Class: EmailReplyTrimmer

Inherits:
Object
  • Object
show all
Defined in:
lib/email_reply_trimmer.rb

Constant Summary collapse

VERSION =
"0.1.12"
DELIMITER =
"d"
EMBEDDED =
"b"
EMPTY =
"e"
EMAIL_HEADER =
"h"
QUOTE =
"q"
SIGNATURE =
"s"
TEXT =
"t"

Class Method Summary collapse

Class Method Details

.extract_embedded_email(text) ⇒ Object



133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
# File 'lib/email_reply_trimmer.rb', line 133

def self.extract_embedded_email(text)
  return if text.nil? || text =~ /\A[[:space:]]*\z/m

  # do some cleanup
  preprocess!(text)

  # from now on, we'll work on a line-by-line basis
  lines = text.split("\n")

  # identify content of each lines
  pattern = lines.map { |l| identify_line_content(l) }.join

  if index = pattern =~ /(?:h[eqd]*?){3,}[tq]/
    embedded = lines[index..-1].join("\n").strip
    before = lines[0...(pattern[0...index] =~ /e*(b[eqd]*|b*[ed]*)$/)].join("\n").strip
    return [embedded, before]
  end
end

.identify_line_content(line) ⇒ Object



19
20
21
22
23
24
25
26
27
# File 'lib/email_reply_trimmer.rb', line 19

def self.identify_line_content(line)
  return EMPTY        if EmptyLineMatcher.match? line
  return DELIMITER    if DelimiterMatcher.match? line
  return SIGNATURE    if SignatureMatcher.match? line
  return EMBEDDED     if EmbeddedEmailMatcher.match? line
  return EMAIL_HEADER if EmailHeaderMatcher.match? line
  return QUOTE        if QuoteMatcher.match? line
  return TEXT
end

.trim(text, split = false) ⇒ Object



29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
# File 'lib/email_reply_trimmer.rb', line 29

def self.trim(text, split = false)
  return if text.nil? || text =~ /\A[[:space:]]*\z/m

  # do some cleanup
  preprocess!(text)

  # from now on, we'll work on a line-by-line basis
  lines = text.split("\n")
  lines_dup = lines.dup

  # identify content of each lines
  pattern = lines.map { |l| identify_line_content(l) }.join

  # remove everything after the first delimiter
  if pattern =~ /d/
    index = pattern =~ /d/
    pattern = pattern[0...index]
    lines = lines[0...index]
  end

  # remove all mobile signatures
  while pattern =~ /s/
    index = pattern =~ /s/
    pattern.slice!(index)
    lines.slice!(index)
  end

  # when the reply is at the end of the email
  if pattern =~ /^(b[^t]+)*b[bqeh]+t[et]*$/
    index = pattern =~ /t[et]*$/
    pattern = ""
    lines = lines[index..-1]
  end

  # if there is an embedded email marker, not followed by a quote
  # then take everything up to that marker
  if pattern =~ /te*b[^q]*$/
    index = pattern =~ /te*b[^q]*$/
    pattern = pattern[0..index]
    lines = lines[0..index]
  end

  # if there is an embedded email marker, followed by a huge quote
  # then take everything up to that marker
  if pattern =~ /te*b[eqbh]*([te]*)$/ && $1.count("t") < 7
    index = pattern =~ /te*b[eqbh]*[te]*$/
    pattern = pattern[0..index]
    lines = lines[0..index]
  end

  # if there is some text before a huge quote ending the email,
  # then remove the quote
  if pattern =~ /te*[qbe]+$/
    index = pattern =~ /te*[qbe]+$/
    pattern = pattern[0..index]
    lines = lines[0..index]
  end

  # if there still are some embedded email markers, just remove them
  while pattern =~ /b/
    index = pattern =~ /b/
    pattern.slice!(index)
    lines.slice!(index)
  end

  # fix email headers when they span over multiple lines
  if pattern =~ /h+[hte]+h+e/
    index = pattern =~ /h+[hte]+h+e/
    size = pattern[/h+[hte]+h+e/].size
    size.times.each { |s| pattern[index + s] = EMAIL_HEADER }
  end

  # if there are at least 3 consecutive email headers,
  # take everything up to these headers
  if pattern =~ /t[eq]*h{3,}/
    index = pattern =~ /t[eq]*h{3,}/
    pattern = pattern[0..index]
    lines = lines[0..index]
  end

  # if there still are some email headers, just remove them
  while pattern =~ /h/
    index = pattern =~ /h/
    pattern.slice!(index)
    lines.slice!(index)
  end

  # remove trailing quotes when there's at least one line of text
  if pattern =~ /t/ && pattern =~ /[eq]+$/
    index = pattern =~ /[eq]+$/
    pattern = pattern[0...index]
    lines = lines[0...index]
  end

  # results
  trimmed = lines.join("\n").strip

  if split
    [trimmed, compute_elided(lines_dup, lines)]
  else
    trimmed
  end
end