"use server";

import { and, asc, eq } from "drizzle-orm";
import { revalidatePath } from "next/cache";
import { redirect } from "next/navigation";
import { z } from "zod";
import { db } from "@/lib/db";
import { getCurrentSession } from "@/lib/session";
import { getWidget } from "@/modules/_core";
import { dashboards } from "@/modules/_core/schema";
import { type DashboardLayout } from "@/lib/dashboard";
import { computeDefaultLayout } from "@/lib/dashboard.server";

export type DashboardMeta = {
  id: string;
  name: string;
  slug: string;
  isDefault: boolean;
  position: number;
};

export async function listDashboards(): Promise<DashboardMeta[]> {
  const { user } = await getCurrentSession();
  const rows = await db
    .select({
      id: dashboards.id,
      name: dashboards.name,
      slug: dashboards.slug,
      isDefault: dashboards.isDefault,
      position: dashboards.position,
    })
    .from(dashboards)
    .where(eq(dashboards.userId, user.id))
    .orderBy(asc(dashboards.position), asc(dashboards.createdAt));
  return rows;
}

export async function getDefaultDashboardSlug(): Promise<string> {
  const { user } = await getCurrentSession();
  const rows = await db
    .select({ slug: dashboards.slug })
    .from(dashboards)
    .where(and(eq(dashboards.userId, user.id), eq(dashboards.isDefault, true)))
    .limit(1);
  if (rows[0]) return rows[0].slug;
  // Fallback: first dashboard by position
  const [first] = await db
    .select({ slug: dashboards.slug })
    .from(dashboards)
    .where(eq(dashboards.userId, user.id))
    .orderBy(asc(dashboards.position), asc(dashboards.createdAt))
    .limit(1);
  if (first) return first.slug;
  // No dashboards yet — insert one directly without revalidatePath (we're in a
  // render path; the redirect that follows is a fresh request anyway).
  const slug = await uniqueSlug(user.id, "home");
  await db
    .insert(dashboards)
    .values({ userId: user.id, name: "Home", slug, isDefault: false, position: 0 });
  return slug;
}

export async function getDashboardBySlug(slug: string) {
  const { user } = await getCurrentSession();
  const [row] = await db
    .select()
    .from(dashboards)
    .where(and(eq(dashboards.userId, user.id), eq(dashboards.slug, slug)))
    .limit(1);
  return row ?? null;
}

function toSlug(name: string): string {
  return (
    name
      .toLowerCase()
      .replace(/[^a-z0-9]+/g, "-")
      .replace(/^-|-$/g, "") || "dashboard"
  );
}

async function uniqueSlug(userId: string, base: string): Promise<string> {
  let slug = base;
  let attempt = 1;
  for (;;) {
    const [existing] = await db
      .select({ id: dashboards.id })
      .from(dashboards)
      .where(and(eq(dashboards.userId, userId), eq(dashboards.slug, slug)))
      .limit(1);
    if (!existing) return slug;
    attempt++;
    slug = `${base}-${attempt}`;
  }
}

export async function createDashboard(name: string): Promise<DashboardMeta> {
  const parsed = z.string().trim().min(1).max(80).parse(name);
  const { user } = await getCurrentSession();
  const slug = await uniqueSlug(user.id, toSlug(parsed));
  const rows = await db
    .insert(dashboards)
    .values({ userId: user.id, name: parsed, slug, isDefault: false, position: 9999 })
    .returning();
  const row = rows[0];
  if (!row) throw new Error("Insert failed");
  revalidatePath("/");
  return {
    id: row.id,
    name: row.name,
    slug: row.slug,
    isDefault: row.isDefault,
    position: row.position,
  };
}

export async function renameDashboard(id: string, name: string): Promise<void> {
  const parsedName = z.string().trim().min(1).max(80).parse(name);
  const { user } = await getCurrentSession();
  await db
    .update(dashboards)
    .set({ name: parsedName, updatedAt: new Date() })
    .where(and(eq(dashboards.id, id), eq(dashboards.userId, user.id)));
  revalidatePath("/");
}

export async function deleteDashboard(id: string): Promise<void> {
  const { user } = await getCurrentSession();
  const all = await db
    .select({ id: dashboards.id, isDefault: dashboards.isDefault, slug: dashboards.slug })
    .from(dashboards)
    .where(eq(dashboards.userId, user.id));
  if (all.length <= 1) throw new Error("Cannot delete your only dashboard");
  const target = all.find((d) => d.id === id);
  if (!target) throw new Error("Dashboard not found");

  await db.delete(dashboards).where(and(eq(dashboards.id, id), eq(dashboards.userId, user.id)));

  // If we deleted the default, promote another
  if (target.isDefault) {
    const next = all.find((d) => d.id !== id);
    if (next) {
      await db
        .update(dashboards)
        .set({ isDefault: true })
        .where(and(eq(dashboards.id, next.id), eq(dashboards.userId, user.id)));
    }
  }
  revalidatePath("/");
  redirect("/");
}

export async function setDefaultDashboard(id: string): Promise<void> {
  const { user } = await getCurrentSession();
  await db.update(dashboards).set({ isDefault: false }).where(eq(dashboards.userId, user.id));
  await db
    .update(dashboards)
    .set({ isDefault: true })
    .where(and(eq(dashboards.id, id), eq(dashboards.userId, user.id)));
  revalidatePath("/");
}

export async function reorderDashboards(orderedIds: string[]): Promise<void> {
  const { user } = await getCurrentSession();
  await Promise.all(
    orderedIds.map((id, i) =>
      db
        .update(dashboards)
        .set({ position: i })
        .where(and(eq(dashboards.id, id), eq(dashboards.userId, user.id))),
    ),
  );
  revalidatePath("/");
}

export async function saveDashboardLayout(id: string, layout: DashboardLayout): Promise<void> {
  const { user } = await getCurrentSession();
  // Validate each widget's config against its registered schema
  for (const placement of layout.widgets) {
    const widget = getWidget(placement.widgetId);
    if (!widget) continue;
    widget.configSchema.parse(placement.config);
  }
  await db
    .update(dashboards)
    .set({ layout: layout as unknown as Record<string, unknown>, updatedAt: new Date() })
    .where(and(eq(dashboards.id, id), eq(dashboards.userId, user.id)));
  revalidatePath("/");
}

export async function resetDashboardLayout(id: string): Promise<void> {
  const { user } = await getCurrentSession();
  const layout = computeDefaultLayout();
  await db
    .update(dashboards)
    .set({ layout: layout as unknown as Record<string, unknown>, updatedAt: new Date() })
    .where(and(eq(dashboards.id, id), eq(dashboards.userId, user.id)));
  revalidatePath("/");
}

export async function resolveWidgetConfigOptions(widgetId: string): Promise<unknown> {
  const { user, household } = await getCurrentSession();
  const widget = getWidget(widgetId);
  if (!widget?.resolveConfigOptions) return null;
  return widget.resolveConfigOptions({ userId: user.id, householdId: household.id });
}