調整邏輯: 加入連結馬上加入資料庫，每個工作階段均 update state

EHDownloader/Book.cs

@@ -6,6 +6,7 @@ using System.ComponentModel;
 using System.Linq;
 using System.Net;
 using System.Net.Http;
+using System.Runtime.InteropServices.WindowsRuntime;
 using System.Text;
 using System.Threading.Tasks;
 
@@ -28,33 +29,40 @@ namespace EHDownloader
         DownloadImageFailed,
     }
 
-    enum BookStates
+    enum BookStates:int
     {
         [Description("等待")]
-        Wait,
+        Wait = 0,
         //[Description("擷取頁面失敗")]
         //FetchError,
         [Description("載入首頁失敗")]
-        LoadFailed,
+        LoadFailed = -1,
         [Description("擷取標題失敗")]
-        FetchTitleFailed,
+        FetchTitleFailed = -2,
         [Description("擷取頁集合失敗")]
-        FetchPageSetFailed,
+        FetchPageSetFailed = -3,
         [Description("擷取頁連結失敗")]
-        FetchPageLinkFailed,
+        FetchPageLinkFailed = -4,
+        [Description("下載完成, 但是有些頁面出錯")]
+        DownloadFinishedButSomePageError = -5,
 
         [Description("擷取頁面完成")]
-        FetchCompleted,
-
-
-
+        FetchCompleted = 1,
         [Description("下載完成")]
-        DownloadCompleted,
-        [Description("下載完成, 但是有些頁面出錯")]
-        DownloadFinishedButSomePageError,
-        Compressed,
+        DownloadCompleted = 2,
+        [Description("下載並封裝完成")]
+        Compressed = 3,
     }
 
+    static class BookStateHelper
+    {
+        static public bool IsCompleted(this BookStates? state)
+        {
+            return state.HasValue && ((int)state.Value) >= (int)BookStates.Compressed;
+        }
+    }
+
+
     class Book
     {
         private const string PageSetXPath = @"//table[@class='ptb']//a";
@@ -73,9 +81,9 @@ namespace EHDownloader
 
         public List<Page> Pages { get; private set; }
 
-        public int PageCount => Pages.Count;
+        public int PageCount => Pages?.Count ?? 0;
 
-        public BookStates BookState { get; set; } = BookStates.Wait;
+        public BookStates State { get; set; } = BookStates.Wait;
 
 
         public Book(string url, string parentFolder)
@@ -105,7 +113,7 @@ namespace EHDownloader
             }
             catch (Exception ex)
             {
-                BookState = BookStates.LoadFailed;
+                State = BookStates.LoadFailed;
                 return FetchBookResults.LoadPageFailed;
             }
 
@@ -115,7 +123,7 @@ namespace EHDownloader
             }
             catch
             {
-                BookState = BookStates.FetchTitleFailed;
+                State = BookStates.FetchTitleFailed;
                 return FetchBookResults.FetchTitleFailed;
             }
 
@@ -125,7 +133,7 @@ namespace EHDownloader
                 var htmlPageSets = doc.DocumentNode.SelectNodes(PageSetXPath);
                 if (htmlPageSets == null)
                 {
-                    BookState = BookStates.FetchPageSetFailed;
+                    State = BookStates.FetchPageSetFailed;
                     return FetchBookResults.FetchPageSetFailed;
                 }
                 foreach (var htmlPageSet in htmlPageSets)
@@ -142,7 +150,7 @@ namespace EHDownloader
             }
             catch
             {
-                BookState = BookStates.FetchPageSetFailed;
+                State = BookStates.FetchPageSetFailed;
                 return FetchBookResults.FetchTitleFailed;
             }
 
@@ -170,7 +178,7 @@ namespace EHDownloader
             }
             catch 
             {
-                BookState = BookStates.FetchPageLinkFailed;
+                State = BookStates.FetchPageLinkFailed;
                 return FetchBookResults.FetchPageLinkFailed;
             }
 
@@ -180,7 +188,7 @@ namespace EHDownloader
                 Pages[i].PageNumber = i + 1;
             }
 
-            BookState = BookStates.FetchCompleted;
+            State = BookStates.FetchCompleted;
             return FetchBookResults.Completed;
         }
 
@@ -218,15 +226,16 @@ namespace EHDownloader
 
                 if (Pages.All(p => p.Result == DownloadPageResults.Completed))
                 {
-                    BookState = BookStates.DownloadCompleted;
+                    State = BookStates.DownloadCompleted;
                     return;
                 }
             }
-            BookState = BookStates.DownloadFinishedButSomePageError;
+            State = BookStates.DownloadFinishedButSomePageError;
         }
 
-        private string GetFolderName()
+        private string getFolderName()
         {
+            if (Title == null) return null;
             string folderName = Title;
             foreach (var ch in System.IO.Path.GetInvalidFileNameChars())
                 folderName = folderName.Replace(ch, ' ');
@@ -251,7 +260,7 @@ namespace EHDownloader
         public async Task CompressAsync()
         {
             string folderPath = getFolderPath();
-            if (BookState != BookStates.DownloadCompleted)
+            if (State != BookStates.DownloadCompleted)
                 return;
             if (!System.IO.Directory.Exists(ParentFolder))
                 return;
@@ -271,12 +280,19 @@ namespace EHDownloader
                 System.IO.Directory.Delete(folderPath, true);
             }
 
-            BookState = BookStates.Compressed;
+            State = BookStates.Compressed;
         }
 
         private string getFolderPath()
         {
-            return System.IO.Path.Combine(ParentFolder, GetFolderName());
+            string nane = getFolderName();
+            if (nane == null) return null;
+            return System.IO.Path.Combine(ParentFolder, nane);
+        }
+
+        public string Path
+        {
+            get => getFolderPath();
         }
     }
 

EHDownloader/DbContext.cs

@@ -4,6 +4,7 @@ using System.Collections.Generic;
 using System.Data.SQLite;
 using System.IO;
 using System.Linq;
+using System.Security.Policy;
 using System.Text;
 using System.Threading.Tasks;
 
@@ -13,23 +14,82 @@ namespace EHDownloader
     {
         public DbContext()
         {
-            if (File.Exists(Settings.GetDbPath())) return;
+            if (File.Exists(Settings.GetDbPath()))
+            {
+                checkDB();
+            }
+            else
+            {
+                createNewDB();
+            }
+        }
 
+        private void checkDB()
+        {
+            int DBVer = getDBSchemaVersion();
+            if(DBVer == 0)
+            {
+                updateDBSchema(DBVer);
+            }
+        }
+
+        private void updateDBSchema(int fromVer)
+        {
+            using (var cn = new SQLiteConnection(Settings.GetConnectString()))
+            { 
+                switch (fromVer)
+                {
+                    case 0:
+                        {
+                            // add App table and ver=1
+                            cn.Execute(@"
+                                CREATE TABLE App (DBSchemaVersion INTEGER NOT NULL);
+                                INSERT INTO App (DBSchemaVersion) VALUES (1);
+                                ALTER TABLE Book ADD COLUMN State INTEGER NOT NULL DEFAULT 3;
+                                ALTER TABLE Book ADD COLUMN Path TEXT;
+                            ");
+                        }
+                        break;
+                }
+            }   
+        }
+
+        private static void createNewDB()
+        {
             using (var cn = new SQLiteConnection(Settings.GetConnectString()))
             {
                 cn.Execute(@"
-                    CREATE TABLE Book (
-                    Url VARCHAR(256),
-                    Title VARNCHAR(256),
-                    PageCount smallint,
-                    DownloadDateTime datetime,
-                    CONSTRAINT Book_PK PRIMARY KEY (Url)
-                )");
-
+                    CREATE TABLE ""Book"" (
+	                    ""Url""	VARCHAR(256),
+	                    ""Title""	VARNCHAR(256),
+	                    ""PageCount""	smallint,
+	                    ""DownloadDateTime""	datetime,
+	                    ""State""	INTEGER NOT NULL,
+	                    ""Path""	TEXT,
+	                    CONSTRAINT ""Book_PK"" PRIMARY KEY(""Url"")
+                    );
+                    CREATE TABLE ""App"" (
+	                    ""DBSchemaVersion""	INTEGER NOT NULL
+                    );
+                    INSERT INTO App (DBSchemaVersion) VALUES (1);
+                ");
             }
         }
 
-        public bool PageIsExists(string url)
+        private int getDBSchemaVersion()
+        {
+            using (var cn = new SQLiteConnection(Settings.GetConnectString()))
+            {
+                // check App table is exists
+                var query_table_exists = "SELECT 1 FROM sqlite_master WHERE type = 'table' AND name = 'App'";
+                bool app_table_is_exists = cn.Query(query_table_exists).Any();
+                if (!app_table_is_exists) return 0;
+                var query = "select DBSchemaVersion from App";
+                return cn.Query<int>(query).FirstOrDefault();
+            }
+        }
+
+        public bool BookIsExists(string url)
         {
             using (var cn = new SQLiteConnection(Settings.GetConnectString()))
             {
@@ -39,14 +99,48 @@ namespace EHDownloader
             }
         }
 
-        public void InsertPage(Book book)
+        public bool BookIsCompleted(string url)
+        {
+            using (var cn = new SQLiteConnection(Settings.GetConnectString()))
+            {
+                var query =
+                    "select State from Book where Url=(@url)";
+                int? state = cn.Query<int?>(query, new { url }).FirstOrDefault();
+                return ((BookStates?)state).IsCompleted();
+            }
+        }
+
+        // null: book not exists
+        public BookStates? QueryBookState(string url)
+        {
+            using (var cn = new SQLiteConnection(Settings.GetConnectString()))
+            {
+                var query =
+                    "select State from Book where Url=(@url)";
+                int? state = cn.Query<int?>(query, new { url }).FirstOrDefault();
+                return (BookStates)state;
+            }
+        }
+
+        public void InsertBook(Book book)
         {
             using (var cn = new SQLiteConnection(Settings.GetConnectString()))
             {
                 var insertScript =
-                    "INSERT INTO Book VALUES (@Url,@Title,@PageCount,@DownloadDateTime)";
+                    "INSERT INTO Book VALUES (@Url,@Title,@PageCount,@DownloadDateTime,@State,@Path)";
                 cn.Execute(insertScript, book);
             }
         }
+
+        public void UpdateBook(Book book)
+        {
+            using (var cn = new SQLiteConnection(Settings.GetConnectString()))
+            {
+                var updateScript =
+                    "UPDATE Book SET Title=@Title,PageCount=@PageCount,DownloadDateTime=@DownloadDateTime,State=@State,Path=@Path " +
+                    "WHERE Url=@Url";
+                cn.Execute(updateScript, book);
+            }
+        }
     }
 }

EHDownloader/EHDownloader.csproj

@@ -114,4 +114,10 @@
     </PropertyGroup>
     <Error Condition="!Exists('..\packages\System.Data.SQLite.Core.1.0.111.0\build\net46\System.Data.SQLite.Core.targets')" Text="$([System.String]::Format('$(ErrorText)', '..\packages\System.Data.SQLite.Core.1.0.111.0\build\net46\System.Data.SQLite.Core.targets'))" />
   </Target>
+	<PropertyGroup>
+		<ContentSQLiteInteropFiles>true</ContentSQLiteInteropFiles>
+		<CopySQLiteInteropFiles>false</CopySQLiteInteropFiles>
+		<CleanSQLiteInteropFiles>false</CleanSQLiteInteropFiles>
+		<CollectSQLiteInteropFiles>false</CollectSQLiteInteropFiles>
+	</PropertyGroup>
 </Project>

EHDownloader/Form1.cs

@@ -106,18 +106,32 @@ namespace EHDownloader
         {
             if (!isEhUrl(url)) return;
             if (lv_Tasks.Items.ContainsKey(url)) return;
-            if (_dbContext.PageIsExists(url)) return;
+            // if (_dbContext.BookIsExists(url)) return;
+            await newTask(url);
+        }
+
+        private async Task newTask(string url)
+        {
+            BookStates? newBookState = _dbContext.QueryBookState(url);
+            if (newBookState.IsCompleted())
+            {
+                // 已完成
+                return;
+            }
+            Book book = new Book(url, _folder);
+            if (!newBookState.HasValue)
+                _dbContext.InsertBook(book);
+            else
+                _dbContext.UpdateBook(book);
+            
+
         ListViewItem lvi = new ListViewItem(url) { Name = url };
             lvi.SubItems.Add("Wait");
-
-            Book book = new Book(url, _folder);
             lvi.Text = url;
             lvi.Tag = book;
 
             lv_Tasks.Items.Add(lvi);
             await TryStartTask(lvi);
-
-
         }
 
         private async Task TryStartTask()
@@ -135,19 +149,21 @@ namespace EHDownloader
                 while (running)
                 {
                     
-                    lvi.SubItems[1].Text = book.BookState.GetDescription();
-                    switch (book.BookState)
+                    lvi.SubItems[1].Text = book.State.GetDescription();
+                    switch (book.State)
                     {
                         case BookStates.Wait:
                             await book.FetchAsync();
+                            _dbContext.UpdateBook(book);
                             break;
                         case BookStates.FetchCompleted:
                             await book.DownloadBookAsync(new Progress<DownloadProgressInfo>(
                                 (info) => lvi.SubItems[1].Text = $"下載中 {info.PageNumber}/{info.PageCount}"));
+                            _dbContext.UpdateBook(book);
                             break;
                         case BookStates.DownloadCompleted:
                             await book.CompressAsync();
-                            _dbContext.InsertPage(book);
+                            _dbContext.UpdateBook(book);
                             goto default;
                         case BookStates.Compressed:
                         case BookStates.LoadFailed:
@@ -178,7 +194,7 @@ namespace EHDownloader
             {
                 var lvi = lv_Tasks.Items[i];
                 var book = (Book)lvi.Tag;
-                switch (book.BookState)
+                switch (book.State)
                 {
                     case BookStates.Wait:
                     case BookStates.FetchCompleted:
@@ -190,10 +206,10 @@ namespace EHDownloader
                     case BookStates.FetchTitleFailed:
                     case BookStates.FetchPageSetFailed:
                     case BookStates.FetchPageLinkFailed:
-                        book.BookState = BookStates.Wait;
+                        book.State = BookStates.Wait;
                         continue;
                     case BookStates.DownloadFinishedButSomePageError:
-                        book.BookState = BookStates.FetchCompleted;
+                        book.State = BookStates.FetchCompleted;
                         continue;
                 }
             }