import { Router, Request, Response, NextFunction } from 'express';
import { z } from 'zod';
import { InboxStatus, MailboxAuthType, MailboxProvider, MailboxRole } from '../lib/prisma';
import { prisma } from '../lib/prisma';
import { encrypt } from '../services/crypto.service';
import { testConnection } from '../services/email.service';
import { isMicrosoftConsumerEmail } from '../services/microsoft-oauth.service';
import { stripPassword } from '../lib/inboxGuard';
import { AppError } from '../middleware/errorHandler';
import { applyProviderPreset, PROVIDER_PRESETS } from '../models/provider-presets';
import { checkMailboxDns } from '../lib/dns-check';
import { resolveWorkspaceId } from '../services/workspace.service';

const router = Router();

const createInboxSchema = z.object({
  email: z.string().email(),
  smtpHost: z.string().min(1).optional(),
  smtpPort: z.coerce.number().int().positive().optional(),
  imapHost: z.string().min(1).optional(),
  imapPort: z.coerce.number().int().positive().optional(),
  username: z.string().min(1),
  password: z.string().optional(),
  authType: z.nativeEnum(MailboxAuthType).optional(),
  oauthRefreshToken: z.string().optional(),
  workspaceId: z.string().optional(),
  role: z.nativeEnum(MailboxRole).optional(),
  provider: z.nativeEnum(MailboxProvider).default(MailboxProvider.custom),
  dailyLimit: z.coerce.number().int().positive().optional(),
  currentRamp: z.coerce.number().int().positive().optional(),
  industry: z.string().min(1).optional(),
  senderName: z.string().optional(),
  companyName: z.string().optional(),
  status: z.nativeEnum(InboxStatus).optional(),
});

const updateInboxSchema = z.object({
  email: z.string().email().optional(),
  smtpHost: z.string().min(1).optional(),
  smtpPort: z.coerce.number().int().positive().optional(),
  imapHost: z.string().min(1).optional(),
  imapPort: z.coerce.number().int().positive().optional(),
  username: z.string().min(1).optional(),
  password: z.string().optional(),
  authType: z.nativeEnum(MailboxAuthType).optional(),
  oauthRefreshToken: z.string().optional(),
  role: z.nativeEnum(MailboxRole).optional(),
  provider: z.nativeEnum(MailboxProvider).optional(),
  dailyLimit: z.coerce.number().int().positive().optional(),
  currentRamp: z.coerce.number().int().positive().optional(),
  industry: z.string().min(1).optional(),
  senderName: z.string().optional(),
  companyName: z.string().optional(),
  status: z.nativeEnum(InboxStatus).optional(),
});

const listQuerySchema = z.object({
  role: z.nativeEnum(MailboxRole).optional(),
  workspaceId: z.string().optional(),
});

router.get('/provider-presets', (_req: Request, res: Response) => {
  res.json(PROVIDER_PRESETS);
});

function resolveAuthType(
  data: z.infer<typeof createInboxSchema>,
  provider: MailboxProvider,
): MailboxAuthType {
  if (data.authType) return data.authType;
  if (provider === MailboxProvider.outlook && data.oauthRefreshToken) {
    return MailboxAuthType.microsoft_oauth;
  }
  return MailboxAuthType.password;
}

async function validateRoleChange(inboxId: string, newRole: MailboxRole): Promise<void> {
  const inbox = await prisma.inbox.findUnique({ where: { id: inboxId } });
  if (!inbox) throw new AppError(404, 'Inbox not found');

  if (newRole === inbox.role) return;

  if (newRole === MailboxRole.primary) {
    throw new AppError(400, 'Set a mailbox as primary by creating or editing a campaign');
  }

  if (inbox.role === MailboxRole.primary) {
    const activeCampaign = await prisma.warmupCampaign.findFirst({
      where: {
        primaryMailboxId: inboxId,
        status: { in: ['active', 'maintenance', 'paused'] },
      },
    });
    if (activeCampaign) {
      throw new AppError(400, 'Cannot change role while this mailbox is a campaign primary');
    }
  }

  if (newRole === MailboxRole.unassigned && inbox.role === MailboxRole.satellite) {
    const assignments = await prisma.campaignSatellite.count({
      where: { satelliteMailboxId: inboxId },
    });
    if (assignments > 0) {
      throw new AppError(
        400,
        'Remove this mailbox from all campaigns before setting role to unassigned',
      );
    }
  }
}

router.post('/', async (req: Request, res: Response, next: NextFunction) => {
  try {
    const data = createInboxSchema.parse(req.body);
    const workspaceId = await resolveWorkspaceId(data.workspaceId);
    const provider = data.provider ?? MailboxProvider.custom;
    const authType = resolveAuthType(data, provider);

    if (authType === MailboxAuthType.password && !data.password) {
      throw new AppError(400, 'Password is required for password authentication');
    }
    if (authType === MailboxAuthType.microsoft_oauth && !data.oauthRefreshToken) {
      throw new AppError(
        400,
        'Microsoft OAuth is required for @live.com/@outlook.com accounts. Use Connect Microsoft.',
      );
    }

    const presetFields = applyProviderPreset(provider, {
      smtpHost: data.smtpHost,
      smtpPort: data.smtpPort,
      imapHost: data.imapHost,
      imapPort: data.imapPort,
    });

    if (!presetFields.smtpHost || !presetFields.imapHost || !presetFields.smtpPort || !presetFields.imapPort) {
      throw new AppError(400, 'smtpHost, smtpPort, imapHost, and imapPort are required for custom provider');
    }

    if (
      authType === MailboxAuthType.password &&
      provider === MailboxProvider.outlook &&
      isMicrosoftConsumerEmail(data.email)
    ) {
      throw new AppError(
        400,
        'Microsoft consumer accounts (@live.com, @outlook.com) require OAuth. Use Connect Microsoft instead of an app password.',
      );
    }

    const candidate = {
      id: 'test',
      workspaceId,
      email: data.email,
      smtpHost: presetFields.smtpHost,
      smtpPort: presetFields.smtpPort,
      imapHost: presetFields.imapHost,
      imapPort: presetFields.imapPort,
      username: data.username,
      password: encrypt(data.password ?? 'oauth-placeholder'),
      authType,
      oauthRefreshToken: data.oauthRefreshToken ? encrypt(data.oauthRefreshToken) : null,
      role: data.role ?? MailboxRole.unassigned,
      provider,
      status: InboxStatus.active,
      dailyLimit: data.dailyLimit ?? 40,
      currentRamp: data.currentRamp ?? 5,
      industry: data.industry ?? 'SaaS',
      senderName: data.senderName ?? null,
      companyName: data.companyName ?? null,
      lastError: null,
      errorAt: null,
      consecutiveFailures: 0,
      spamFolderPath: null,
      lastSpamRescuedAt: null,
      createdAt: new Date(),
      updatedAt: new Date(),
    };

    const connection = await testConnection(candidate);
    if (!connection.smtp.ok || !connection.imap.ok) {
      const errors = [
        !connection.smtp.ok ? `SMTP: ${connection.smtp.error}` : null,
        !connection.imap.ok ? `IMAP: ${connection.imap.error}` : null,
      ].filter(Boolean);
      throw new AppError(400, `Connection test failed. ${errors.join(' ')}`);
    }

    const inbox = await prisma.inbox.create({
      data: {
        workspaceId,
        email: data.email,
        smtpHost: presetFields.smtpHost,
        smtpPort: presetFields.smtpPort,
        imapHost: presetFields.imapHost,
        imapPort: presetFields.imapPort,
        username: data.username,
        password: encrypt(data.password ?? 'oauth-placeholder'),
        authType,
        oauthRefreshToken: data.oauthRefreshToken ? encrypt(data.oauthRefreshToken) : null,
        role: data.role ?? MailboxRole.unassigned,
        provider,
        dailyLimit: data.dailyLimit ?? 40,
        currentRamp: data.currentRamp ?? 5,
        industry: data.industry ?? 'SaaS',
        senderName: data.senderName,
        companyName: data.companyName,
        status: InboxStatus.active,
      },
    });
    res.status(201).json(stripPassword(inbox));
  } catch (err) {
    next(err);
  }
});

router.get('/', async (req: Request, res: Response, next: NextFunction) => {
  try {
    const { role, workspaceId: wsId } = listQuerySchema.parse(req.query);
    const workspaceId = wsId ? await resolveWorkspaceId(wsId) : undefined;

    const inboxes = await prisma.inbox.findMany({
      where: {
        ...(role ? { role } : {}),
        ...(workspaceId ? { workspaceId } : {}),
      },
      orderBy: { createdAt: 'desc' },
    });
    res.json(inboxes.map(stripPassword));
  } catch (err) {
    next(err);
  }
});

router.get('/:id', async (req: Request, res: Response, next: NextFunction) => {
  try {
    const inbox = await prisma.inbox.findUnique({ where: { id: req.params.id } });
    if (!inbox) {
      throw new AppError(404, 'Inbox not found');
    }
    res.json(stripPassword(inbox));
  } catch (err) {
    next(err);
  }
});

router.patch('/:id', async (req: Request, res: Response, next: NextFunction) => {
  try {
    const data = updateInboxSchema.parse(req.body);
    const { password, provider, oauthRefreshToken, role, authType, ...rest } = data;

    if (role) {
      await validateRoleChange(req.params.id, role);
    }

    let connectionUpdates = {};
    if (provider) {
      connectionUpdates = applyProviderPreset(provider, {
        smtpHost: data.smtpHost,
        smtpPort: data.smtpPort,
        imapHost: data.imapHost,
        imapPort: data.imapPort,
      });
    }

    const existing = await prisma.inbox.findUnique({ where: { id: req.params.id } });
    if (!existing) throw new AppError(404, 'Inbox not found');

    const nextAuthType = authType ?? existing.authType;
    const nextPassword = password ? encrypt(password) : existing.password;
    const nextOAuth = oauthRefreshToken ? encrypt(oauthRefreshToken) : existing.oauthRefreshToken;

    if (password || oauthRefreshToken || authType || provider) {
      const candidate = {
        ...existing,
        ...rest,
        ...(provider ? { provider } : {}),
        ...connectionUpdates,
        password: nextPassword,
        authType: nextAuthType,
        oauthRefreshToken: nextOAuth,
      };
      const connection = await testConnection(candidate);
      if (!connection.smtp.ok || !connection.imap.ok) {
        const errors = [
          !connection.smtp.ok ? `SMTP: ${connection.smtp.error}` : null,
          !connection.imap.ok ? `IMAP: ${connection.imap.error}` : null,
        ].filter(Boolean);
        throw new AppError(400, `Connection test failed. ${errors.join(' ')}`);
      }
    }

    const inbox = await prisma.inbox.update({
      where: { id: req.params.id },
      data: {
        ...rest,
        ...(role ? { role } : {}),
        ...(provider ? { provider } : {}),
        ...(authType ? { authType } : {}),
        ...connectionUpdates,
        ...(password ? { password: encrypt(password) } : {}),
        ...(oauthRefreshToken ? { oauthRefreshToken: encrypt(oauthRefreshToken) } : {}),
        ...(rest.status === InboxStatus.active
          ? { lastError: null, errorAt: null, consecutiveFailures: 0 }
          : {}),
      },
    });
    res.json(stripPassword(inbox));
  } catch (err) {
    next(err);
  }
});

router.delete('/:id', async (req: Request, res: Response, next: NextFunction) => {
  try {
    await prisma.inbox.delete({ where: { id: req.params.id } });
    res.status(204).send();
  } catch (err) {
    next(err);
  }
});

router.post('/:id/dns-check', async (req: Request, res: Response, next: NextFunction) => {
  try {
    const inbox = await prisma.inbox.findUnique({ where: { id: req.params.id } });
    if (!inbox) {
      throw new AppError(404, 'Inbox not found');
    }
    const result = await checkMailboxDns(inbox.email);
    res.json(result);
  } catch (err) {
    next(err);
  }
});

router.post('/:id/test', async (req: Request, res: Response, next: NextFunction) => {
  try {
    const inbox = await prisma.inbox.findUnique({ where: { id: req.params.id } });
    if (!inbox) {
      throw new AppError(404, 'Inbox not found');
    }

    const result = await testConnection(inbox);
    const ok = result.smtp.ok && result.imap.ok;

    if (!ok) {
      await prisma.inbox.update({
        where: { id: inbox.id },
        data: {
          status: InboxStatus.error,
          lastError: result.smtp.error ?? result.imap.error ?? 'Connection test failed',
          errorAt: new Date(),
        },
      });
    } else {
      await prisma.inbox.update({
        where: { id: inbox.id },
        data: {
          status: InboxStatus.active,
          lastError: null,
          errorAt: null,
          consecutiveFailures: 0,
        },
      });
    }

    res.json({ ok, ...result });
  } catch (err) {
    next(err);
  }
});

export default router;