// drizzle.service.ts
import { HttpException, HttpStatus, Injectable } from '@nestjs/common';
import { and, eq, isNull } from 'drizzle-orm';
import { drizzle } from 'drizzle-orm/libsql';
import { Deck, User } from '../db/schema';

@Injectable()
export class DrizzleService {
  private db = drizzle('file:local.db');

  async getDecks(user: User) {
    return this.db.select().from(Deck).where(eq(Deck.user, user.email));
  }

  async createDeck(deckname: string, user: User) {
    const result = await this.db.insert(Deck).values({ deckname, user: user.email }).returning();
    return { status: 'success', deck: result };
  }

  async getDeckByName(deckname: string, user: User) {
    return this.db
      .select()
      .from(Deck)
      .where(and(eq(Deck.deckname, deckname), eq(Deck.user, user.email)));
  }

  async deleteDeck(deckname: string, user: User) {
    const existingDeck = await this.getDeckByName(deckname, user);
    if (existingDeck.length === 0) {
      throw new HttpException('Deck not found', HttpStatus.NOT_FOUND);
    }

    await this.db.delete(Deck).where(and(eq(Deck.deckname, deckname), eq(Deck.user, user.email)));
    return { status: 'success' };
  }

  async renameDeck(oldDeckname: string, newDeckname: string, user: User) {
    const existingDeck = await this.getDeckByName(oldDeckname, user);
    if (existingDeck.length === 0) {
      throw new HttpException('Deck not found', HttpStatus.NOT_FOUND);
    }

    const existingNewDeck = await this.getDeckByName(newDeckname, user);
    if (existingNewDeck.length > 0) {
      throw new HttpException('Deck with the new name already exists', HttpStatus.CONFLICT);
    }

    await this.db.update(Deck).set({ deckname: newDeckname }).where(eq(Deck.deckname, oldDeckname));
    return { status: 'success', message: 'Deck renamed successfully' };
  }

  async updateImage(data: { deckname: string; bildname: string; bildid: string; boxes: Array<{ x1: number; x2: number; y1: number; y2: number }> }, user: User) {
    const existingDeck = await this.getDeckByName(data.deckname, user);
    if (existingDeck.length === 0) {
      throw new HttpException('Deck not found', HttpStatus.NOT_FOUND);
    }

    await this.db.delete(Deck).where(and(eq(Deck.deckname, data.deckname), eq(Deck.bildid, data.bildid)));

    const insertedImages: any = [];
    for (let index = 0; index < data.boxes.length; index++) {
      const box = data.boxes[index];
      const result = await this.db
        .insert(Deck)
        .values({
          deckname: data.deckname,
          bildname: data.bildname,
          bildid: data.bildid,
          iconindex: index,
          x1: box.x1,
          x2: box.x2,
          y1: box.y1,
          y2: box.y2,
          user: 'andreas.knuth@gmail.com',
        })
        .returning();
      insertedImages.push(result);
    }

    return { status: 'success', inserted_images: insertedImages };
  }

  async deleteImagesByBildId(bildid: string) {
    const affectedDecks = await this.db.select({ deckname: Deck.deckname }).from(Deck).where(eq(Deck.bildid, bildid)).all();

    if (affectedDecks.length === 0) {
      throw new HttpException('No entries found for the given image ID', HttpStatus.NOT_FOUND);
    }

    await this.db.delete(Deck).where(eq(Deck.bildid, bildid));

    for (const deck of affectedDecks) {
      const remainingImages = await this.db
        .select()
        .from(Deck)
        .where(and(eq(Deck.deckname, deck.deckname), eq(Deck.bildid, bildid)))
        .all();

      if (remainingImages.length === 0) {
        const emptyDeckEntry = await this.db
          .select()
          .from(Deck)
          .where(and(eq(Deck.deckname, deck.deckname), isNull(Deck.bildid)))
          .all();

        if (emptyDeckEntry.length === 0) {
          await this.db.insert(Deck).values({ deckname: deck.deckname, user: 'andreas.knuth@gmail.com' });
        }
      }
    }

    return {
      status: 'success',
      message: `All entries for image ID "${bildid}" have been deleted.`,
    };
  }

  async moveImage(bildid: string, targetDeckId: string) {
    const existingImages = await this.db.select().from(Deck).where(eq(Deck.bildid, bildid)).all();

    if (existingImages.length === 0) {
      throw new HttpException('No entries found for the given image ID', HttpStatus.NOT_FOUND);
    }

    await this.db.update(Deck).set({ deckname: targetDeckId }).where(eq(Deck.bildid, bildid));

    return { status: 'success', moved_entries: existingImages.length };
  }

  async updateBox(
    boxId: number,
    data: {
      due?: number;
      ivl?: number;
      factor?: number;
      reps?: number;
      lapses?: number;
      isGraduated?: boolean;
    },
  ) {
    const updateData: any = { ...data };
    if (typeof data.isGraduated === 'boolean') {
      updateData.isGraduated = Number(data.isGraduated);
    }

    const result = await this.db.update(Deck).set(updateData).where(eq(Deck.id, boxId));

    if (result.rowsAffected === 0) {
      throw new HttpException('Box not found', HttpStatus.NOT_FOUND);
    }

    return { status: 'success' };
  }
}