feat(imap): 补充邮件 IMAP 元数据支持

- 为文件夹和消息增加 `UID/ModSeq` 字段，并在迁移时回填与建索引。 - 让收发、移动、标记、删除、草稿等流程同步维护 `imap_uid` 和 `imap_modseq`。 - 扩展后端与前端类型，并补充相关测试覆盖。
2026-06-24 16:23:45 +08:00
parent d28ed4adcc
commit b3669f189e
10 changed files with 533 additions and 45 deletions
@@ -0,0 +1,242 @@
+package app
+
+import (
+	"context"
+	"database/sql"
+	"math"
+	"time"
+)
+
+type imapMetadata struct {
+	UID    int64
+	ModSeq int64
+}
+
+func (a *App) migrateIMAPMetadata(ctx context.Context) error {
+	if err := a.ensureTableColumn(ctx, "folders", "uid_validity", `ALTER TABLE folders ADD COLUMN uid_validity INTEGER NOT NULL DEFAULT 0`); err != nil {
+		return err
+	}
+	if err := a.ensureTableColumn(ctx, "folders", "uid_next", `ALTER TABLE folders ADD COLUMN uid_next INTEGER NOT NULL DEFAULT 1`); err != nil {
+		return err
+	}
+	if err := a.ensureTableColumn(ctx, "folders", "highest_modseq", `ALTER TABLE folders ADD COLUMN highest_modseq INTEGER NOT NULL DEFAULT 1`); err != nil {
+		return err
+	}
+	if err := a.ensureTableColumn(ctx, "messages", "imap_uid", `ALTER TABLE messages ADD COLUMN imap_uid INTEGER NOT NULL DEFAULT 0`); err != nil {
+		return err
+	}
+	if err := a.ensureTableColumn(ctx, "messages", "imap_modseq", `ALTER TABLE messages ADD COLUMN imap_modseq INTEGER NOT NULL DEFAULT 1`); err != nil {
+		return err
+	}
+	if _, err := a.db.ExecContext(ctx, `UPDATE folders SET uid_validity=? WHERE uid_validity=0`, a.newUIDValidity()); err != nil {
+		return err
+	}
+	if _, err := a.db.ExecContext(ctx, `UPDATE folders SET uid_next=1 WHERE uid_next<1`); err != nil {
+		return err
+	}
+	if _, err := a.db.ExecContext(ctx, `UPDATE folders SET highest_modseq=1 WHERE highest_modseq<1`); err != nil {
+		return err
+	}
+	if err := a.backfillIMAPUIDs(ctx); err != nil {
+		return err
+	}
+	_, err := a.db.ExecContext(ctx, `CREATE UNIQUE INDEX IF NOT EXISTS idx_messages_folder_imap_uid ON messages(folder_id, imap_uid) WHERE folder_id IS NOT NULL AND imap_uid > 0`)
+	return err
+}
+
+func (a *App) ensureTableColumn(ctx context.Context, table, column, alterSQL string) error {
+	rows, err := a.db.QueryContext(ctx, `PRAGMA table_info(`+table+`)`)
+	if err != nil {
+		return err
+	}
+	defer rows.Close()
+	for rows.Next() {
+		var cid int
+		var name, typ string
+		var notNull int
+		var dflt any
+		var pk int
+		if err := rows.Scan(&cid, &name, &typ, &notNull, &dflt, &pk); err != nil {
+			return err
+		}
+		if name == column {
+			return nil
+		}
+	}
+	if err := rows.Err(); err != nil {
+		return err
+	}
+	_, err = a.db.ExecContext(ctx, alterSQL)
+	return err
+}
+
+func (a *App) backfillIMAPUIDs(ctx context.Context) error {
+	rows, err := a.db.QueryContext(ctx, `SELECT id FROM folders ORDER BY created_at,id`)
+	if err != nil {
+		return err
+	}
+	var folderIDs []string
+	for rows.Next() {
+		var folderID string
+		if err := rows.Scan(&folderID); err != nil {
+			rows.Close()
+			return err
+		}
+		folderIDs = append(folderIDs, folderID)
+	}
+	if err := rows.Err(); err != nil {
+		rows.Close()
+		return err
+	}
+	if err := rows.Close(); err != nil {
+		return err
+	}
+	for _, folderID := range folderIDs {
+		if err := a.backfillFolderIMAPUIDs(ctx, folderID); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (a *App) backfillFolderIMAPUIDs(ctx context.Context, folderID string) error {
+	rows, err := a.db.QueryContext(ctx, `SELECT id FROM messages WHERE folder_id=? AND imap_uid=0 ORDER BY created_at,id`, folderID)
+	if err != nil {
+		return err
+	}
+	var messageIDs []string
+	for rows.Next() {
+		var messageID string
+		if err := rows.Scan(&messageID); err != nil {
+			rows.Close()
+			return err
+		}
+		messageIDs = append(messageIDs, messageID)
+	}
+	if err := rows.Err(); err != nil {
+		rows.Close()
+		return err
+	}
+	if err := rows.Close(); err != nil {
+		return err
+	}
+	for _, messageID := range messageIDs {
+		meta, err := a.nextIMAPMetadata(ctx, a.db, folderID)
+		if err != nil {
+			return err
+		}
+		if _, err := a.db.ExecContext(ctx, `UPDATE messages SET imap_uid=?,imap_modseq=? WHERE id=?`, meta.UID, meta.ModSeq, messageID); err != nil {
+			return err
+		}
+	}
+	var maxUID, maxModSeq int64
+	if err := a.db.QueryRowContext(ctx, `SELECT COALESCE(MAX(imap_uid),0),COALESCE(MAX(imap_modseq),1) FROM messages WHERE folder_id=?`, folderID).Scan(&maxUID, &maxModSeq); err != nil {
+		return err
+	}
+	_, err = a.db.ExecContext(ctx, `UPDATE folders SET uid_next=MAX(uid_next,?),highest_modseq=MAX(highest_modseq,?) WHERE id=?`, maxUID+1, maxModSeq, folderID)
+	return err
+}
+
+func (a *App) newUIDValidity() int64 {
+	value := a.now().UTC().Unix()
+	if value <= 0 {
+		return time.Now().UTC().Unix()
+	}
+	return value
+}
+
+func (a *App) nextIMAPMetadata(ctx context.Context, db dbExecutor, folderID string) (imapMetadata, error) {
+	if folderID == "" {
+		return imapMetadata{}, nil
+	}
+	rowDB, ok := db.(dbQueryer)
+	if !ok {
+		return imapMetadata{}, nil
+	}
+	var nextUID, highestModSeq int64
+	err := rowDB.QueryRowContext(ctx, `SELECT uid_next,highest_modseq FROM folders WHERE id=?`, folderID).Scan(&nextUID, &highestModSeq)
+	if err != nil {
+		return imapMetadata{}, err
+	}
+	if nextUID < 1 {
+		nextUID = 1
+	}
+	nextModSeq := highestModSeq + 1
+	if nextModSeq < 1 {
+		nextModSeq = 1
+	}
+	if _, err := db.ExecContext(ctx, `UPDATE folders SET uid_next=?,highest_modseq=MAX(highest_modseq,?) WHERE id=?`, nextUID+1, nextModSeq, folderID); err != nil {
+		return imapMetadata{}, err
+	}
+	return imapMetadata{UID: nextUID, ModSeq: nextModSeq}, nil
+}
+
+func (a *App) bumpFolderModSeq(ctx context.Context, folderID string) (int64, error) {
+	return a.bumpFolderModSeqWithDB(ctx, a.db, folderID)
+}
+
+func (a *App) bumpFolderModSeqWithDB(ctx context.Context, db dbExecutor, folderID string) (int64, error) {
+	if folderID == "" {
+		return 0, nil
+	}
+	rowDB, ok := db.(dbQueryer)
+	if !ok {
+		return 0, nil
+	}
+	var current int64
+	if err := rowDB.QueryRowContext(ctx, `SELECT highest_modseq FROM folders WHERE id=?`, folderID).Scan(&current); err != nil {
+		if err == sql.ErrNoRows {
+			return 0, nil
+		}
+		return 0, err
+	}
+	next := current + 1
+	if next < 1 || next == math.MaxInt64 {
+		next = current
+	}
+	if _, err := db.ExecContext(ctx, `UPDATE folders SET highest_modseq=MAX(highest_modseq,?) WHERE id=?`, next, folderID); err != nil {
+		return 0, err
+	}
+	return next, nil
+}
+
+func (a *App) touchMessageIMAPModSeq(ctx context.Context, messageID string) error {
+	var folderID sql.NullString
+	if err := a.db.QueryRowContext(ctx, `SELECT folder_id FROM messages WHERE id=?`, messageID).Scan(&folderID); err != nil {
+		return err
+	}
+	if !folderID.Valid || folderID.String == "" {
+		return nil
+	}
+	modSeq, err := a.bumpFolderModSeq(ctx, folderID.String)
+	if err != nil {
+		return err
+	}
+	if modSeq == 0 {
+		return nil
+	}
+	_, err = a.db.ExecContext(ctx, `UPDATE messages SET imap_modseq=? WHERE id=?`, modSeq, messageID)
+	return err
+}
+
+func (a *App) updateMessageModSeq(ctx context.Context, messageID string, folderID string) (int64, error) {
+	if folderID == "" {
+		var dbFolderID sql.NullString
+		if err := a.db.QueryRowContext(ctx, `SELECT folder_id FROM messages WHERE id=?`, messageID).Scan(&dbFolderID); err != nil {
+			return 0, err
+		}
+		if !dbFolderID.Valid || dbFolderID.String == "" {
+			return 0, nil
+		}
+		folderID = dbFolderID.String
+	}
+	modSeq, err := a.bumpFolderModSeq(ctx, folderID)
+	if err != nil {
+		return 0, err
+	}
+	if modSeq == 0 {
+		return 0, nil
+	}
+	_, err = a.db.ExecContext(ctx, `UPDATE messages SET imap_modseq=? WHERE id=?`, modSeq, messageID)
+	return modSeq, err
+}