-- Run this explicitly through -*- Lua -*-

-- Copyright 2017 Daniel Silverstone <dsilvers@digital-scurf.org>
-- All rights reserved.
--
-- Redistribution and use in source and binary forms, with or without
-- modification, are permitted provided that the following conditions
-- are met:
-- 1. Redistributions of source code must retain the above copyright
--    notice, this list of conditions and the following disclaimer.
-- 2. Redistributions in binary form must reproduce the above copyright
--    notice, this list of conditions and the following disclaimer in the
--    documentation and/or other materials provided with the distribution.
-- 3. Neither the name of the author nor the names of their contributors
--    may be used to endorse or promote products derived from this software
--    without specific prior written permission.
--
-- THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
-- ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-- IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-- ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
-- FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
-- DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
-- OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
-- HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
-- LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
-- OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
-- SUCH DAMAGE.

local infiles = {...}

local stats = require("luacov.stats")

-- Step 1, merge all the coverage files together into a single one...

local merged = {}

function merge_data(fname)
   local subdata = stats.load(fname)
   for fname, fdat in pairs(subdata) do
      if not merged[fname] then
	 merged[fname] = fdat
      else
	 for i = 1, fdat.max do
	    merged[fname][i] = (merged[fname][i] or 0) + (fdat[i] or 0)
	 end
      end
   end
end

local percent = 0
for i = 1, #infiles do
   merge_data(infiles[i])
   local newpercent = math.floor((i*100) / #infiles)
   if (newpercent - percent > 0) or (newpercent == 100) then
      io.stdout:write(("COVERAGE: %3d%% merged.\r"):format(newpercent))
      percent = newpercent
      io.stdout:flush();
   end
end
io.stdout:write("\n");

-- Step 2, write it all out

print("Saving merged stats")
stats.save("luacov.stats.out", merged)