scrapelib and dump utility

dump.lua

@@ -0,0 +1,2 @@
+local s = require('scrapelib')(arg[1]).Data
+require('pl.pretty').dump(s)

scrapelib.lua

@@ -0,0 +1,133 @@
+local sub = string.sub
+
+local function ref(data, start, ...)
+  local x = start
+  for i = 1, select('#', ...) do
+    local ty = sub(x, 1, 1)
+    assert(ty == 't' or ty == 'f' or ty == 'u')
+    x = data[tonumber(sub(x, 2))][select(i, ...)]
+  end
+  return x
+end
+
+local function tpairs(data, x)
+  assert(type(x) == 'string')
+  local tx = sub(x, 1, 1)
+  assert(tx == 't' or tx == 'f' or tx == 'u')
+  return pairs(data[tonumber(sub(x, 2))])
+end
+
+local function resolve(data, top, depth)
+  depth = depth or math.huge
+  if top == nil then
+    return nil
+  end
+  local refs = {}
+  local function fun(x, lvl)
+    if lvl >= depth then
+      return x
+    end
+    assert(type(x) == 'string', tostring(x) .. ' is not a string')
+    local rx = refs[x]
+    if rx then
+      assert(type(rx) == 'table', 'unsupported loop in structure: ' .. x)
+      return rx
+    end
+    local tx = sub(x, 1, 1)
+    if tx == 'n' then
+      return tonumber(sub(x, 2))
+    elseif tx == 's' then
+      return sub(x, 2)
+    elseif tx == 'b' then
+      return x == 'btrue'
+    elseif tx == 'e' then
+      return '<function environment>'
+    elseif tx == 'm' then
+      return '<metatable>'
+    elseif tx == 'f' or tx == 'u' then
+      refs[x] = true
+      local ret = fun('t' .. sub(x, 2), lvl + 1)
+      refs[x] = ret
+      return ret
+    elseif tx == 't' then
+      refs[x] = true
+      local t = {}
+      for k, v in tpairs(data, x) do
+        t[fun(k, lvl + 1)] = fun(v, lvl + 1)
+      end
+      refs[x] = t
+      return t
+    else
+      error('invalid type on ' .. x)
+    end
+  end
+  return fun(top, 0)
+end
+
+local function names(data, rend)
+  local result = {}
+  local refs = {}
+  local stack = { { '_G', rend } }
+  while #stack > 0 do
+    local str, r = unpack(table.remove(stack))
+    refs[r] = true
+    for k, v in data:tpairs(r) do
+      local tk = sub(k, 1, 1)
+      local s = str
+      if tk == 'm' then
+        s = 'getmetatable(' .. s .. ')'
+      elseif tk == 'e' then
+        s = 'getfenv(' .. s .. ')'
+      elseif tk == 'n' or tk == 'b' then
+        s = s .. '[' .. sub(k, 2) .. ']'
+      elseif tk == 's' then
+        s = s .. '.' .. sub(k, 2)
+      elseif tk == 't' or tk == 'f' or tk == 'u' then
+        print('ignoring table key ' .. k)
+      else
+        error('invalid key ' .. k)
+      end
+      if v == rend then
+        table.insert(result, s)
+      elseif not refs[v] then
+        local tv = sub(v, 1, 1)
+        if tv == 't' or tv == 'u' or tv == 'f' then
+          table.insert(stack, { s, v })
+        end
+      end
+    end
+  end
+  return result
+end
+
+local function global(data, ...)
+  return ref(data, 't1', ...)
+end
+
+local function capsule(data, ...)
+  return global(data, 'sSimpleCheckout', 'sOnLoad', 'e', ...)
+end
+
+local dataMT = {
+  __index = {
+    capsule = capsule,
+    global = global,
+    names = names,
+    ref = ref,
+    resolve = resolve,
+    tpairs = tpairs,
+  },
+  __metatable = 'WowlessSaverData',
+  __newindex = function()
+    error('cannot modify a scrape table')
+  end,
+}
+
+return function(filename)
+  local fenv = {}
+  setfenv(loadfile(filename), fenv)()
+  local str = require('libdeflate'):DecompressDeflate(fenv.TheFlatDumper)
+  local ret = loadstring('return ' .. str)()
+  setmetatable(ret.Data, dataMT)
+  return ret
+end