[fix] percentage regression, [add] individual doc & user update (performance)

database/manager.go

@@ -23,6 +23,9 @@ var ddl string
 //go:embed update_temp_tables.sql
 var tsql string
 
+//go:embed update_document_user_statistics.sql
+var doc_user_stat_sql string
+
 func NewMgr(c *config.Config) *DBManager {
 	// Create Manager
 	dbm := &DBManager{
@@ -60,6 +63,21 @@ func (dbm *DBManager) Shutdown() error {
 	return dbm.DB.Close()
 }
 
+func (dbm *DBManager) UpdateDocumentUserStatistic(documentID string, userID string) error {
+	// Prepare Statement
+	stmt, err := dbm.DB.PrepareContext(dbm.Ctx, doc_user_stat_sql)
+	if err != nil {
+		return err
+	}
+	defer stmt.Close()
+
+	// Execute
+	if _, err := stmt.ExecContext(dbm.Ctx, documentID, userID); err != nil {
+		return err
+	}
+	return nil
+}
+
 func (dbm *DBManager) CacheTempTables() error {
 	if _, err := dbm.DB.ExecContext(dbm.Ctx, tsql); err != nil {
 		return err

database/schema.sql

@@ -136,7 +136,9 @@ CREATE TEMPORARY TABLE IF NOT EXISTS document_user_statistics (
     read_percentage REAL NOT NULL,
     percentage REAL NOT NULL,
     words_read INTEGER NOT NULL,
-    wpm REAL NOT NULL
+    wpm REAL NOT NULL,
+
+    UNIQUE(document_id, user_id) ON CONFLICT REPLACE
 );
 
 
@@ -325,6 +327,8 @@ current_progress AS (
             WHERE
                 dp.user_id = iga.user_id
                 AND dp.document_id = iga.document_id
+	    ORDER BY created_at DESC
+	    LIMIT 1
         ), end_percentage) AS percentage
     FROM intermediate_ga AS iga
     GROUP BY user_id, document_id

database/update_document_user_statistics.sql

@@ -0,0 +1,77 @@
+INSERT INTO document_user_statistics
+WITH intermediate_ga AS (
+    SELECT
+        ga1.id AS row_id,
+        ga1.user_id,
+        ga1.document_id,
+        ga1.duration,
+        ga1.start_time,
+        ga1.start_percentage,
+        ga1.end_percentage,
+
+        -- Find Overlapping Events (Assign Unique ID)
+        (
+            SELECT MIN(id)
+            FROM activity AS ga2
+            WHERE
+                ga1.document_id = ga2.document_id
+                AND ga1.user_id = ga2.user_id
+                AND ga1.start_percentage <= ga2.end_percentage
+                AND ga1.end_percentage >= ga2.start_percentage
+        ) AS group_leader
+    FROM activity AS ga1
+    WHERE
+        document_id = ?
+        AND user_id = ?
+),
+grouped_activity AS (
+    SELECT
+        user_id,
+        document_id,
+        MAX(start_time) AS start_time,
+        MIN(start_percentage) AS start_percentage,
+        MAX(end_percentage) AS end_percentage,
+        MAX(end_percentage) - MIN(start_percentage) AS read_percentage,
+        SUM(duration) AS duration
+    FROM intermediate_ga
+    GROUP BY group_leader
+),
+current_progress AS (
+    SELECT
+        user_id,
+        document_id,
+        COALESCE((
+            SELECT percentage
+            FROM document_progress AS dp
+            WHERE
+                dp.user_id = iga.user_id
+                AND dp.document_id = iga.document_id
+	    ORDER BY created_at DESC
+	    LIMIT 1
+        ), end_percentage) AS percentage
+    FROM intermediate_ga AS iga
+    GROUP BY user_id, document_id
+    HAVING MAX(start_time)
+)
+SELECT
+    ga.document_id,
+    ga.user_id,
+    MAX(start_time) AS last_read,
+    SUM(duration) AS total_time_seconds,
+    SUM(read_percentage) AS read_percentage,
+    cp.percentage,
+
+    (CAST(COALESCE(d.words, 0.0) AS REAL) * SUM(read_percentage))
+        AS words_read,
+
+    (CAST(COALESCE(d.words, 0.0) AS REAL) * SUM(read_percentage))
+    / (SUM(duration) / 60.0) AS wpm
+FROM grouped_activity AS ga
+INNER JOIN
+    current_progress AS cp
+    ON ga.user_id = cp.user_id AND ga.document_id = cp.document_id
+INNER JOIN
+    documents AS d
+    ON d.id = ga.document_id
+GROUP BY ga.document_id, ga.user_id
+ORDER BY wpm DESC;