From 5cf1705784118c3c75ebe0a59a28777a292ed7ab Mon Sep 17 00:00:00 2001
From: RumovZ <gp5glkw78@relay.firefox.com>
Date: Fri, 8 Apr 2022 10:22:47 +0200
Subject: [PATCH] Add import_decks()

---
 .../src/import_export/package/apkg/import.rs  | 81 ++++++++++++++++++-
 1 file changed, 79 insertions(+), 2 deletions(-)

diff --git a/rslib/src/import_export/package/apkg/import.rs b/rslib/src/import_export/package/apkg/import.rs
index 861797c81..d3595bb3f 100644
--- a/rslib/src/import_export/package/apkg/import.rs
+++ b/rslib/src/import_export/package/apkg/import.rs
@@ -16,6 +16,7 @@ use zip::ZipArchive;
 
 use crate::{
     collection::CollectionBuilder,
+    decks::NormalDeck,
     import_export::{
         gather::ExchangeData,
         package::{
@@ -37,6 +38,7 @@ struct Context<'a> {
     guid_map: HashMap<String, NoteMeta>,
     remapped_notetypes: HashMap<NotetypeId, NotetypeId>,
     remapped_notes: HashMap<NoteId, NoteId>,
+    remapped_decks: HashMap<DeckId, DeckId>,
     data: ExchangeData,
     usn: Usn,
     /// Map of source media files, that do not already exist in the target.
@@ -97,8 +99,7 @@ impl Collection {
         ctx.prepare_media()?;
         ctx.import_notetypes()?;
         ctx.import_notes()?;
-
-        ctx.target_col.insert_data(&ctx.data)?;
+        ctx.import_decks()?;
         ctx.copy_media()?;
         Ok(())
     }
@@ -147,6 +148,7 @@ impl<'a> Context<'a> {
             conflicting_notes: HashSet::new(),
             remapped_notetypes: HashMap::new(),
             remapped_notes: HashMap::new(),
+            remapped_decks: HashMap::new(),
             used_media_entries: HashMap::new(),
             normalize_notes,
         })
@@ -322,6 +324,49 @@ impl<'a> Context<'a> {
         })
     }
 
+    fn import_decks(&mut self) -> Result<()> {
+        // TODO: ensure alphabetical order, so parents are seen first
+        let mut renamed_parents = Vec::new();
+
+        for mut deck in mem::take(&mut self.data.decks) {
+            deck.maybe_reparent(&renamed_parents);
+            if let Some(original) = self.get_deck_by_name(&deck)? {
+                if original.is_filtered() {
+                    deck.uniquify_name(&mut renamed_parents);
+                    self.add_deck(&mut deck)?;
+                } else {
+                    self.update_deck(&deck, original)?;
+                }
+            } else {
+                self.add_deck(&mut deck)?;
+            }
+        }
+
+        Ok(())
+    }
+
+    fn add_deck(&mut self, deck: &mut Deck) -> Result<()> {
+        let old_id = mem::take(&mut deck.id);
+        self.target_col.add_deck_inner(deck, self.usn)?;
+        self.remapped_decks.insert(old_id, deck.id);
+        Ok(())
+    }
+
+    /// Caller must ensure decks are normal.
+    fn update_deck(&mut self, deck: &Deck, original: Deck) -> Result<()> {
+        let mut new_deck = original.clone();
+        new_deck.normal_mut()?.update_with_other(deck.normal()?);
+        self.remapped_decks.insert(deck.id, new_deck.id);
+        self.target_col
+            .update_deck_inner(&mut new_deck, original, self.usn)
+    }
+
+    fn get_deck_by_name(&mut self, deck: &Deck) -> Result<Option<Deck>> {
+        self.target_col
+            .storage
+            .get_deck_by_name(deck.name.as_native_str())
+    }
+
     fn copy_media(&mut self) -> Result<()> {
         for (used, entry) in self.used_media_entries.values() {
             if *used {
@@ -332,6 +377,38 @@ impl<'a> Context<'a> {
     }
 }
 
+impl Deck {
+    fn maybe_reparent(&mut self, renamed_parents: &[(String, String)]) {
+        if let Some(new_name) = reparented_name(self.name.as_native_str(), renamed_parents) {
+            self.name = NativeDeckName::from_native_str(new_name);
+        }
+    }
+
+    fn uniquify_name(&mut self, renamed_parents: &mut Vec<(String, String)>) {
+        let name = self.name.as_native_str();
+        let new_name = format!("{name} {}", TimestampSecs::now());
+        renamed_parents.push((format!("{name}\x1f"), format!("{new_name}\x1f")));
+        self.name = NativeDeckName::from_native_str(new_name);
+    }
+}
+
+impl NormalDeck {
+    fn update_with_other(&mut self, other: &Self) {
+        self.markdown_description = other.markdown_description;
+        self.description = other.description.clone();
+        if other.config_id != 1 {
+            self.config_id = other.config_id;
+        }
+    }
+}
+
+fn reparented_name(name: &str, renamed_parents: &[(String, String)]) -> Option<String> {
+    renamed_parents.iter().find_map(|(old_parent, new_parent)| {
+        name.starts_with(old_parent)
+            .then(|| name.replacen(old_parent, new_parent, 1))
+    })
+}
+
 impl Notetype {
     fn schema_hash(&self) -> [u8; 20] {
         let mut hasher = Sha1::new();