src/core/WordList.cpp

   1 #include "WordList.h"
   2
   3 namespace freeRecite {
   4
   5 WordList::WordList(unsigned init__Size)
   6   :__size(init__Size),first(0),last(0)
   7 {
   8   for(unsigned i = 0; i < __size; ++i) {
   9     if(i == 0) {
  10       first = new NodeWord(0);
  11       last = first;
  12       for(int i = 1; i < 4; ++i)
  13         pos[i] = first;
  14     }else {
  15       last->next = new NodeWord(i);
  16       last = last->next;
  17
  18       if( i == 1 )
  19         pos[1] = pos[1]->next;
  20       if( i > 0 && i <= 3 )
  21         pos[2] = pos[2]->next;
  22       if( i > 0 && i <= 10)
  23         pos[3] = pos[3]->next;
  24     }
  25   }
  26 }
  27
  28 WordList::~WordList()
  29 {
  30   pos[0] = first;
  31   while(first != 0) {
  32     first = first->next;
  33     delete pos[0];
  34     pos[0] = 0;
  35   }
  36 }
  37
  38 int WordList::scan() {
  39   if(first->status == 0) {
  40     lose();
  41     return 1;
  42   }else
  43     return pass();
  44 }
  45
  46 int WordList::pass()
  47 {
  48   int status = first->status;
  49   if( status > 0 && status < 4) //You should review it! status = 1,2,3
  50     moveToPos(status);
  51   else if(status == 4) //Put the word to the last to test whether you remember it.
  52     moveToLast();
  53   else //You have remembered it! status = 0,5
  54     pop();
  55   return status;
  56 } //end of function WordList::pass().
  57
  58 void WordList::lose()
  59 {
  60   first->status = 1;
  61 }
  62
  63 void WordList::moveToPos(unsigned i) {
  64   if(pos[i] == last){
  65     moveToLast();
  66   }else {
  67     ++(first->status);
  68     //pos[0] is a tempory variable.
  69     pos[0] = pos[i]->next;
  70     pos[i]->next = first;
  71     first = first->next;
  72     pos[i]->next->next = pos[0];
  73     advancePos(i);
  74   }
  75 }
  76
  77 void WordList::moveToLast() {
  78   ++(first->status);
  79   last->next = first;
  80   last = last->next;
  81   first = first->next;
  82   last->next = 0;
  83   advancePos();;
  84 }
  85
  86 void WordList::pop() {
  87   pos[0] = first;
  88   if(first == last) {
  89     first = 0;
  90     last = 0;
  91     __size = 0;
  92     delete pos[0];
  93     for(int i = 0; i < 4; ++i)
  94       pos[i] = 0;
  95   }else {
  96     first = first->next;
  97     delete pos[0];
  98     --__size;
  99     advancePos();;
 100   }
 101 }
 102
 103 void WordList::add(unsigned size) {
 104   NodeWord *tmp = new NodeWord(size - 1);
 105   last->next = tmp;
 106   last = last->next;
 107   ++__size;
 108 }
 109
 110 void WordList::remove(unsigned size) {
 111   NodeWord *tmp = first;
 112   NodeWord *max = first;
 113   for(int i = 0; i < __size; ++i) {
 114     tmp = tmp->next;
 115     if(max->index < tmp->index)
 116       max = tmp;
 117   }
 118   //Because the user should always call it after remove
 119   //the word from the contain, it subtract 2 here.
 120   if( max->index == (size - 2) ){
 121     max->index = first->index;
 122     pop();
 123   }
 124 }
 125
 126 void WordList::advancePos(unsigned status) {
 127   switch(status) {
 128   case 0:  case 3:
 129     if(pos[3] != last)
 130       pos[3] = pos[3]->next;
 131   case 2:
 132     if(pos[2] != last)
 133       pos[2] = pos[2]->next;
 134   case 1:
 135     if(pos[1] != last)
 136       pos[1] = pos[1]->next;
 137   }
 138 }
 139
 140 } //Namespace freeRecite end.
 141