import {
	CreateSlackAgentAppDto,
	type CreateSlackAgentAppResponse,
	type CreateSlackManagerCredentialResponse,
	InstallSlackManagedAppDto,
	type InstallSlackManagedAppResponse,
	type SlackAgentAppManifestResponse,
	type SlackManagedAppSettings,
	type SlackManagedSetupState,
	UpdateSlackManagedAppSettingsDto,
} from '@n8n/api-types';
import type { AuthenticatedRequest } from '@n8n/db';
import { Body, Get, Param, Post, ProjectScope, RestController } from '@n8n/decorators';
import type { Request, Response } from 'express';

import { SlackManagedSetupService } from './integrations/platforms/slack/slack-managed-setup.service';
import { SlackManualSetupService } from './integrations/platforms/slack/slack-manual-setup.service';

@RestController('/projects/:projectId/agents/v2')
export class AgentSlackIntegrationsController {
	constructor(
		private readonly manualSetup: SlackManualSetupService,
		private readonly managedSetup: SlackManagedSetupService,
	) {}

	@Post('/:agentId/integrations/slack/app')
	@ProjectScope('agent:update')
	async createSlackApp(
		req: AuthenticatedRequest<{ projectId: string }>,
		_res: Response,
		@Param('agentId') agentId: string,
		@Body payload: CreateSlackAgentAppDto,
	): Promise<CreateSlackAgentAppResponse> {
		return await this.manualSetup.createApp({
			projectId: req.params.projectId,
			agentId,
			appConfigurationToken: payload.appConfigurationToken,
			user: req.user,
		});
	}

	@Get('/:agentId/integrations/slack/manifest')
	@ProjectScope('agent:read')
	async getSlackAppManifest(
		req: AuthenticatedRequest<{ projectId: string }>,
		_res: Response,
		@Param('agentId') agentId: string,
	): Promise<SlackAgentAppManifestResponse> {
		return await this.manualSetup.getManifest({ projectId: req.params.projectId, agentId });
	}

	@Get('/:agentId/integrations/slack/managed/setup')
	@ProjectScope('agent:read')
	async getManagedSlackSetup(
		req: AuthenticatedRequest<{ projectId: string }>,
		_res: Response,
		@Param('agentId') agentId: string,
	): Promise<SlackManagedSetupState> {
		return await this.managedSetup.getSetupState({
			projectId: req.params.projectId,
			agentId,
			user: req.user,
		});
	}

	@Post('/:agentId/integrations/slack/managed/credentials')
	@ProjectScope('agent:update')
	async createManagedSlackCredential(
		req: AuthenticatedRequest<{ projectId: string }>,
		_res: Response,
		@Param('agentId') agentId: string,
	): Promise<CreateSlackManagerCredentialResponse> {
		return await this.managedSetup.createManagerCredential({
			projectId: req.params.projectId,
			agentId,
			user: req.user,
		});
	}

	@Post('/:agentId/integrations/slack/managed/credentials/:credentialId/finalize')
	@ProjectScope('agent:update')
	async finalizeManagedSlackCredential(
		req: AuthenticatedRequest<{ projectId: string }>,
		_res: Response,
		@Param('agentId') agentId: string,
		@Param('credentialId') credentialId: string,
	): Promise<void> {
		await this.managedSetup.finalizeManagerCredential({
			projectId: req.params.projectId,
			agentId,
			credentialId,
			user: req.user,
		});
	}

	@Post('/:agentId/integrations/slack/managed/install')
	@ProjectScope('agent:update')
	async installManagedSlackApp(
		req: AuthenticatedRequest<{ projectId: string }>,
		_res: Response,
		@Param('agentId') agentId: string,
		@Body payload: InstallSlackManagedAppDto,
	): Promise<InstallSlackManagedAppResponse> {
		return await this.managedSetup.installApp({
			projectId: req.params.projectId,
			agentId,
			user: req.user,
			managerCredentialId: payload.managerCredentialId,
			workspaceId: payload.workspaceId,
		});
	}

	@Get('/:agentId/integrations/slack/managed/settings/:credentialId')
	@ProjectScope('agent:read')
	async getManagedSlackAppSettings(
		req: AuthenticatedRequest<{ projectId: string }>,
		_res: Response,
		@Param('agentId') agentId: string,
		@Param('credentialId') credentialId: string,
	): Promise<SlackManagedAppSettings> {
		return await this.managedSetup.getAppSettings({
			projectId: req.params.projectId,
			agentId,
			credentialId,
			user: req.user,
		});
	}

	@Post('/:agentId/integrations/slack/managed/settings')
	@ProjectScope('agent:update')
	async updateManagedSlackAppSettings(
		req: AuthenticatedRequest<{ projectId: string }>,
		_res: Response,
		@Param('agentId') agentId: string,
		@Body payload: UpdateSlackManagedAppSettingsDto,
	): Promise<SlackManagedAppSettings> {
		return await this.managedSetup.updateAppSettings({
			projectId: req.params.projectId,
			agentId,
			user: req.user,
			credentialId: payload.credentialId,
			name: payload.name,
			description: payload.description,
			alwaysOnline: payload.alwaysOnline,
		});
	}

	// Slack OAuth callback: authentication uses the encrypted one-time state
	// generated by the authenticated createSlackApp route.
	@Get('/:agentId/integrations/slack/oauth/callback', { skipAuth: true, usesTemplates: true })
	async handleSlackAppOAuthCallback(
		req: Request<
			{ projectId: string; agentId: string },
			unknown,
			unknown,
			{ code?: string; state?: string; error?: string; error_description?: string }
		>,
		res: Response,
		@Param('agentId') agentId: string,
	) {
		const { code, state, error, error_description: errorDescription } = req.query;
		if (error) {
			return res.render('oauth-error-callback', {
				error: { message: error, ...(errorDescription ? { reason: errorDescription } : {}) },
			});
		}
		if (!code || !state) {
			return res.render('oauth-error-callback', {
				error: { message: 'Insufficient parameters for Slack app setup callback.' },
			});
		}

		try {
			await this.manualSetup.completeInstall({
				projectId: req.params.projectId,
				agentId,
				code,
				state,
			});
			return res.render('oauth-callback');
		} catch (callbackError) {
			return res.render('oauth-error-callback', {
				error: {
					message:
						callbackError instanceof Error ? callbackError.message : 'Slack app setup failed',
				},
			});
		}
	}
}