//! Deck operations and deck membership lookups.

use rusqlite::{params, OptionalExtension};

use crate::db::REF_DB;
use crate::error::Result;
use crate::model::{CardRef, ColorSet, Deck, DeckEntry};
use crate::Catalog;

impl Catalog {
    /// Create a deck. `commander_oracle_id` is optional.
    pub fn create_deck(&self, name: &str, commander_oracle_id: Option<&str>) -> Result<Deck> {
        self.conn.execute(
            "INSERT INTO decks(name, commander_oracle_id) VALUES (?1, ?2)",
            params![name, commander_oracle_id],
        )?;
        let id = self.conn.last_insert_rowid();
        self.get_deck(id)
            .map(|d| d.expect("just-inserted deck must exist"))
    }

    pub fn get_deck(&self, id: i64) -> Result<Option<Deck>> {
        Ok(self
            .conn
            .query_row(
                "SELECT id, name, format, commander_oracle_id, notes FROM decks WHERE id = ?1",
                params![id],
                Self::map_deck,
            )
            .optional()?)
    }

    pub fn list_decks(&self) -> Result<Vec<Deck>> {
        let mut stmt = self.conn.prepare(
            "SELECT id, name, format, commander_oracle_id, notes
             FROM decks ORDER BY name COLLATE NOCASE",
        )?;
        let rows = stmt
            .query_map([], Self::map_deck)?
            .collect::<std::result::Result<Vec<_>, _>>()?;
        Ok(rows)
    }

    pub fn delete_deck(&self, id: i64) -> Result<()> {
        // ON DELETE CASCADE clears deck_cards.
        self.conn
            .execute("DELETE FROM decks WHERE id = ?1", params![id])?;
        Ok(())
    }

    /// Set how many copies of a card belong to a deck. `quantity <= 0` removes
    /// the card from the deck. Upserts on (deck_id, oracle_id).
    pub fn set_deck_card(
        &self,
        deck_id: i64,
        oracle_id: &str,
        quantity: i64,
        is_commander: bool,
    ) -> Result<()> {
        if quantity <= 0 {
            self.conn.execute(
                "DELETE FROM deck_cards WHERE deck_id = ?1 AND oracle_id = ?2",
                params![deck_id, oracle_id],
            )?;
            return Ok(());
        }
        self.conn.execute(
            "INSERT INTO deck_cards(deck_id, oracle_id, quantity, is_commander)
             VALUES (?1, ?2, ?3, ?4)
             ON CONFLICT(deck_id, oracle_id) DO UPDATE SET
               quantity = excluded.quantity,
               is_commander = excluded.is_commander",
            params![deck_id, oracle_id, quantity, is_commander as i64],
        )?;
        Ok(())
    }

    /// All cards in a deck — owned or not — with their in-deck quantity and how
    /// many copies are owned (0 if the card isn't in the library). Callers split
    /// this into "in your library" vs "not owned" groups.
    pub fn deck_contents(&self, deck_id: i64) -> Result<Vec<DeckEntry>> {
        let mut stmt = self.conn.prepare(&format!(
            "SELECT dc.quantity, dc.is_commander, COALESCE(lc.quantity_owned, 0),
                    oc.oracle_id, oc.name, oc.mana_value, oc.colors, oc.color_identity,
                    oc.type_line, {image}, {back}
             FROM deck_cards dc
             JOIN {REF_DB}.oracle_cards oc ON oc.oracle_id = dc.oracle_id
             LEFT JOIN library_cards lc ON lc.oracle_id = dc.oracle_id
             WHERE dc.deck_id = ?1
             ORDER BY oc.name COLLATE NOCASE",
            image = crate::db::image_subquery("image_uri"),
            back = crate::db::image_subquery("back_image_uri")
        ))?;
        let rows = stmt
            .query_map(params![deck_id], |r| {
                Ok(DeckEntry {
                    quantity: r.get(0)?,
                    is_commander: r.get::<_, i64>(1)? != 0,
                    quantity_owned: r.get(2)?,
                    card: CardRef {
                        oracle_id: r.get(3)?,
                        name: r.get(4)?,
                        mana_value: r.get(5)?,
                        colors: ColorSet(r.get::<_, i64>(6)? as u8),
                        color_identity: ColorSet(r.get::<_, i64>(7)? as u8),
                        type_line: r.get(8)?,
                        image_uri: r.get::<_, Option<String>>(9)?.unwrap_or_default(),
                        back_image_uri: r.get::<_, Option<String>>(10)?.unwrap_or_default(),
                    },
                })
            })?
            .collect::<std::result::Result<Vec<_>, _>>()?;
        Ok(rows)
    }

    /// The decks a given card is currently assigned to.
    pub fn card_decks(&self, oracle_id: &str) -> Result<Vec<Deck>> {
        let mut stmt = self.conn.prepare(
            "SELECT d.id, d.name, d.format, d.commander_oracle_id, d.notes
             FROM deck_cards dc JOIN decks d ON d.id = dc.deck_id
             WHERE dc.oracle_id = ?1
             ORDER BY d.name COLLATE NOCASE",
        )?;
        let rows = stmt
            .query_map(params![oracle_id], Self::map_deck)?
            .collect::<std::result::Result<Vec<_>, _>>()?;
        Ok(rows)
    }

    fn map_deck(r: &rusqlite::Row) -> rusqlite::Result<Deck> {
        Ok(Deck {
            id: r.get(0)?,
            name: r.get(1)?,
            format: r.get(2)?,
            commander_oracle_id: r.get(3)?,
            notes: r.get(4)?,
        })
    }

    /// Set the deck's format (e.g. "Commander"). Empty string clears it.
    pub fn set_deck_format(&self, deck_id: i64, format: &str) -> Result<()> {
        self.conn.execute(
            "UPDATE decks SET format = ?1 WHERE id = ?2",
            params![format, deck_id],
        )?;
        Ok(())
    }

    /// Set (or clear, with `None`) the deck's commander card. Also marks/unmarks
    /// the corresponding deck_cards row as the commander when present.
    pub fn set_deck_commander(&self, deck_id: i64, oracle_id: Option<&str>) -> Result<()> {
        self.conn.execute(
            "UPDATE decks SET commander_oracle_id = ?1 WHERE id = ?2",
            params![oracle_id, deck_id],
        )?;
        // Reset any existing commander flag, then set it on the chosen card.
        self.conn.execute(
            "UPDATE deck_cards SET is_commander = 0 WHERE deck_id = ?1",
            params![deck_id],
        )?;
        if let Some(oid) = oracle_id {
            self.conn.execute(
                "UPDATE deck_cards SET is_commander = 1 WHERE deck_id = ?1 AND oracle_id = ?2",
                params![deck_id, oid],
            )?;
        }
        Ok(())
    }
}

#[cfg(test)]
mod tests {
    use crate::test_support;

    #[test]
    fn deck_membership_visible_from_library() {
        let fx = test_support::make();
        let cat = &fx.catalog;

        cat.add_owned("llanowar-elves", 4).unwrap();
        let elves = cat.create_deck("Elfball", Some("llanowar-elves")).unwrap();
        cat.set_deck_card(elves.id, "llanowar-elves", 4, false)
            .unwrap();

        // card_decks reports membership.
        let decks = cat.card_decks("llanowar-elves").unwrap();
        assert_eq!(decks.len(), 1);
        assert_eq!(decks[0].name, "Elfball");

        // list_library surfaces the deck name on the card row.
        let lib = cat.list_library().unwrap();
        let row = lib
            .iter()
            .find(|c| c.card.oracle_id == "llanowar-elves")
            .unwrap();
        assert_eq!(row.decks, vec!["Elfball".to_string()]);
        assert_eq!(row.quantity_assigned, 4);
        assert!(!row.is_over_assigned());
    }

    #[test]
    fn over_assignment_detected_across_decks() {
        let fx = test_support::make();
        let cat = &fx.catalog;
        cat.add_owned("sol-ring", 1).unwrap(); // own one physical copy

        let a = cat.create_deck("Deck A", None).unwrap();
        let b = cat.create_deck("Deck B", None).unwrap();
        cat.set_deck_card(a.id, "sol-ring", 1, false).unwrap();
        cat.set_deck_card(b.id, "sol-ring", 1, false).unwrap();

        let lib = cat.list_library().unwrap();
        let sol = lib.iter().find(|c| c.card.oracle_id == "sol-ring").unwrap();
        assert_eq!(sol.quantity_assigned, 2);
        assert_eq!(sol.quantity_owned, 1);
        assert!(sol.is_over_assigned());
        assert_eq!(sol.decks.len(), 2);
    }

    #[test]
    fn format_and_commander_metadata() {
        let fx = test_support::make();
        let cat = &fx.catalog;
        let d = cat.create_deck("EDH", None).unwrap();
        assert_eq!(d.format, "");

        cat.set_deck_format(d.id, "Commander").unwrap();
        cat.set_deck_card(d.id, "llanowar-elves", 1, false).unwrap();
        cat.set_deck_commander(d.id, Some("llanowar-elves")).unwrap();

        let d = cat.get_deck(d.id).unwrap().unwrap();
        assert_eq!(d.format, "Commander");
        assert_eq!(d.commander_oracle_id.as_deref(), Some("llanowar-elves"));

        // The card is flagged as commander in the deck.
        let commander = cat
            .deck_contents(d.id)
            .unwrap()
            .into_iter()
            .find(|e| e.card.oracle_id == "llanowar-elves")
            .unwrap();
        assert!(commander.is_commander);

        // Clearing works.
        cat.set_deck_commander(d.id, None).unwrap();
        assert_eq!(
            cat.get_deck(d.id).unwrap().unwrap().commander_oracle_id,
            None
        );
    }

    #[test]
    fn deck_contents_include_owned_and_unowned() {
        let fx = test_support::make();
        let cat = &fx.catalog;
        cat.add_owned("llanowar-elves", 4).unwrap(); // owned
        // serra-angel intentionally NOT owned.

        let d = cat.create_deck("Mixed", None).unwrap();
        cat.set_deck_card(d.id, "llanowar-elves", 4, false).unwrap();
        cat.set_deck_card(d.id, "serra-angel", 1, true).unwrap();

        let contents = cat.deck_contents(d.id).unwrap();
        assert_eq!(contents.len(), 2);

        let owned: Vec<_> = contents.iter().filter(|e| e.quantity_owned > 0).collect();
        let unowned: Vec<_> = contents.iter().filter(|e| e.quantity_owned == 0).collect();
        assert_eq!(owned.len(), 1);
        assert_eq!(owned[0].card.name, "Llanowar Elves");
        assert_eq!(owned[0].quantity, 4);
        assert_eq!(unowned.len(), 1);
        assert_eq!(unowned[0].card.name, "Serra Angel");
        assert!(unowned[0].is_commander);
    }

    #[test]
    fn setting_zero_removes_and_cascade_on_delete() {
        let fx = test_support::make();
        let cat = &fx.catalog;
        let d = cat.create_deck("Temp", None).unwrap();
        cat.set_deck_card(d.id, "lightning-bolt", 2, false).unwrap();
        cat.set_deck_card(d.id, "lightning-bolt", 0, false).unwrap();
        assert!(cat.card_decks("lightning-bolt").unwrap().is_empty());

        cat.set_deck_card(d.id, "lightning-bolt", 1, false).unwrap();
        cat.delete_deck(d.id).unwrap();
        assert!(cat.card_decks("lightning-bolt").unwrap().is_empty());
    }
}