import { TRPCError } from '@trpc/server';
import { and, eq, inArray } from 'drizzle-orm';
import { z } from 'zod';
import { schema } from '@linkder/db';
import { assertTransition, credentialSchema, proProfileSchema } from '@linkder/shared';
import { protectedProcedure, proProcedure, router } from '../trpc';

/**
 * A pro is only shown to clients once verification passes. These procedures
 * cover everything up to that point: building the profile, uploading documents,
 * and submitting for review. None of them require `verified` — that would make
 * onboarding impossible.
 */
export const proRouter = router({
  /** The caller's own pro profile, with everything the onboarding wizard needs. */
  me: proProcedure.query(async ({ ctx }) => {
    const profile = await ctx.db.query.proProfiles.findFirst({
      where: eq(schema.proProfiles.userId, ctx.session.userId),
    });
    if (!profile) return null;

    const [categories, media, credentials] = await Promise.all([
      ctx.db
        .select({ categoryId: schema.proCategories.categoryId })
        .from(schema.proCategories)
        .where(eq(schema.proCategories.proId, ctx.session.userId)),
      ctx.db
        .select()
        .from(schema.proMedia)
        .where(eq(schema.proMedia.proId, ctx.session.userId))
        .orderBy(schema.proMedia.position),
      ctx.db
        .select()
        .from(schema.credentials)
        .where(eq(schema.credentials.proId, ctx.session.userId)),
    ]);

    return {
      ...profile,
      categoryIds: categories.map((c) => c.categoryId),
      media,
      credentials,
    };
  }),

  /**
   * Create or replace the profile. Idempotent so the wizard can save on every
   * step without the client tracking whether a row exists yet.
   */
  upsertProfile: proProcedure.input(proProfileSchema).mutation(async ({ ctx, input }) => {
    const validCategories = await ctx.db
      .select({ id: schema.categories.id })
      .from(schema.categories)
      .where(
        and(
          inArray(schema.categories.id, input.categoryIds),
          eq(schema.categories.isActive, true),
        ),
      );
    if (validCategories.length !== input.categoryIds.length) {
      throw new TRPCError({ code: 'BAD_REQUEST', message: 'One of those trades is not available' });
    }

    const existing = await ctx.db.query.proProfiles.findFirst({
      where: eq(schema.proProfiles.userId, ctx.session.userId),
    });

    // Editing a live profile sends it back for review — a verified plumber must
    // not be able to quietly become an unverified electrician.
    const materiallyChanged =
      existing &&
      (existing.serviceRadiusM !== input.serviceRadiusM ||
        existing.baseLocation.lat !== input.location.lat ||
        existing.baseLocation.lng !== input.location.lng);

    await ctx.db.transaction(async (tx) => {
      const values = {
        userId: ctx.session.userId,
        headline: input.headline,
        bio: input.bio,
        hourlyRateCents: input.hourlyRateCents,
        yearsExperience: input.yearsExperience,
        baseLocation: input.location,
        serviceRadiusM: input.serviceRadiusM,
        updatedAt: new Date(),
      };

      await tx
        .insert(schema.proProfiles)
        .values(values)
        .onConflictDoUpdate({ target: schema.proProfiles.userId, set: values });

      await tx
        .delete(schema.proCategories)
        .where(eq(schema.proCategories.proId, ctx.session.userId));
      await tx.insert(schema.proCategories).values(
        input.categoryIds.map((categoryId) => ({ proId: ctx.session.userId, categoryId })),
      );
    });

    return { saved: true, requiresReReview: Boolean(materiallyChanged) };
  }),

  /** Attach an uploaded photo. The file itself went straight to R2. */
  addMedia: proProcedure
    .input(
      z.object({
        url: z.string().url(),
        kind: z.enum(['photo', 'work_sample']).default('photo'),
        position: z.number().int().min(0).max(20).optional(),
      }),
    )
    .mutation(async ({ ctx, input }) => {
      const existing = await ctx.db
        .select()
        .from(schema.proMedia)
        .where(eq(schema.proMedia.proId, ctx.session.userId));
      if (existing.length >= 10) {
        throw new TRPCError({ code: 'BAD_REQUEST', message: 'You can have at most 10 photos' });
      }

      const [media] = await ctx.db
        .insert(schema.proMedia)
        .values({
          proId: ctx.session.userId,
          url: input.url,
          kind: input.kind,
          position: input.position ?? existing.length,
        })
        .returning();
      return media;
    }),

  removeMedia: proProcedure
    .input(z.object({ id: z.string().uuid() }))
    .mutation(async ({ ctx, input }) => {
      // Scoped to the caller so one pro cannot delete another's photo.
      const deleted = await ctx.db
        .delete(schema.proMedia)
        .where(and(eq(schema.proMedia.id, input.id), eq(schema.proMedia.proId, ctx.session.userId)))
        .returning();
      if (deleted.length === 0) throw new TRPCError({ code: 'NOT_FOUND' });
      return { removed: true };
    }),

  /** Upload a licence, insurance certificate or ID document for review. */
  addCredential: proProcedure.input(credentialSchema).mutation(async ({ ctx, input }) => {
    const [credential] = await ctx.db
      .insert(schema.credentials)
      .values({
        proId: ctx.session.userId,
        kind: input.kind,
        fileUrl: input.fileUrl,
        issuer: input.issuer ?? null,
        expiresAt: input.expiresAt ?? null,
      })
      .returning();
    return credential;
  }),

  /**
   * Submit for review. Deliberately strict about what "complete" means — a
   * half-finished profile reaching the admin queue wastes a reviewer's time,
   * and the reviewer is the expensive part of this pipeline.
   */
  submitForReview: proProcedure.mutation(async ({ ctx }) => {
    const profile = await ctx.db.query.proProfiles.findFirst({
      where: eq(schema.proProfiles.userId, ctx.session.userId),
    });
    if (!profile) {
      throw new TRPCError({ code: 'PRECONDITION_FAILED', message: 'Fill in your profile first' });
    }

    const [categories, media, credentials] = await Promise.all([
      ctx.db
        .select()
        .from(schema.proCategories)
        .where(eq(schema.proCategories.proId, ctx.session.userId)),
      ctx.db.select().from(schema.proMedia).where(eq(schema.proMedia.proId, ctx.session.userId)),
      ctx.db
        .select()
        .from(schema.credentials)
        .where(eq(schema.credentials.proId, ctx.session.userId)),
    ]);

    const missing: string[] = [];
    if (categories.length === 0) missing.push('at least one trade');
    if (media.length === 0) missing.push('at least one photo');
    if (!credentials.some((c) => c.kind === 'id')) missing.push('a photo ID');
    if (!credentials.some((c) => c.kind === 'insurance')) missing.push('proof of insurance');

    if (missing.length) {
      throw new TRPCError({
        code: 'PRECONDITION_FAILED',
        message: `Before we can review your account we still need: ${missing.join(', ')}.`,
      });
    }

    assertTransition('verification', profile.verificationStatus, 'pending');

    await ctx.db
      .update(schema.proProfiles)
      .set({ verificationStatus: 'pending', updatedAt: new Date() })
      .where(eq(schema.proProfiles.userId, ctx.session.userId));

    await ctx.db.insert(schema.auditLog).values({
      actorId: ctx.session.userId,
      action: 'verification.submitted',
      entity: 'pro_profile',
      entityId: ctx.session.userId,
      ip: ctx.ip,
    });

    // TODO(M2): kick off the Didit identity session and notify the admin queue.

    return { status: 'pending' as const };
  }),

  /** Holiday mode. Keeps a verified pro off the deck without unverifying them. */
  setAcceptingJobs: proProcedure
    .input(z.object({ accepting: z.boolean() }))
    .mutation(async ({ ctx, input }) => {
      await ctx.db
        .update(schema.proProfiles)
        .set({ isAcceptingJobs: input.accepting, updatedAt: new Date() })
        .where(eq(schema.proProfiles.userId, ctx.session.userId));
      return { accepting: input.accepting };
    }),

  /**
   * Public profile, for the card detail view. Only ever returns a verified pro,
   * and deliberately omits anything private — no phone, no documents, no address.
   */
  publicProfile: protectedProcedure
    .input(z.object({ proId: z.string().uuid() }))
    .query(async ({ ctx, input }) => {
      const profile = await ctx.db.query.proProfiles.findFirst({
        where: and(
          eq(schema.proProfiles.userId, input.proId),
          eq(schema.proProfiles.verificationStatus, 'verified'),
        ),
      });
      if (!profile) throw new TRPCError({ code: 'NOT_FOUND' });

      const [user] = await ctx.db
        .select({ name: schema.users.name, image: schema.users.image })
        .from(schema.users)
        .where(eq(schema.users.id, input.proId));

      const media = await ctx.db
        .select()
        .from(schema.proMedia)
        .where(eq(schema.proMedia.proId, input.proId))
        .orderBy(schema.proMedia.position);

      return {
        proId: profile.userId,
        name: user?.name ?? null,
        image: user?.image ?? null,
        headline: profile.headline,
        bio: profile.bio,
        hourlyRateCents: profile.hourlyRateCents,
        yearsExperience: profile.yearsExperience,
        ratingAvg: profile.ratingAvg === null ? null : Number(profile.ratingAvg),
        ratingCount: profile.ratingCount,
        completedJobs: profile.completedJobs,
        media,
      };
    }),
});