1from idlelib.configHandler import idleConf
2
3class History:
4
5    def __init__(self, text, output_sep = "\n"):
6        self.text = text
7        self.history = []
8        self.history_prefix = None
9        self.history_pointer = None
10        self.output_sep = output_sep
11        self.cyclic = idleConf.GetOption("main", "History", "cyclic", 1, "bool")
12        text.bind("<<history-previous>>", self.history_prev)
13        text.bind("<<history-next>>", self.history_next)
14
15    def history_next(self, event):
16        self.history_do(0)
17        return "break"
18
19    def history_prev(self, event):
20        self.history_do(1)
21        return "break"
22
23    def _get_source(self, start, end):
24        # Get source code from start index to end index.  Lines in the
25        # text control may be separated by sys.ps2 .
26        lines = self.text.get(start, end).split(self.output_sep)
27        return "\n".join(lines)
28
29    def _put_source(self, where, source):
30        output = self.output_sep.join(source.split("\n"))
31        self.text.insert(where, output)
32
33    def history_do(self, reverse):
34        nhist = len(self.history)
35        pointer = self.history_pointer
36        prefix = self.history_prefix
37        if pointer is not None and prefix is not None:
38            if self.text.compare("insert", "!=", "end-1c") or \
39               self._get_source("iomark", "end-1c") != self.history[pointer]:
40                pointer = prefix = None
41        if pointer is None or prefix is None:
42            prefix = self._get_source("iomark", "end-1c")
43            if reverse:
44                pointer = nhist
45            else:
46                if self.cyclic:
47                    pointer = -1
48                else:
49                    self.text.bell()
50                    return
51        nprefix = len(prefix)
52        while 1:
53            if reverse:
54                pointer = pointer - 1
55            else:
56                pointer = pointer + 1
57            if pointer < 0 or pointer >= nhist:
58                self.text.bell()
59                if not self.cyclic and pointer < 0:
60                    return
61                else:
62                    if self._get_source("iomark", "end-1c") != prefix:
63                        self.text.delete("iomark", "end-1c")
64                        self._put_source("iomark", prefix)
65                    pointer = prefix = None
66                break
67            item = self.history[pointer]
68            if item[:nprefix] == prefix and len(item) > nprefix:
69                self.text.delete("iomark", "end-1c")
70                self._put_source("iomark", item)
71                break
72        self.text.mark_set("insert", "end-1c")
73        self.text.see("insert")
74        self.text.tag_remove("sel", "1.0", "end")
75        self.history_pointer = pointer
76        self.history_prefix = prefix
77
78    def history_store(self, source):
79        source = source.strip()
80        if len(source) > 2:
81            # avoid duplicates
82            try:
83                self.history.remove(source)
84            except ValueError:
85                pass
86            self.history.append(source)
87        self.history_pointer = None
88        self.history_prefix = None
89