#!/usr/bin/env lua

local luacov = require("luacov.stats")

local data, most_hits = luacov.load()

if not data then
   print("Could not load stats file "..luacov.statsfile..".")
   print("Run your Lua program with -lluacov and then rerun luacov.")
   os.exit(1)
end

local report = io.open("luacov.report.out", "w")

-- only report on files specified on the command line
local patterns = {}
local exclude_patterns = {}
local exclude_next = false
for i = 1, #arg do
   if arg[i] == "-X" then
      exclude_next = true
   else
      if exclude_next then
         exclude_patterns[#exclude_patterns+1] = arg[i]
         exclude_next = false
      else
         patterns[#patterns+1] = arg[i]
      end
   end
end

local names = {}
for filename, _ in pairs(data) do
   if not patterns[1] then
      table.insert(names, filename)
   else
      local path = filename:gsub("/", "."):gsub("%.lua$", "")
      local include = false
      for _, p in ipairs(patterns) do
         if path:match(p) then
            include = true
            break
         end
      end
      if include then
         for _, p in ipairs(exclude_patterns) do
	    if path:match(p) then
	       include = false
	       break
	    end
	 end
      end
      if include then
         table.insert(names, filename)
      end
   end
end

table.sort(names)

local most_hits_length = ("%d"):format(most_hits):len()
local empty_format = (" "):rep(most_hits_length+1)
local false_negative_format = ("!%% %dd"):format(most_hits_length)
local zero_format = ("*"):rep(most_hits_length).."0"
local count_format = ("%% %dd"):format(most_hits_length+1)

local exclusions =
{
   { false, "^#!" },     -- Unix hash-bang magic line
   { true, "" },         -- Empty line
   { true, "}" },        -- Just a close-brace
   { true, "end,?" },    -- Single "end"
   { true, "else" },     -- Single "else"
   { true, "repeat" },   -- Single "repeat"
   { true, "do" },       -- Single "do"
   { true, "local%s+[%w_,%s]+" }, -- "local var1, ..., varN"
   { true, "local%s+[%w_,%s]+%s*=" }, -- "local var1, ..., varN ="
   { true, "local%s+function%s*%([%w_,%.%s]*%)" }, -- "local function(arg1, ..., argN)"
   { true, "local%s+function%s+[%w_]*%s*%([%w_,%.%s]*%)" }, -- "local function f (arg1, ..., argN)"
}

local function excluded(line)
   for _, e in ipairs(exclusions) do
      if e[1] then
         if line:match("^%s*"..e[2].."%s*$") or line:match("^%s*"..e[2].."%s*%-%-") then return true end
      else
         if line:match(e[2]) then return true end
      end
   end
   return false
end

for _, filename in ipairs(names) do
   local filedata = data[filename]
   local file = io.open(filename, "r")
   if file then
      report:write("\n")
      report:write("==============================================================================\n")
      report:write(filename, "\n")
      report:write("==============================================================================\n")
      local line_nr = 1
      block_comment, equals = false, ""
      while true do
         local line = file:read("*l")
         if not line then break end
         local true_line = line
         
         local new_block_comment = false
         if not block_comment then
            local l, equals = line:match("^(.*)%-%-%[(=*)%[")
            if l then
               line = l
               new_block_comment = true
            end
         else
            local l = line:match("%]"..equals.."%](.*)$")
            if l then
               line = l
               block_comment = false
            end         
         end
         
         local hits = filedata[line_nr] or 0
         if block_comment or excluded(line) then
            if hits > 0 then
               report:write(false_negative_format:format(hits))
            else
               report:write(empty_format)
            end
         else
            if hits == 0 then
               report:write(zero_format)            
            else
               report:write(count_format:format(hits))
            end
         end
         report:write("\t", true_line, "\n")
         if new_block_comment then block_comment = true end
         line_nr = line_nr + 1
      end
   end
end