1 slot.put_into("title", _"Diff")

2

3 local old_draft_id = param.get("old_draft_id", atom.integer)

4 local new_draft_id = param.get("new_draft_id", atom.integer)

5

6 if not old_draft_id or not new_draft_id then

7 slot.put( _"Please choose two versions of the draft to compare")

8 return

9 end

10

11 if old_draft_id == new_draft_id then

12 slot.put( _"Please choose two different versions of the draft to compare")

13 return

14 end

15

16 if old_draft_id > new_draft_id then

17 local tmp = old_draft_id

18 old_draft_id = new_draft_id

19 new_draft_id = tmp

20 end

21

22 local old_draft = Draft:by_id(old_draft_id)

23 local new_draft = Draft:by_id(new_draft_id)

24

25 local key = multirand.string(26, "123456789bcdfghjklmnpqrstvwxyz");

26

27 local old_draft_filename = encode.file_path(request.get_app_basepath(), 'tmp', "diff-" .. key .. "-old.tmp")

28 local new_draft_filename = encode.file_path(request.get_app_basepath(), 'tmp', "diff-" .. key .. "-new.tmp")

29

30 local old_draft_file = assert(io.open(old_draft_filename, "w"))

31 old_draft_file:write(old_draft.content)

32 old_draft_file:write("\n")

33 old_draft_file:close()

34

35 local new_draft_file = assert(io.open(new_draft_filename, "w"))

36 new_draft_file:write(new_draft.content)

37 new_draft_file:write("\n")

38 new_draft_file:close()

39

40 local output, err, status = os.pfilter(nil, "sh", "-c", "diff -U 100000 '" .. old_draft_filename .. "' '" .. new_draft_filename .. "' | grep -v ^--- | grep -v ^+++ | grep -v ^@")

41

42 os.remove(old_draft_filename)

43 os.remove(new_draft_filename)

44

45 if not status then

46 ui.field.text{ value = _"The drafts do not differ" }

47 else

48 slot.put('<table class="diff">')

49 slot.put('<tr><th width="50%">' .. _"Old draft revision" .. '</th><th width="50%">' .. _"New draft revision" .. '</th></tr>')

50

51 local last_state = "unchanged"

52 local lines = {}

53 local removed_lines = nil

54

55 local function process_line(line)

56 local state = "unchanged"

57 local char = line:sub(1,1)

58 line = line:sub(2)

59 state = "unchanged"

60 if char == "-" then

61 state = "-"

62 elseif char == "+" then

63 state = "+"

64 elseif char == "!" then

65 state = "eof"

66 end

67 if last_state == "unchanged" then

68 if state == "unchanged" then

69 lines[#lines+1] = line

70 elseif (state == "-") or (state == "+") or (state == "eof") then

71 local text = table.concat(lines, "\n")

72 slot.put("<tr><td>", encode.html_newlines(encode.html(text)), "</td><td>", encode.html_newlines(encode.html(text)), "</td></tr>")

73 lines = { line }

74 end

75 elseif last_state == "-" then

76 if state == "-" then

77 lines[#lines+1] = line

78 elseif state == "+" then

79 removed_lines = lines

80 lines = { line }

81 elseif (state == "unchanged") or (state == "eof") then

82 local text = table.concat(lines,"\n")

83 slot.put('<tr><td class="removed">', encode.html_newlines(encode.html(text)), "</td><td></td></tr>")

84 lines = { line }

85 end

86 elseif last_state == "+" then

87 if state == "+" then

88 lines[#lines+1] = line

89 elseif (state == "-") or (state == "unchanged") or (state == "eof") then

90 if removed_lines then

91 local text = table.concat(lines, "\n")

92 local removed_text = table.concat(removed_lines, "\n")

93 slot.put('<tr><td class="removed">', encode.html_newlines(encode.html(removed_text)), '</td><td class="added">', encode.html_newlines(encode.html(text)), "</td></tr>")

94 else

95 local text = table.concat(lines, "\n")

96 slot.put('<tr><td></td><td class="added">', encode.html_newlines(encode.html(text)), "</td></tr>")

97 end

98 removed_lines = nil

99 lines = { line }

100 end

101 end

102 last_state = state

103 end

104

105 output = output .. " "

106 output = output:gsub("[^\n\r]+", function(line)

107 process_line(line)

108 end)

109 process_line("!")

110

111 slot.put("</table>")

112 end

113