import { z } from "zod";
import { protectedProcedure, router } from "../_core/trpc";
import { TRPCError } from "@trpc/server";
import { getDb } from "../db";
import { catalogueFormation } from "../../drizzle/schema";
import { eq, like, or, and } from "drizzle-orm";

// ─── Helpers ────────────────────────────────────────────────────────────────

function isAdmin(role: string) {
  return role === "admin";
}

// ─── Router ─────────────────────────────────────────────────────────────────

export const catalogueRouter = router({
  /** Lister toutes les formations du catalogue (accessible à tous les utilisateurs connectés) */
  list: protectedProcedure
    .input(
      z.object({
        search: z.string().optional(),
        theme: z.string().optional(),
        validateeItinova: z.boolean().optional(),
        opcoEligible: z.boolean().optional(),
      }).optional()
    )
    .query(async ({ input }) => {
      const db = await getDb();
      if (!db) throw new TRPCError({ code: "INTERNAL_SERVER_ERROR", message: "DB non disponible" });

      const rows = await db.select().from(catalogueFormation);

      let filtered = rows.filter(r => r.actif);

      if (input?.search) {
        const s = input.search.toLowerCase();
        filtered = filtered.filter(r =>
          r.intitule.toLowerCase().includes(s) ||
          (r.theme ?? "").toLowerCase().includes(s) ||
          (r.motsCles ?? "").toLowerCase().includes(s) ||
          (r.prestataire ?? "").toLowerCase().includes(s)
        );
      }
      if (input?.theme) {
        filtered = filtered.filter(r => r.theme === input.theme);
      }
      if (input?.validateeItinova !== undefined) {
        filtered = filtered.filter(r => r.validateeItinova === input.validateeItinova);
      }
      if (input?.opcoEligible !== undefined) {
        filtered = filtered.filter(r => r.opcoEligible === input.opcoEligible);
      }

      return filtered;
    }),

  /** Obtenir une formation par ID */
  getById: protectedProcedure
    .input(z.object({ id: z.number() }))
    .query(async ({ input }) => {
      const db = await getDb();
      if (!db) throw new TRPCError({ code: "INTERNAL_SERVER_ERROR", message: "DB non disponible" });
      const rows = await db.select().from(catalogueFormation).where(eq(catalogueFormation.id, input.id));
      if (!rows[0]) throw new TRPCError({ code: "NOT_FOUND", message: "Formation introuvable" });
      return rows[0];
    }),

  /** Créer une formation dans le catalogue (admin uniquement) */
  create: protectedProcedure
    .input(
      z.object({
        intitule: z.string().min(1),
        theme: z.string().optional(),
        motsCles: z.string().optional(),
        duree: z.string().optional(),
        prestataire: z.string().optional(),
        description: z.string().optional(),
        objectifs: z.string().optional(),
        publicConcerne: z.string().optional(),
        validateeItinova: z.boolean().optional(),
        opcoEligible: z.boolean().optional(),
        budgetOpco: z.string().optional(),
        referenceOpco: z.string().optional(),
        source: z.string().optional(),
      })
    )
    .mutation(async ({ ctx, input }) => {
      if (!isAdmin(ctx.user.role)) {
        throw new TRPCError({ code: "FORBIDDEN", message: "Réservé aux administrateurs" });
      }
      const db = await getDb();
      if (!db) throw new TRPCError({ code: "INTERNAL_SERVER_ERROR", message: "DB non disponible" });

      await db.insert(catalogueFormation).values({
        intitule: input.intitule,
        theme: input.theme ?? null,
        motsCles: input.motsCles ?? null,
        duree: input.duree ?? null,
        prestataire: input.prestataire ?? null,
        description: input.description ?? null,
        objectifs: input.objectifs ?? null,
        publicConcerne: input.publicConcerne ?? null,
        validateeItinova: input.validateeItinova ?? false,
        opcoEligible: input.opcoEligible ?? false,
        budgetOpco: input.budgetOpco ? input.budgetOpco : null,
        referenceOpco: input.referenceOpco ?? null,
        source: input.source ?? "manuel",
        actif: true,
      });

      return { success: true };
    }),

  /** Mettre à jour une formation du catalogue (admin uniquement) */
  update: protectedProcedure
    .input(
      z.object({
        id: z.number(),
        intitule: z.string().min(1).optional(),
        theme: z.string().optional(),
        motsCles: z.string().optional(),
        duree: z.string().optional(),
        prestataire: z.string().optional(),
        description: z.string().optional(),
        objectifs: z.string().optional(),
        publicConcerne: z.string().optional(),
        validateeItinova: z.boolean().optional(),
        opcoEligible: z.boolean().optional(),
        budgetOpco: z.string().optional(),
        referenceOpco: z.string().optional(),
        actif: z.boolean().optional(),
      })
    )
    .mutation(async ({ ctx, input }) => {
      if (!isAdmin(ctx.user.role)) {
        throw new TRPCError({ code: "FORBIDDEN", message: "Réservé aux administrateurs" });
      }
      const db = await getDb();
      if (!db) throw new TRPCError({ code: "INTERNAL_SERVER_ERROR", message: "DB non disponible" });

      const { id, ...rest } = input;
      const updateData: Record<string, unknown> = {};
      if (rest.intitule !== undefined) updateData.intitule = rest.intitule;
      if (rest.theme !== undefined) updateData.theme = rest.theme;
      if (rest.motsCles !== undefined) updateData.motsCles = rest.motsCles;
      if (rest.duree !== undefined) updateData.duree = rest.duree;
      if (rest.prestataire !== undefined) updateData.prestataire = rest.prestataire;
      if (rest.description !== undefined) updateData.description = rest.description;
      if (rest.objectifs !== undefined) updateData.objectifs = rest.objectifs;
      if (rest.publicConcerne !== undefined) updateData.publicConcerne = rest.publicConcerne;
      if (rest.validateeItinova !== undefined) updateData.validateeItinova = rest.validateeItinova;
      if (rest.opcoEligible !== undefined) updateData.opcoEligible = rest.opcoEligible;
      if (rest.budgetOpco !== undefined) updateData.budgetOpco = rest.budgetOpco;
      if (rest.referenceOpco !== undefined) updateData.referenceOpco = rest.referenceOpco;
      if (rest.actif !== undefined) updateData.actif = rest.actif;

      await db.update(catalogueFormation).set(updateData).where(eq(catalogueFormation.id, id));
      return { success: true };
    }),

  /** Supprimer une formation du catalogue (admin uniquement) */
  delete: protectedProcedure
    .input(z.object({ id: z.number() }))
    .mutation(async ({ ctx, input }) => {
      if (!isAdmin(ctx.user.role)) {
        throw new TRPCError({ code: "FORBIDDEN", message: "Réservé aux administrateurs" });
      }
      const db = await getDb();
      if (!db) throw new TRPCError({ code: "INTERNAL_SERVER_ERROR", message: "DB non disponible" });
      await db.delete(catalogueFormation).where(eq(catalogueFormation.id, input.id));
      return { success: true };
    }),

  /** Qualifier une formation comme "Validée Itinova" (admin uniquement) */
  toggleValideeItinova: protectedProcedure
    .input(z.object({ id: z.number(), valeur: z.boolean() }))
    .mutation(async ({ ctx, input }) => {
      if (!isAdmin(ctx.user.role)) {
        throw new TRPCError({ code: "FORBIDDEN", message: "Réservé aux administrateurs" });
      }
      const db = await getDb();
      if (!db) throw new TRPCError({ code: "INTERNAL_SERVER_ERROR", message: "DB non disponible" });
      await db.update(catalogueFormation)
        .set({ validateeItinova: input.valeur })
        .where(eq(catalogueFormation.id, input.id));
      return { success: true };
    }),

  /** Importer des formations depuis un CSV/Excel (admin uniquement) */
  importBulk: protectedProcedure
    .input(
      z.object({
        formations: z.array(
          z.object({
            intitule: z.string().min(1),
            theme: z.string().optional(),
            motsCles: z.string().optional(),
            duree: z.string().optional(),
            prestataire: z.string().optional(),
            description: z.string().optional(),
            objectifs: z.string().optional(),
            publicConcerne: z.string().optional(),
            opcoEligible: z.boolean().optional(),
            budgetOpco: z.string().optional(),
            referenceOpco: z.string().optional(),
          })
        ),
        source: z.string().optional(),
      })
    )
    .mutation(async ({ ctx, input }) => {
      if (!isAdmin(ctx.user.role)) {
        throw new TRPCError({ code: "FORBIDDEN", message: "Réservé aux administrateurs" });
      }
      const db = await getDb();
      if (!db) throw new TRPCError({ code: "INTERNAL_SERVER_ERROR", message: "DB non disponible" });

      let inserted = 0;
      for (const f of input.formations) {
        await db.insert(catalogueFormation).values({
          intitule: f.intitule,
          theme: f.theme ?? null,
          motsCles: f.motsCles ?? null,
          duree: f.duree ?? null,
          prestataire: f.prestataire ?? null,
          description: f.description ?? null,
          objectifs: f.objectifs ?? null,
          publicConcerne: f.publicConcerne ?? null,
          validateeItinova: false,
          opcoEligible: f.opcoEligible ?? false,
          budgetOpco: f.budgetOpco ?? null,
          referenceOpco: f.referenceOpco ?? null,
          source: input.source ?? "import",
          actif: true,
        });
        inserted++;
      }

      return { success: true, inserted };
    }),

  /** Suggestion automatique : trouver les formations correspondant à un intitulé/thème */
  suggest: protectedProcedure
    .input(
      z.object({
        intitule: z.string(),
        theme: z.string().optional(),
        motsCles: z.string().optional(),
      })
    )
    .query(async ({ input }) => {
      const db = await getDb();
      if (!db) throw new TRPCError({ code: "INTERNAL_SERVER_ERROR", message: "DB non disponible" });

      const allFormations = await db.select().from(catalogueFormation).where(eq(catalogueFormation.actif, true));

      const searchTerms = [
        input.intitule.toLowerCase(),
        ...(input.theme ? [input.theme.toLowerCase()] : []),
        ...(input.motsCles ? input.motsCles.toLowerCase().split(",").map(k => k.trim()) : []),
      ].filter(Boolean);

      function scoreFormation(f: typeof allFormations[0]): number {
        let score = 0;
        const haystack = [
          f.intitule,
          f.theme ?? "",
          f.motsCles ?? "",
          f.description ?? "",
        ].join(" ").toLowerCase();

        for (const term of searchTerms) {
          if (haystack.includes(term)) score += 2;
          // Correspondance partielle (au moins 4 caractères)
          if (term.length >= 4) {
            const words = haystack.split(/\s+/);
            for (const word of words) {
              if (word.startsWith(term.substring(0, 4))) score += 1;
            }
          }
        }
        // Bonus si validée Itinova
        if (f.validateeItinova) score += 5;
        return score;
      }

      const scored = allFormations
        .map(f => ({ ...f, _score: scoreFormation(f) }))
        .filter(f => f._score > 0)
        .sort((a, b) => b._score - a._score)
        .slice(0, 10);

      // Séparer validées Itinova des autres
      const validateesItinova = scored.filter(f => f.validateeItinova);
      const autres = scored.filter(f => !f.validateeItinova);

      return { validateesItinova, autres };
    }),

  /** Lister les thèmes distincts du catalogue */
  themes: protectedProcedure.query(async () => {
    const db = await getDb();
    if (!db) throw new TRPCError({ code: "INTERNAL_SERVER_ERROR", message: "DB non disponible" });
    const rows = await db.select({ theme: catalogueFormation.theme }).from(catalogueFormation);
    const themes = [...new Set(rows.map(r => r.theme).filter(Boolean))] as string[];
    return themes.sort();
  }),
});