import {
  Body,
  Controller,
  Get,
  Param,
  Patch,
  Post,
  Query,
  Req,
  UnauthorizedException,
  UseGuards,
} from '@nestjs/common';
import { ApiTags, ApiOperation, ApiBearerAuth } from '@nestjs/swagger';
import { IsPublic } from '@tria-plc/api-common/modules/auth/decorators/public.decorator';
import { SupportService } from './support.service';
import { JwtGuard } from '../../common/jwt.guard';
import {
  CreateConversationDto,
  CreateGuestConversationDto,
  DeviceIdBodyDto,
  DeviceSendMessageDto,
  GuestIdBodyDto,
  GuestSendMessageDto,
  ListConversationsQueryDto,
  SendMessageDto,
  UpdateStatusDto,
} from './support.dto';

function userId(req: any): string {
  const id = req?.user?.id ?? req?.user?.sub;
  if (!id) throw new UnauthorizedException();
  return id;
}

@ApiTags('Support')
@Controller('support')
export class SupportController {
  constructor(private service: SupportService) {}

  // ---- FAQ (public) ------------------------------------------------------

  @Get('faq')
  @IsPublic()
  @ApiOperation({ summary: 'Get FAQ categories' })
  getFaqCategories() {
    return this.service.getFaqCategories();
  }

  @Get('faq/:categoryId/articles')
  @IsPublic()
  @ApiOperation({ summary: 'Get FAQ articles for a category' })
  getFaqArticles(@Param('categoryId') id: string) {
    return this.service.getFaqArticles(id);
  }

  // ---- customer: authenticated passenger --------------------------------

  @Post('conversations')
  @UseGuards(JwtGuard)
  @ApiBearerAuth('JWT-auth')
  @ApiOperation({ summary: 'Open a new support conversation' })
  createConversation(@Req() req: any, @Body() body: CreateConversationDto) {
    return this.service.createConversation(userId(req), body);
  }

  @Get('conversations')
  @UseGuards(JwtGuard)
  @ApiBearerAuth('JWT-auth')
  @ApiOperation({ summary: 'List my support conversations' })
  listMine(@Req() req: any, @Query() query: ListConversationsQueryDto) {
    return this.service.listForCustomer({ iamUserId: userId(req) }, query);
  }

  @Get('conversations/:id/messages')
  @UseGuards(JwtGuard)
  @ApiBearerAuth('JWT-auth')
  @ApiOperation({ summary: 'List messages in one of my conversations' })
  messages(@Req() req: any, @Param('id') id: string) {
    return this.service.getMessages(id, { iamUserId: userId(req) });
  }

  @Post('conversations/:id/messages')
  @UseGuards(JwtGuard)
  @ApiBearerAuth('JWT-auth')
  @ApiOperation({ summary: 'Send a message as the customer' })
  send(@Req() req: any, @Param('id') id: string, @Body() body: SendMessageDto) {
    return this.service.sendMessage(id, 'USER', body.text, {
      iamUserId: userId(req),
    });
  }

  @Post('conversations/:id/read')
  @UseGuards(JwtGuard)
  @ApiBearerAuth('JWT-auth')
  @ApiOperation({ summary: 'Mark a conversation read (customer side)' })
  read(@Req() req: any, @Param('id') id: string) {
    return this.service.markRead(id, 'USER', { iamUserId: userId(req) });
  }

  @Get('unread-count')
  @UseGuards(JwtGuard)
  @ApiBearerAuth('JWT-auth')
  @ApiOperation({ summary: 'Count my unread support conversations' })
  unread(@Req() req: any) {
    return this.service.unreadCount('USER', { iamUserId: userId(req) });
  }

  // ---- customer: device-scoped single thread (portal) -------------------
  // No auth, no forms. One conversation per device id (localStorage). Anyone
  // with the device id can see that thread — accepted MVP trade-off.

  @Get('device/thread')
  @IsPublic()
  @ApiOperation({ summary: "Get the device's support thread + messages" })
  deviceThread(@Query('deviceId') deviceId: string) {
    return this.service.getDeviceThread(deviceId);
  }

  @Post('device/messages')
  @IsPublic()
  @ApiOperation({ summary: 'Send a message (creates the thread on first send)' })
  deviceSend(@Body() body: DeviceSendMessageDto) {
    return this.service.sendDeviceMessage(body.deviceId, body.text);
  }

  @Post('device/read')
  @IsPublic()
  @ApiOperation({ summary: 'Mark the device thread read' })
  deviceRead(@Body() body: DeviceIdBodyDto) {
    return this.service.markDeviceRead(body.deviceId);
  }

  @Get('device/unread-count')
  @IsPublic()
  @ApiOperation({ summary: "Count the device thread's unread messages" })
  deviceUnread(@Query('deviceId') deviceId: string) {
    return this.service.unreadCount('USER', { guestId: deviceId });
  }

  // ---- customer: guest (unauthenticated, multi-ticket) ------------------
  // No JwtGuard. Access is scoped by a client-generated `guestId` (the bearer
  // of access — anyone with it sees that thread; accepted MVP trade-off).

  @Post('guest/conversations')
  @IsPublic()
  @ApiOperation({ summary: 'Open a support conversation as a guest' })
  guestCreate(@Body() body: CreateGuestConversationDto) {
    return this.service.createGuestConversation(body);
  }

  @Get('guest/conversations')
  @IsPublic()
  @ApiOperation({ summary: 'List a guest\'s conversations' })
  guestList(
    @Query('guestId') guestId: string,
    @Query() query: ListConversationsQueryDto,
  ) {
    return this.service.listForCustomer({ guestId }, query);
  }

  @Get('guest/conversations/:id/messages')
  @IsPublic()
  @ApiOperation({ summary: 'List messages in a guest conversation' })
  guestMessages(@Param('id') id: string, @Query('guestId') guestId: string) {
    return this.service.getMessages(id, { guestId });
  }

  @Post('guest/conversations/:id/messages')
  @IsPublic()
  @ApiOperation({ summary: 'Send a message as a guest' })
  guestSend(@Param('id') id: string, @Body() body: GuestSendMessageDto) {
    return this.service.sendMessage(id, 'USER', body.text, {
      guestId: body.guestId,
    });
  }

  @Post('guest/conversations/:id/read')
  @IsPublic()
  @ApiOperation({ summary: 'Mark a guest conversation read' })
  guestRead(@Param('id') id: string, @Body() body: GuestIdBodyDto) {
    return this.service.markRead(id, 'USER', { guestId: body.guestId });
  }

  @Get('guest/unread-count')
  @IsPublic()
  @ApiOperation({ summary: 'Count a guest\'s unread conversations' })
  guestUnread(@Query('guestId') guestId: string) {
    return this.service.unreadCount('USER', { guestId });
  }

  // ---- agent (backoffice) ------------------------------------------------
  // TODO: gate agent routes with a staff permission once passenger RBAC is wired.

  @Get('agent/conversations')
  @UseGuards(JwtGuard)
  @ApiBearerAuth('JWT-auth')
  @ApiOperation({ summary: 'List all support conversations (shared inbox)' })
  agentList(@Query() query: ListConversationsQueryDto) {
    return this.service.listForAgents(query);
  }

  @Get('agent/conversations/:id/messages')
  @UseGuards(JwtGuard)
  @ApiBearerAuth('JWT-auth')
  @ApiOperation({ summary: 'List messages in a conversation' })
  agentMessages(@Param('id') id: string) {
    return this.service.getMessages(id);
  }

  @Post('agent/conversations/:id/messages')
  @UseGuards(JwtGuard)
  @ApiBearerAuth('JWT-auth')
  @ApiOperation({ summary: 'Reply as an agent' })
  agentSend(@Param('id') id: string, @Body() body: SendMessageDto) {
    return this.service.sendMessage(id, 'AGENT', body.text);
  }

  @Patch('agent/conversations/:id/status')
  @UseGuards(JwtGuard)
  @ApiBearerAuth('JWT-auth')
  @ApiOperation({ summary: "Change a conversation's status" })
  agentStatus(@Param('id') id: string, @Body() body: UpdateStatusDto) {
    return this.service.setStatus(id, body.status);
  }

  @Post('agent/conversations/:id/read')
  @UseGuards(JwtGuard)
  @ApiBearerAuth('JWT-auth')
  @ApiOperation({ summary: 'Mark a conversation read (agent side)' })
  agentRead(@Param('id') id: string) {
    return this.service.markRead(id, 'AGENT');
  }

  @Get('agent/unread-count')
  @UseGuards(JwtGuard)
  @ApiBearerAuth('JWT-auth')
  @ApiOperation({ summary: 'Count unread conversations (agent side)' })
  agentUnread() {
    return this.service.unreadCount('AGENT');
  }
}