import { z } from "zod";
import { and, asc, eq } from "drizzle-orm";
import { withUser, parseBody, json, ApiError } from "@/lib/api";
import { getDb, modelPresets, promptPresets } from "@/db";
import { ids } from "@/lib/ids";
import { generationSettingsSchema } from "@/lib/chat/schemas";

export const dynamic = "force-dynamic";

/**
 * /api/presets?kind=model|prompt — CRUD for model presets and prompt presets.
 */
const kindSchema = z.enum(["model", "prompt"]);

const modelPresetSchema = z.object({
  name: z.string().min(1).max(80),
  description: z.string().max(400).nullable().optional(),
  icon: z.string().max(16).nullable().optional(),
  modelKey: z.string().min(3).max(120),
  systemPrompt: z.string().max(50_000).nullable().optional(),
  parameters: generationSettingsSchema.optional(),
  tools: z.record(z.string(), z.unknown()).optional(),
  fileSettings: z.record(z.string(), z.unknown()).optional(),
});

const promptPresetSchema = z.object({
  name: z.string().min(1).max(80),
  description: z.string().max(400).nullable().optional(),
  icon: z.string().max(16).nullable().optional(),
  systemPrompt: z.string().min(1).max(50_000),
  defaultModelKey: z.string().max(120).nullable().optional(),
  parameters: generationSettingsSchema.optional(),
  tools: z.record(z.string(), z.unknown()).optional(),
});

export const GET = withUser(async ({ user }) => {
  const db = getDb();
  const [models, prompts] = await Promise.all([
    db.select().from(modelPresets).where(eq(modelPresets.userId, user.id)).orderBy(asc(modelPresets.sortOrder), asc(modelPresets.createdAt)),
    db.select().from(promptPresets).where(eq(promptPresets.userId, user.id)).orderBy(asc(promptPresets.sortOrder), asc(promptPresets.createdAt)),
  ]);
  return json({ modelPresets: models, promptPresets: prompts });
});

export const POST = withUser(async ({ req, user }) => {
  const kind = kindSchema.parse(new URL(req.url).searchParams.get("kind"));
  const db = getDb();
  if (kind === "model") {
    const body = await parseBody(req, modelPresetSchema);
    const [row] = await db.insert(modelPresets).values({ id: ids.preset(), userId: user.id, ...body, parameters: body.parameters ?? {}, tools: body.tools ?? {}, fileSettings: body.fileSettings ?? {} }).returning();
    return json({ preset: row }, { status: 201 });
  }
  const body = await parseBody(req, promptPresetSchema);
  const [row] = await db.insert(promptPresets).values({ id: ids.prompt(), userId: user.id, ...body, parameters: body.parameters ?? {}, tools: body.tools ?? {} }).returning();
  return json({ preset: row }, { status: 201 });
});

export const PATCH = withUser(async ({ req, user }) => {
  const url = new URL(req.url);
  const kind = kindSchema.parse(url.searchParams.get("kind"));
  const id = url.searchParams.get("id");
  if (!id) throw new ApiError(400, "Missing id");
  const db = getDb();
  if (kind === "model") {
    const body = await parseBody(req, modelPresetSchema.partial());
    const [row] = await db
      .update(modelPresets)
      .set({ ...body, updatedAt: new Date() })
      .where(and(eq(modelPresets.id, id), eq(modelPresets.userId, user.id)))
      .returning();
    if (!row) throw new ApiError(404, "Preset not found", "NOT_FOUND");
    return json({ preset: row });
  }
  const body = await parseBody(req, promptPresetSchema.partial());
  const [row] = await db
    .update(promptPresets)
    .set({ ...body, updatedAt: new Date() })
    .where(and(eq(promptPresets.id, id), eq(promptPresets.userId, user.id)))
    .returning();
  if (!row) throw new ApiError(404, "Preset not found", "NOT_FOUND");
  return json({ preset: row });
});

export const DELETE = withUser(async ({ req, user }) => {
  const url = new URL(req.url);
  const kind = kindSchema.parse(url.searchParams.get("kind"));
  const id = url.searchParams.get("id");
  if (!id) throw new ApiError(400, "Missing id");
  const db = getDb();
  if (kind === "model") await db.delete(modelPresets).where(and(eq(modelPresets.id, id), eq(modelPresets.userId, user.id)));
  else await db.delete(promptPresets).where(and(eq(promptPresets.id, id), eq(promptPresets.userId, user.id)));
  return json({ ok: true });
});