import { generateObject } from "ai";
import { z } from "zod";
import { resolveModel, type AiConfig } from "../factory";

const VariationsOutputSchema = z.object({
  variations: z.array(z.object({
    title: z.string(),
    description: z.string(),
    changedIngredients: z.array(z.object({
      original: z.string(),
      replacement: z.string(),
      note: z.string().optional(),
    })),
    changedSteps: z.array(z.object({
      stepNumber: z.number().int(),
      change: z.string(),
    })).optional(),
    dietaryTags: z.object({
      vegan: z.boolean().optional(),
      vegetarian: z.boolean().optional(),
      glutenFree: z.boolean().optional(),
      dairyFree: z.boolean().optional(),
      nutFree: z.boolean().optional(),
      halal: z.boolean().optional(),
      kosher: z.boolean().optional(),
    }).optional(),
  })),
});

export type VariationSuggestion = z.infer<typeof VariationsOutputSchema>["variations"][number];

const LANG: Record<string, string> = { en: "English", fr: "French" };

export async function suggestVariations(
  recipe: {
    title: string;
    description?: string | null;
    ingredients: Array<{ rawName: string; quantity?: string | null; unit?: string | null }>;
    steps: Array<{ instruction: string }>;
  },
  count = 3,
  config?: AiConfig & { userContext?: string },
  directions?: string,
  locale?: string
): Promise<VariationSuggestion[]> {
  const model = resolveModel(config);
  const lang = LANG[locale ?? "en"] ?? "English";

  const recipeText = [
    `Recipe: ${recipe.title}`,
    recipe.description ? `Description: ${recipe.description}` : "",
    `Ingredients: ${recipe.ingredients.map((i) => `${i.quantity ?? ""} ${i.unit ?? ""} ${i.rawName}`.trim()).join(", ")}`,
    `Steps: ${recipe.steps.map((s, i) => `${i + 1}. ${s.instruction}`).join(" | ")}`,
  ].filter(Boolean).join("\n");

  const directionsClause = directions?.trim()
    ? `\n\nUser directions: ${directions.trim()}`
    : "";

  const { object } = await generateObject({
    model,
    schema: VariationsOutputSchema,
    system:
      `You are a creative chef. Suggest meaningful variations of recipes — dietary adaptations, flavor profiles, technique changes. Each variation should be distinct and practical. Respond in ${lang}.${config?.userContext ? `\n\nUser preferences and context:\n${config.userContext}` : ""}`,
    prompt: `Suggest ${count} variations of this recipe:\n\n${recipeText}${directionsClause}`,
  });

  return object.variations;
}