map"          , kind = kind_merged    },
    { name = "font-otb"          , ours = "font-otb"          , kind = kind_merged    },
    { name = "font-otf"          , ours = "font-otf"          , kind = kind_merged    },
    { name = "font-oti"          , ours = "font-oti"          , kind = kind_merged    },
    { name = "font-otp"          , ours = "font-otp"          , kind = kind_merged    },
    { name = "font-tfm"          , ours = "font-tfm"          , kind = kind_merged    },
    { name = "l-boolean"         , ours = "l-boolean"         , kind = kind_lualibs   },
    { name = "l-file"            , ours = "l-file"            , kind = kind_lualibs   },
    { name = "l-function"        , ours = "l-function"        , kind = kind_lualibs   },
    { name = "l-io"              , ours = "l-io"              , kind = kind_lualibs   },
    { name = "l-lpeg"            , ours = "l-lpeg"            , kind = kind_lualibs   },
    { name = "l-lua"             , ours = "l-lua"             , kind = kind_lualibs   },
    { name = "l-math"            , ours = "l-math"            , kind = kind_lualibs   },
    { name = "l-string"          , ours = "l-string"          , kind = kind_lualibs   },
    { name = "l-table"           , ours = "l-table"           , kind = kind_lualibs   },
    { name = "util-str"          , ours = "util-str"          , kind = kind_lualibs   },
  }, --[[ [context] ]]
} --[[ [imports] ]]

local hash_file = function (fname)
  if not lfs.isfile (fname) then
    die ("cannot find %s.", fname)
  end
  local raw = ioloaddata (fname)
  if not raw then
    die ("cannot read from %s.", fname)
  end
  return md5sumhexa (raw)
end

local derive_category_path = function (cat)
  local subpath  = paths[cat] or die ("category " .. cat .. " unknown")
  local location = file.join (context_root, subpath)
  if not lfs.isdir (location) then
    die ("invalid base path defined for category "
         .. cat .. " at " .. location)
  end
  return location
end

local derive_suffix = function (kind)
  if kind == kind_tex then return ".tex" end
  return ".lua"
end

local derive_fullname = function (cat, name, kind)
  local tmp = prefixes[cat]
  tmp = tmp and tmp .. "-" .. name or name
  return tmp .. derive_suffix (kind)
end

local derive_ourname = function (name, kind)
  local suffix = derive_suffix (kind)
  local subdir = kind == kind_essential and "runtime" or "misc"
  return subdir, our_prefix .. "-" .. name .. suffix
end

local is_readable = function (f)
  local fh = io.open (f, "r")
  if fh then
    fh:close()
    return true
  end
  return false
end

local summarize_news = function (status)
  local ni = #status.import
  local nc = #status.create
  local ng = #status.good
  local nm = #status.missing

  separator ()
  msg ("Summary: Inspected %d files.", ni + nc + ng + nm)
  separator ()
  if ng > 0 then good      ("%d are up to date", ng) end
  if ni > 0 then attention ("%d changed"       , ni) end
  if nc > 0 then attention ("%d new"           , nc) end
  if nm > 0 then bad       ("%d missing"       , nm) end
  separator ()

  if nm == 0 and nc == 0 and ni == 0 then
    return 0
  end

  return -1
end

local news = function ()
  local status = {
    import  = { },
    good    = { },
    create  = { },
    missing = { },
  }

  for cat, entries in next, imports do
    local location = derive_category_path (cat)
    local nfiles = #entries

    for i = 1, nfiles do
      local def  = entries[i]
      local name = def.name
      local ours = def.ours
      local kind = def.kind
      local fullname = derive_fullname (cat, name, kind)
      local fullpath = file.join (location, fullname)
      local subdir, ourname  = derive_ourname (ours or name, kind)
      local ourpath  = file.join (fontloader_subdir, subdir, ourname) -- relative
      local imported = false

      if not is_readable (fullpath) then
        bad ("source for file %s not found at %s",
             emphasis (ourname),
             emphasis (fullpath))
        status.missing[#status.missing + 1] = ourname
      else
        --- Source file exists and is readable.
        if not lfs.isdir (fontloader_subdir) then
          die ("path for fontloader tree ("
              .. fontloader_subdir .. ") is not a directory")
        end
        if is_readable (ourpath) then imported = true end
        local src_hash = hash_file (fullpath)
        local dst_hash = imported and hash_file (ourpath)
        local same     = src_hash == dst_hash -- same!

        if same then
          good ("file %s unchanged", emphasis (ourname))
          status.good[#status.good + 1] = ourname
        elseif not dst_hash then
          attention ("new file %s requires import from %s",
                    emphasis (ourname),
                    emphasis (fullpath))
          status.create[#status.create + 1] = ourname
        else --- src and dst exist but differ
          attention ("file %s requires import", emphasis (ourname))
          status.import[#status.import + 1] = ourname
        end
      end

    end
  end

  return summarize_news (status)
end --[[ [local news = function ()] ]]

local get_file_definition = function (name, ourname, kind)
  kind = kind or "lua"
  for cat, defs in next, imports do
    local fullname = derive_fullname (cat, name, kind)
    local ndefs = #defs
    for i = 1, ndefs do
      local def = defs[i]
      local dname = def.name
      local dours = def.ours or def.name
      local dkind = def.kind

      --- test properties
      local subdir, derived = derive_ourname (dours, dkind)
      if                             derived == ourname  then return def, cat end
      if derive_fullname (cat, dname, dkind) == fullname then return def, cat end
      if                               dours == ourname  then return def, cat end
      if                               dname == fullname then return def, cat end
    end
  end
  --- search unsuccessful
end --[[ [local get_file_definition = function (name, ourname, kind)] ]]

local import_imported = 0
local import_skipped  = 1
local import_failed   = 2
local import_created  = 3

local import_status = {
  [import_imported] = "imported",
  [import_skipped ] = "skipped",
  [import_failed  ] = "failed",
  [import_created ] = "created",
}

local summarize_status = function (counters)
  local imported = counters[import_imported] or 0
  local skipped  = counters[import_skipped ] or 0
  local created  = counters[import_created ] or 0
  local failed   = counters[import_failed  ] or 0
  local sum = imported + skipped + created + failed
  if sum < 1 then die ("garbage total of imported files: %s", sum) end
  separator ()
  status (" RESULT: %d files processed", sum)
  separator ()
  if created  > 0 then status ("created:  %d (%d %%)", created , created  * 100 / sum) end
  if imported > 0 then status ("imported: %d (%d %%)", imported, imported * 100 / sum) end
  if skipped  > 0 then status ("skipped:  %d (%d %%)", skipped , skipped  * 100 / sum) end
  separator ()
end

local import_file = function (name, kind, def, cat)
  local expected_ourname = derive_ourname (name)
  if not def or not cat then
    def, cat = get_file_definition (name, expected_ourname, kind)
  end

  if not def then die ("unable to find a definition matching " .. name) end
  if not cat then die ("missing category for file " .. name .. " -- WTF‽") end

  local dname    = def.name
  local dours    = def.ours or dname
  local dkind    = def.kind
  local srcdir   = derive_category_path (cat)
  local fullname = derive_fullname (cat, dname, kind)
  local subdir, ourname = derive_ourname (dours, kind)
  local ourpath  = file.join (fontloader_subdir, subdir)
  local src      = file.join (srcdir, fullname)
  local dst      = file.join (ourpath, ourname)
  local new      = not lfs.isfile (dst)
  if not new and hash_file (src) == hash_file (dst) then
    status ("file %s is unchanged, skipping", fullname)
    return import_skipped
  end
  if not (lfs.isdir (ourpath) or not lfs.mkdirs (ourpath)) then
    die ("failed to create directory %s for file %s",
         ourpath, ourname)
  end
  status ("importing file %s", fullname)
  file.copy (src, dst)
  if hash_file (src) == hash_file (dst) then
    if new then return import_created end
    return import_imported end
  return import_failed
end --[[ [local import_file = function (name, kind)] ]]

local import = function (arg)
  if #arg > 1 then
    local name = arg[2] or die ("invalid filename " .. tostring (arg[2]))
    local stat = import_file (name)
    if stat == import_failed then
      die ("failed to import file " .. name)
    end
    status ("import status for file %s: %s", name, import_status[stat])
  end
  --- Multiple files
  local statcount = { } -- import status codes -> size_t
  for cat, defs in next, imports do
    local ndefs = #defs
    for i = 1, ndefs do
      local def  = defs[i]
      local stat = import_file (def.name, def.kind, def, cat)
      if stat == import_failed then
        die (stringformat ("import failed at file %d of %d (%s)",
                           i, ndefs, def.name))
      end
      statcount[stat] = statcount[stat] or 0
      statcount[stat] = statcount[stat] + 1
    end
  end
  summarize_status (statcount)
  return 0
end --[[ [local import = function (arg)] ]]

local search_paths = function (target)
  for i = 1, #searchdirs do
    local root  = searchdirs[i]
    for j = 1, #subdirs do
      local dir  = file.join (searchdirs[i], subdirs[j])
      local file = file.join (dir, target)
      if lfs.isfile (file) then return file end
    end
  end
  return false
end

local search_defs = function (target)
  for cat, defs in next, imports do
    local ndefs = #defs
    for i = 1, ndefs do
      local def = defs[i]

      local dname = def.name
      if target == dname then
        local found = search_paths (target .. derive_suffix (def.kind))
        if found then return found end
      end

      local dfull = dname .. derive_suffix (def.kind)
      if target == dfull then
        local found = search_paths (dfull)
        if found then return found end
      end

      local dours = def.ours
      if dours then

        local _, ourname = derive_ourname (dours, kind)
        if target == dours then
          local found = search_paths (ourname)
          if found then return found end
        end

        if target == ourname then
          local found = search_paths (ourname)
          if found then return found end
        end
      end

    end
  end
  return false
end

local search = function (arg)
  local target = arg[2]
  if not target then die "no filename given" end

  local look_for
  --- pick a file
  if lfs.isfile (target) then --- absolute path given
    look_for = target
    goto found
  else

    --- search as file name in local tree
    look_for = search_paths (target)
    if look_for then goto found end

    --- seach the definitions
    look_for = search_defs (target)
    if look_for then goto found end

  end

::fail::
  if not look_for then return end

::found::
  status ("found file %s at %s", target, look_for)
  return look_for
end

local tell = function (target)
  local location = search (target)
  if not location then
    die ("file %s not found in any of the search locations", target)
  end
end

local help = function ()
  iowrite "usage: mkinfo  <command> [<args>]\n"
  iowrite "\n"
  iowrite "Where <command> is one of\n"
  iowrite "   help      Print this help message\n"
  iowrite "   tell      Display information about a file’s integration\n"
  iowrite "   news      Check Context for updated files\n"
  iowrite "   import    Update with files from Context\n"
  iowrite "\n"
end

local job_kind = table.mirrored {
  news   = news,
  import = import,
  tell   = tell,
  help   = help,
}

-------------------------------------------------------------------------------
-- functionality
-------------------------------------------------------------------------------

--- job_kind -> bool
local check_job = function (j)
  return job_kind[j] or die ("invalid job type “%s”.", j)
end

-------------------------------------------------------------------------------
-- entry point
-------------------------------------------------------------------------------

local main = function ()
  local job = arg[1] or "help"
  local runner = check_job (job)
  return runner(arg)
end

os.exit (main ())

--- vim:ft=lua:ts=2:et:sw=2