scintilla/RunStyles.cxx

   1 /** @file RunStyles.cxx
   2  ** Data structure used to store sparse styles.
   3  **/
   4 // Copyright 1998-2007 by Neil Hodgson <neilh@scintilla.org>
   5 // The License.txt file describes the conditions under which this software may be distributed.
   6
   7 #include <stdio.h>
   8 #include <string.h>
   9 #include <stdlib.h>
  10 #include <stdarg.h>
  11
  12 #include "Platform.h"
  13
  14 #include "Scintilla.h"
  15 #include "SplitVector.h"
  16 #include "Partitioning.h"
  17 #include "RunStyles.h"
  18
  19 #ifdef SCI_NAMESPACE
  20 using namespace Scintilla;
  21 #endif
  22
  23 // Find the first run at a position
  24 int RunStyles::RunFromPosition(int position) {
  25         int run = starts->PartitionFromPosition(position);
  26         // Go to first element with this position
  27         while ((run > 0) && (position == starts->PositionFromPartition(run-1))) {
  28                 run--;
  29         }
  30         return run;
  31 }
  32
  33 // If there is no run boundary at position, insert one continuing style.
  34 int RunStyles::SplitRun(int position) {
  35         int run = RunFromPosition(position);
  36         int posRun = starts->PositionFromPartition(run);
  37         if (posRun < position) {
  38                 int runStyle = ValueAt(position);
  39                 run++;
  40                 starts->InsertPartition(run, position);
  41                 styles->InsertValue(run, 1, runStyle);
  42         }
  43         return run;
  44 }
  45
  46 void RunStyles::RemoveRun(int run) {
  47         starts->RemovePartition(run);
  48         styles->DeleteRange(run, 1);
  49 }
  50
  51 void RunStyles::RemoveRunIfEmpty(int run) {
  52         if ((run < starts->Partitions()) && (starts->Partitions() > 1)) {
  53                 if (starts->PositionFromPartition(run) == starts->PositionFromPartition(run+1)) {
  54                         RemoveRun(run);
  55                 }
  56         }
  57 }
  58
  59 void RunStyles::RemoveRunIfSameAsPrevious(int run) {
  60         if ((run > 0) && (run < starts->Partitions())) {
  61                 if (styles->ValueAt(run-1) == styles->ValueAt(run)) {
  62                         RemoveRun(run);
  63                 }
  64         }
  65 }
  66
  67 RunStyles::RunStyles() {
  68         starts = new Partitioning(8);
  69         styles = new SplitVector<int>();
  70         styles->InsertValue(0, 2, 0);
  71 }
  72
  73 RunStyles::~RunStyles() {
  74         delete starts;
  75         starts = NULL;
  76         delete styles;
  77         styles = NULL;
  78 }
  79
  80 int RunStyles::Length() const {
  81         return starts->PositionFromPartition(starts->Partitions());
  82 }
  83
  84 int RunStyles::ValueAt(int position) const {
  85         return styles->ValueAt(starts->PartitionFromPosition(position));
  86 }
  87
  88 int RunStyles::FindNextChange(int position, int end) {
  89         int run = starts->PartitionFromPosition(position);
  90         if (run < starts->Partitions()) {
  91                 int runChange = starts->PositionFromPartition(run);
  92                 if (runChange > position)
  93                         return runChange;
  94                 int nextChange = starts->PositionFromPartition(run + 1);
  95                 if (nextChange > position) {
  96                         return nextChange;
  97                 } else if (position < end) {
  98                         return end;
  99                 } else {
 100                         return end + 1;
 101                 }
 102         } else {
 103                 return end + 1;
 104         }
 105 }
 106
 107 int RunStyles::StartRun(int position) {
 108         return starts->PositionFromPartition(starts->PartitionFromPosition(position));
 109 }
 110
 111 int RunStyles::EndRun(int position) {
 112         return starts->PositionFromPartition(starts->PartitionFromPosition(position) + 1);
 113 }
 114
 115 bool RunStyles::FillRange(int &position, int value, int &fillLength) {
 116         int end = position + fillLength;
 117         int runEnd = RunFromPosition(end);
 118         if (styles->ValueAt(runEnd) == value) {
 119                 // End already has value so trim range.
 120                 end = starts->PositionFromPartition(runEnd);
 121                 if (position >= end) {
 122                         // Whole range is already same as value so no action
 123                         return false;
 124                 }
 125                 fillLength = end - position;
 126         } else {
 127                 runEnd = SplitRun(end);
 128         }
 129         int runStart = RunFromPosition(position);
 130         if (styles->ValueAt(runStart) == value) {
 131                 // Start is in expected value so trim range.
 132                 runStart++;
 133                 position = starts->PositionFromPartition(runStart);
 134                 fillLength = end - position;
 135         } else {
 136                 if (starts->PositionFromPartition(runStart) < position) {
 137                         runStart = SplitRun(position);
 138                         runEnd++;
 139                 }
 140         }
 141         if (runStart < runEnd) {
 142                 styles->SetValueAt(runStart, value);
 143                 // Remove each old run over the range
 144                 for (int run=runStart+1; run<runEnd; run++) {
 145                         RemoveRun(runStart+1);
 146                 }
 147                 runEnd = RunFromPosition(end);
 148                 RemoveRunIfSameAsPrevious(runEnd);
 149                 RemoveRunIfSameAsPrevious(runStart);
 150         }
 151         return true;
 152 }
 153
 154 void RunStyles::SetValueAt(int position, int value) {
 155         int len = 1;
 156         FillRange(position, value, len);
 157 }
 158
 159 void RunStyles::InsertSpace(int position, int insertLength) {
 160         int runStart = RunFromPosition(position);
 161         if (starts->PositionFromPartition(runStart) == position) {
 162                 int runStyle = ValueAt(position);
 163                 // Inserting at start of run so make previous longer
 164                 if (runStart == 0) {
 165                         // Inserting at start of document so ensure 0
 166                         if (runStyle) {
 167                                 styles->SetValueAt(0, 0);
 168                                 starts->InsertPartition(1, 0);
 169                                 styles->InsertValue(1, 1, runStyle);
 170                                 starts->InsertText(0, insertLength);
 171                         } else {
 172                                 starts->InsertText(runStart, insertLength);
 173                         }
 174                 } else {
 175                         if (runStyle) {
 176                                 starts->InsertText(runStart-1, insertLength);
 177                         } else {
 178                                 // Insert at end of run so do not extend style
 179                                 starts->InsertText(runStart, insertLength);
 180                         }
 181                 }
 182         } else {
 183                 starts->InsertText(runStart, insertLength);
 184         }
 185 }
 186
 187 void RunStyles::DeleteAll() {
 188         delete starts;
 189         starts = NULL;
 190         delete styles;
 191         styles = NULL;
 192         starts = new Partitioning(8);
 193         styles = new SplitVector<int>();
 194         styles->InsertValue(0, 2, 0);
 195 }
 196
 197 void RunStyles::DeleteRange(int position, int deleteLength) {
 198         int end = position + deleteLength;
 199         int runStart = RunFromPosition(position);
 200         int runEnd = RunFromPosition(end);
 201         if (runStart == runEnd) {
 202                 // Deleting from inside one run
 203                 starts->InsertText(runStart, -deleteLength);
 204         } else {
 205                 runStart = SplitRun(position);
 206                 runEnd = SplitRun(end);
 207                 starts->InsertText(runStart, -deleteLength);
 208                 // Remove each old run over the range
 209                 for (int run=runStart; run<runEnd; run++) {
 210                         RemoveRun(runStart);
 211                 }
 212                 RemoveRunIfEmpty(runStart);
 213                 RemoveRunIfSameAsPrevious(runStart);
 214         }
 215 }
 216