import { Body, Controller, Delete, Get, Param, Post, Req, UseGuards } from '@nestjs/common';
import { AuthGuard } from '@nestjs/passport';
import { ChatService } from './chat.service';
import { ChatGateway } from './chat.gateway';
import { CreateChannelDto } from './dto/create-channel.dto';
import { CreateDirectChannelDto } from './dto/create-direct-channel.dto';
import { AddParticipantDto } from './dto/add-participant.dto';
import { Roles } from '../common/roles.decorator';
import { RolesGuard } from '../common/roles.guard';
import { Role } from '../common/role.enum';
import { AuthenticatedRequest } from '../auth/authenticated-request';
import { GuestJwtPayload } from '../auth/guest-auth.service';
import { resolveChatCaller } from './caller.util';

type ChatRequest = AuthenticatedRequest & { user?: AuthenticatedRequest['user'] | GuestJwtPayload };

@Controller('chat')
export class ChatController {
  constructor(
    private readonly chat: ChatService,
    private readonly gateway: ChatGateway,
  ) {}

  /// Channel administration (Gemeinde-Gruppen, LT-Kanäle, Broadcasts) is Leitungsteam-only.
  @Post(':kcId/channels')
  @UseGuards(AuthGuard('authentik'), RolesGuard)
  @Roles(Role.LEITUNGSTEAM)
  createChannel(@Param('kcId') kcId: string, @Body() dto: CreateChannelDto) {
    return this.chat.createChannel(kcId, dto.type, dto.gemeindeId);
  }

  /// Free-form group chat ("Gruppenchat"): a Leitungsteam member (any KC) or
  /// a Gemeinde Verantwortliche/r (their own KC, enforced by RolesGuard's
  /// kcId scoping) can create one and pick any mix of team users and Konfis
  /// (guests) from this KC as initial participants.
  @Post(':kcId/gruppen')
  @UseGuards(AuthGuard(['authentik', 'team']), RolesGuard)
  @Roles(Role.LEITUNGSTEAM, Role.GEMEINDE_VERANTWORTLICHER)
  createGruppe(
    @Param('kcId') kcId: string,
    @Body() dto: CreateChannelDto,
    @Req() req: AuthenticatedRequest,
  ) {
    return this.chat.createGruppe(kcId, dto.name, req.user!.userId, {
      userIds: dto.participantUserIds,
      guestIds: dto.participantGuestIds,
    });
  }

  /// Candidates (team users + Konfis) a caller may add to a Gruppenchat in
  /// this KC. Allowed for LT or a Verantwortliche/r of this KC.
  @Get(':kcId/gruppen/participant-candidates')
  @UseGuards(AuthGuard(['authentik', 'team']))
  listPossibleParticipants(@Param('kcId') kcId: string, @Req() req: AuthenticatedRequest) {
    return this.chat.listPossibleParticipants(kcId, req.user!);
  }

  /// Add a team user or Konfi to a Gruppenchat. Allowed for the channel's
  /// creator, any Leitungsteam member, or a Verantwortliche/r of that KC.
  @Post('gruppen/:channelId/participants')
  @UseGuards(AuthGuard(['authentik', 'team']))
  addParticipant(
    @Param('channelId') channelId: string,
    @Body() dto: AddParticipantDto,
    @Req() req: AuthenticatedRequest,
  ) {
    return this.chat
      .addParticipant(
        channelId,
        { kind: 'user', user: req.user! },
        { userId: dto.userId, guestId: dto.guestId },
      )
      .then((result) => {
        this.gateway.notifyParticipantsChanged(channelId);
        return result;
      });
  }

  /// Remove a team user or Konfi from a Gruppenchat. Same authorization as add.
  @Delete('gruppen/:channelId/participants')
  @UseGuards(AuthGuard(['authentik', 'team']))
  removeParticipant(
    @Param('channelId') channelId: string,
    @Body() dto: AddParticipantDto,
    @Req() req: AuthenticatedRequest,
  ) {
    return this.chat
      .removeParticipant(
        channelId,
        { kind: 'user', user: req.user! },
        { userId: dto.userId, guestId: dto.guestId },
      )
      .then((result) => {
        this.gateway.notifyParticipantsChanged(channelId);
        return result;
      });
  }

  /// Any two team members of the same KC can start a direct conversation
  /// (Authentik-backed members and local Gemeinde Teamer alike).
  @Post('direct')
  @UseGuards(AuthGuard(['authentik', 'team']))
  createDirectChannel(@Body() dto: CreateDirectChannelDto, @Req() req: AuthenticatedRequest) {
    return this.chat.getOrCreateDirectChannel(dto.kcId, req.user!.userId, dto.otherUserId);
  }

  @Get(':kcId/channels')
  @UseGuards(AuthGuard(['authentik', 'team', 'guest']))
  listChannels(@Param('kcId') kcId: string, @Req() req: ChatRequest) {
    return this.chat.listChannelsForCaller(kcId, resolveChatCaller(req.user!));
  }

  @Get('channels/:channelId/messages')
  @UseGuards(AuthGuard(['authentik', 'team', 'guest']))
  listMessages(@Param('channelId') channelId: string, @Req() req: ChatRequest) {
    return this.chat.listMessages(channelId, resolveChatCaller(req.user!));
  }
}