local Tester = torch.class('torch.Tester')

function Tester:__init()
   self.errors = {}
   self.tests = {}
   self.testnames = {}
   self.curtestname = ''
end


function Tester:assert_sub (condition, message)
   if not condition then
      local ss = debug.traceback('tester',2)
      --print(ss)
      ss = ss:match('[^\n]+\n[^\n]+\n([^\n]+\n[^\n]+)\n')
      self.errors[#self.errors+1] = self.curtestname .. '\n' .. message .. '\n' .. ss .. '\n'
   end
end
function Tester:assert (condition, message)
   self:assert_sub(condition,string.format('%s\n%s  condition=%s',message,' BOOL violation ', tostring(condition)))
end
function Tester:assertlt (val, condition, message)
   self:assert_sub(val<condition,string.format('%s\n%s  val=%s, condition=%s',message,' LT(<) violation ', tostring(val), tostring(condition)))
end
function Tester:assertgt (val, condition, message)
   self:assert_sub(val>condition,string.format('%s\n%s  val=%s, condition=%s',message,' GT(>) violation ', tostring(val), tostring(condition)))
end
function Tester:assertle (val, condition, message)
   self:assert_sub(val<=condition,string.format('%s\n%s  val=%s, condition=%s',message,' LE(<=) violation ', tostring(val), tostring(condition)))
end
function Tester:assertge (val, condition, message)
   self:assert_sub(val>=condition,string.format('%s\n%s  val=%s, condition=%s',message,' GE(>=) violation ', tostring(val), tostring(condition)))
end
function Tester:asserteq (val, condition, message)
   self:assert_sub(val==condition,string.format('%s\n%s  val=%s, condition=%s',message,' EQ(==) violation ', tostring(val), tostring(condition)))
end
function Tester:assertne (val, condition, message)
   self:assert_sub(val~=condition,string.format('%s\n%s  val=%s, condition=%s',message,' NE(~=) violation ', tostring(val), tostring(condition)))
end
function Tester:assertTensorEq(ta, tb, condition, message)
   local diff = ta-tb
   local err = diff:abs():maxall()
   self:assert_sub(err<condition,string.format('%s\n%s  val=%s, condition=%s',message,' TensorEQ(~=) violation ', tostring(err), tostring(condition)))
end

function Tester:pcall(f)
   local nerr = #self.errors
   local res = f()
--    local stat, result = pcall(f)
--    if not stat then
--       result = result .. debug.traceback()
--    end
--    return stat, result, stat and (nerr == #self.errors)
   return true, res, nerr == #self.errors
end

function Tester:report()
   print('Completed ' .. #self.tests .. ' tests with ' .. #self.errors .. ' errors')
   print()
   print(string.rep('-',80))
   for i,v in ipairs(self.errors) do
      print(v)
      print(string.rep('-',80))
   end
end

function Tester:run()
   print('Running ' .. #self.tests .. ' tests')
   local statstr = string.rep('_',#self.tests)
   local pstr = ''
   io.write(statstr .. '\r')
   for i,v in ipairs(self.tests) do
      self.curtestname = self.testnames[i]
      
      --clear
      io.write('\r' .. string.rep(' ', pstr:len()))
      io.flush()
      --write
      pstr = statstr:sub(1,i-1) .. '|' .. statstr:sub(i+1) .. '  ==> ' .. self.curtestname
      io.write('\r' .. pstr)
      io.flush()
      
      local stat, message, pass = self:pcall(v)
      
      if pass then
	 --io.write(string.format('\b_'))
	 statstr = statstr:sub(1,i-1) .. '_' .. statstr:sub(i+1)
      else
	 statstr = statstr:sub(1,i-1) .. '*' .. statstr:sub(i+1)
	 --io.write(string.format('\b*'))
      end
      
      if not stat then
	 print()
	 print('Function call failed: Test No ' .. i .. ' ' .. self.testnames[i])
	 print(message)
      end
      collectgarbage()
   end
   --clear
   io.write('\r' .. string.rep(' ', pstr:len()))
   io.flush()
   -- write finish
   pstr = statstr .. '  ==> Done '
   io.write('\r' .. pstr)
   io.flush()
   print()
   print()
   self:report()
end

function Tester:add(f,name)
   name = name or 'unknown'
   if type(f) == "table" then
      for i,v in pairs(f) do
	 self:add(v,i)
      end
   elseif type(f) == "function" then
      self.tests[#self.tests+1] = f
      self.testnames[#self.tests] = name
   else
      error('Tester:add(f) expects a function or a table of functions')
   end
end