source: oup/current/DataAccess/ConnectionManager.pas@ 319

Last change on this file since 319 was 247, checked in by alloc, 17 years ago
File size: 6.8 KB
Line 
1unit ConnectionManager;
2interface
3
4uses TypeDefs, DataAccess, Access_OniArchive, Access_OUP_ADB, Access_OniSplitArchive;
5
6type
7 TConnections = array of TDataAccess;
8
9 TConnectionListChangedEvent = procedure of object;
10
11
12 TConnectionManager = class
13 private
14 FConnections: TConnections;
15 FLastID: Integer;
16 FConnectionListChanged: TConnectionListChangedEvent;
17 function GetConnectionCount: Integer;
18 function GetConnection(ConnectionID: Integer): TDataAccess;
19 function GetConnectionByIndex(Index: Integer): TDataAccess;
20 function GetConnectionIndex(ConnectionID: Integer): Integer;
21 procedure RemoveConnection(ArrayIndex: Integer);
22 protected
23 public
24 property Count: Integer read GetConnectionCount;
25 property Connection[ConnectionID: Integer]: TDataAccess read GetConnection;
26 property ConnectionByIndex[Index: Integer]: TDataAccess read GetConnectionByIndex;
27 property ConnectionIndexByID[ConnectionID: Integer]: Integer read GetConnectionIndex;
28 property OnCoonnectionListChanged: TConnectionListChangedEvent read FConnectionListChanged write FConnectionListChanged;
29
30 constructor Create;
31 function Close: Boolean;
32
33 function OpenConnection(FileName: String; var Msg: TStatusMessages): Integer;
34 function CloseConnectionByIndex(Index: Integer; var Msg: TStatusMessages): Boolean; overload;
35 function CloseConnection(ID: Integer; var Msg: TStatusMessages): Boolean; overload;
36 function CloseConnection(FileName: String; var Msg: TStatusMessages): Boolean; overload;
37 function FileOpened(FileName: String): Integer;
38 published
39 end;
40
41
42var
43 ConManager: TConnectionManager;
44
45
46implementation
47uses
48 SysUtils, Dialogs;
49
50(*
51 Implementation of TConnectionManager
52*)
53
54
55function TConnectionManager.GetConnectionCount: Integer;
56begin
57 Result := Length(FConnections);
58end;
59
60function TConnectionManager.GetConnectionIndex(ConnectionID: Integer): Integer;
61var
62 i: Integer;
63begin
64 Result := -1;
65 if Count > 0 then
66 for i := 0 to Count - 1 do
67 if ConnectionByIndex[i].ConnectionID = ConnectionID then
68 begin
69 Result := i;
70 Break;
71 end;
72end;
73
74function TConnectionManager.GetConnection(ConnectionID: Integer): TDataAccess;
75var
76 i: Integer;
77begin
78 Result := nil;
79 if Length(FConnections) > 0 then
80 begin
81 for i := 0 to High(FConnections) do
82 begin
83 if FConnections[i].ConnectionID = ConnectionID then
84 begin
85 Result := FConnections[i];
86 Break;
87 end;
88 end;
89 if i = Length(FConnections) then
90 ShowMessage('Couldn''t find specified ConnectionID (' +
91 IntToStr(ConnectionID) + '). Please contact developer!!!');
92 end;
93end;
94
95
96function TConnectionManager.GetConnectionByIndex(Index: Integer): TDataAccess;
97begin
98 Result := nil;
99 if index < Length(FConnections) then
100 begin
101 Result := FConnections[index];
102 end;
103end;
104
105constructor TConnectionManager.Create;
106begin
107 inherited;
108 FLastID := 0;
109end;
110
111function TConnectionManager.Close: Boolean;
112begin
113 Result := False;
114 if Length(FConnections) > 0 then
115 Exit;
116
117 inherited;
118end;
119
120
121
122function TConnectionManager.OpenConnection(FileName: String; var Msg: TStatusMessages): Integer;
123var
124 i: Integer;
125 ext: String;
126 backend: TDataBackend;
127 CreateMsg: TStatusMessages;
128begin
129 Msg := SM_UnknownError;
130 Result := -1;
131
132 if Length(FConnections) > 0 then
133 begin
134 for i := 0 to High(FConnections) do
135 begin
136 if FConnections[i].FileName = FileName then
137 begin
138 Result := FConnections[i].ConnectionID;
139 Msg := SM_AlreadyOpened;
140 Exit;
141 end;
142 end;
143 end;
144
145 if not FileExists(FileName) then
146 begin
147 Msg := SM_FileNotFound;
148 Exit;
149 end;
150
151 ext := UpperCase(ExtractFileExt(FileName));
152
153 if ext = '.OLDB' then
154 backend := DB_ADB
155 else if ext = '.DAT' then
156 backend := DB_ONI
157 else if ext = '.ONI' then
158 backend := DB_ONISPLIT
159 else
160 begin
161 Msg := SM_UnknownExtension;
162 Exit;
163 end;
164
165 SetLength(FConnections, Length(FConnections) + 1);
166 i := High(FConnections);
167 case backend of
168 DB_ONI:
169 FConnections[i] := TAccess_OniArchive.Create(FileName, FLastID + 1, CreateMsg);
170 DB_ADB:
171 FConnections[i] := TAccess_OUP_ADB.Create(FileName, FLastID + 1, CreateMsg);
172 DB_ONISPLIT:
173 FConnections[i] := TAccess_OniSplitArchive.Create(FileName, FLastID + 1, CreateMsg);
174 end;
175
176 if CreateMsg = SM_OK then
177 begin
178 FLastID := FConnections[i].ConnectionID;
179 Result := FLastID;
180 Msg := SM_OK;
181 end
182 else
183 begin
184 FConnections[i].Close;
185 FConnections[i] := nil;
186 SetLength(FConnections, Length(FConnections) - 1);
187 Msg := CreateMsg;
188 end;
189end;
190
191
192procedure TConnectionManager.RemoveConnection(ArrayIndex: Integer);
193var
194 i: Integer;
195begin
196 if Length(FConnections) > 1 then
197 begin
198 for i := ArrayIndex to High(FConnections) - 1 do
199 begin
200 FConnections[i] := FConnections[i + 1];
201 end;
202 end;
203 SetLength(FConnections, Length(FConnections) - 1);
204end;
205
206function TConnectionManager.CloseConnectionByIndex(Index: Integer; var Msg: TStatusMessages): Boolean;
207begin
208 Msg := SM_UnknownError;
209 Result := False;
210
211 if Index < Length(FConnections) then
212 begin
213 FConnections[Index].Close;
214 RemoveConnection(Index);
215 Msg := SM_OK;
216 Result := True;
217 end;
218end;
219
220function TConnectionManager.CloseConnection(ID: Integer; var Msg: TStatusMessages): Boolean;
221var
222 i: Integer;
223begin
224 Msg := SM_UnknownError;
225 Result := False;
226
227 if Length(FConnections) > 0 then
228 begin
229 for i := 0 to High(FConnections) do
230 begin
231 if FConnections[i].ConnectionID = ID then
232 begin
233 FConnections[i].Close;
234 RemoveConnection(i);
235 Msg := SM_OK;
236 Result := True;
237 Exit;
238 end;
239 end;
240 end;
241end;
242
243function TConnectionManager.CloseConnection(FileName: String; var Msg: TStatusMessages): Boolean;
244var
245 i: Integer;
246begin
247 Msg := SM_UnknownError;
248 Result := False;
249
250 if Length(FConnections) > 0 then
251 begin
252 for i := 0 to High(FConnections) do
253 begin
254 if FConnections[i].FileName = FileName then
255 begin
256 FConnections[i].Close;
257 RemoveConnection(i);
258 Msg := SM_OK;
259 Result := True;
260 Exit;
261 end;
262 end;
263 end;
264end;
265
266
267function TConnectionManager.FileOpened(FileName: String): Integer;
268var
269 i: Integer;
270begin
271 Result := -1;
272 if Length(FConnections) > 0 then
273 for i := 0 to High(FConnections) do
274 if FConnections[i].FileName = FileName then
275 begin
276 Result := FConnections[i].ConnectionID;
277 Exit;
278 end;
279end;
280
281
282initialization
283 ConManager := TConnectionManager.Create;
284finalization
285 ConManager.Free;
286end.
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