/**
 * Drizzle Project Repository Adapter
 *
 * Implements ProjectRepository interface using Drizzle ORM.
 */

import { eq, and, inArray } from 'drizzle-orm';
import { nanoid } from 'nanoid';
import type { DrizzleDatabase } from '../../index.js';
import { projects, initiativeProjects, type Project } from '../../schema.js';
import type {
  ProjectRepository,
  CreateProjectData,
  UpdateProjectData,
} from '../project-repository.js';

export class DrizzleProjectRepository implements ProjectRepository {
  constructor(private db: DrizzleDatabase) {}

  async create(data: CreateProjectData): Promise<Project> {
    const id = nanoid();
    const now = new Date();

    const [created] = await this.db.insert(projects).values({
      id,
      ...data,
      createdAt: now,
      updatedAt: now,
    }).returning();

    return created;
  }

  async findById(id: string): Promise<Project | null> {
    const result = await this.db
      .select()
      .from(projects)
      .where(eq(projects.id, id))
      .limit(1);

    return result[0] ?? null;
  }

  async findByName(name: string): Promise<Project | null> {
    const result = await this.db
      .select()
      .from(projects)
      .where(eq(projects.name, name))
      .limit(1);

    return result[0] ?? null;
  }

  async findAll(): Promise<Project[]> {
    return this.db.select().from(projects);
  }

  async update(id: string, data: UpdateProjectData): Promise<Project> {
    const [updated] = await this.db
      .update(projects)
      .set({ ...data, updatedAt: new Date() })
      .where(eq(projects.id, id))
      .returning();

    if (!updated) {
      throw new Error(`Project not found: ${id}`);
    }

    return updated;
  }

  async delete(id: string): Promise<void> {
    const [deleted] = await this.db.delete(projects).where(eq(projects.id, id)).returning();

    if (!deleted) {
      throw new Error(`Project not found: ${id}`);
    }
  }

  // Junction ops

  async addProjectToInitiative(initiativeId: string, projectId: string): Promise<void> {
    const id = nanoid();
    const now = new Date();

    await this.db.insert(initiativeProjects).values({
      id,
      initiativeId,
      projectId,
      createdAt: now,
    });
  }

  async removeProjectFromInitiative(initiativeId: string, projectId: string): Promise<void> {
    await this.db
      .delete(initiativeProjects)
      .where(
        and(
          eq(initiativeProjects.initiativeId, initiativeId),
          eq(initiativeProjects.projectId, projectId),
        ),
      );
  }

  async findProjectsByInitiativeId(initiativeId: string): Promise<Project[]> {
    const rows = await this.db
      .select({ project: projects })
      .from(initiativeProjects)
      .innerJoin(projects, eq(initiativeProjects.projectId, projects.id))
      .where(eq(initiativeProjects.initiativeId, initiativeId));

    return rows.map((r) => r.project);
  }

  async setInitiativeProjects(initiativeId: string, projectIds: string[]): Promise<void> {
    // Get current associations
    const currentRows = await this.db
      .select({ projectId: initiativeProjects.projectId })
      .from(initiativeProjects)
      .where(eq(initiativeProjects.initiativeId, initiativeId));

    const currentIds = new Set(currentRows.map((r) => r.projectId));
    const desiredIds = new Set(projectIds);

    // Compute diff
    const toRemove = [...currentIds].filter((id) => !desiredIds.has(id));
    const toAdd = [...desiredIds].filter((id) => !currentIds.has(id));

    // Remove
    if (toRemove.length > 0) {
      await this.db
        .delete(initiativeProjects)
        .where(
          and(
            eq(initiativeProjects.initiativeId, initiativeId),
            inArray(initiativeProjects.projectId, toRemove),
          ),
        );
    }

    // Add
    if (toAdd.length > 0) {
      const now = new Date();
      await this.db.insert(initiativeProjects).values(
        toAdd.map((projectId) => ({
          id: nanoid(),
          initiativeId,
          projectId,
          createdAt: now,
        })),
      );
    }
  }
}