import {
  Body,
  Controller,
  Delete,
  Get,
  HttpCode,
  Param,
  ParseUUIDPipe,
  Patch,
  Post,
  Put,
  Query,
} from '@nestjs/common';
import {
  ApiCreatedResponse,
  ApiOkResponse,
  ApiOperation,
  ApiParam,
  ApiTags,
} from '@nestjs/swagger';
import { User } from '@task-stream/api/identity/domain';
import {
  ApiOptionalPireonAuth,
  ApiPireonAuth,
  CurrentUser,
} from '@task-stream/api/identity/presenters';
import {
  ApiCommandErrors,
  ApiReadErrors,
} from '@task-stream/api/shared/presenters';
import {
  CommentsService,
  IssuesService,
} from '@task-stream/api/tracker/application';
import { IssueLinkType } from '@task-stream/api/tracker/domain';
import { withoutNulls } from '../common/issue-input';
import {
  AssignIssueDto,
  BulkUpdateIssuesDto,
  ChangeStatusDto,
  ChecklistItemBodyDto,
  AddCommentDto,
  CreateIssueDto,
  IssueSearchQueryDto,
  LinkIssueDto,
  LinkTypeParamDto,
  MyIssuesQueryDto,
  PageQueryDto,
  RankIssueDto,
  SetIssueParentDto,
  SetIssueReleaseDto,
  UpdateChecklistItemDto,
  UpdateIssueDto,
} from './dto/requests.dto';
import {
  ActivityDto,
  BulkResultDto,
  CommandResultDto,
  CommentPageDto,
  EpicDto,
  IssueDto,
  IssuePageDto,
} from './dto/responses.dto';
import { viewerOf } from '../common/viewer';
import { toBulkChange } from '../common/bulk';
import { Refs } from './refs';

const PROJECT = ApiParam({
  name: 'project',
  description: 'Project id or key',
  example: 'WEB',
});
const ISSUE = ApiParam({
  name: 'issue',
  description: 'Ticket id or key',
  example: 'WEB-12',
});

/** REST adapter of the ticket use cases: bugs, features, UI changes, tasks and QA. */
@ApiTags('Issues')
@ApiPireonAuth()
@Controller()
export class IssuesController {
  constructor(
    private readonly issues: IssuesService,
    private readonly comments: CommentsService,
    private readonly refs: Refs,
  ) {}

  @Put('issues/:issue/watch')
  @ISSUE
  @ApiOperation({
    summary: 'Follow a ticket (members, viewers included)',
    description:
      'Followers are told when it moves, is reassigned or gets a comment. Commenting follows it too.',
  })
  @ApiOkResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async watch(@CurrentUser() me: User, @Param('issue') issue: string) {
    return this.issues.watch(
      me.id,
      await this.refs.issueId(me.id, issue),
      true,
    );
  }

  @Delete('issues/:issue/watch')
  @ISSUE
  @ApiOperation({ summary: 'Stop following a ticket' })
  @ApiOkResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async unwatch(@CurrentUser() me: User, @Param('issue') issue: string) {
    return this.issues.watch(
      me.id,
      await this.refs.issueId(me.id, issue),
      false,
    );
  }

  @Get('me/issues')
  @ApiOperation({
    summary: 'My work: tickets across all my projects',
    description:
      'Assigned to me by default; with assignedToMe=false, any ticket of my projects (e.g. waiting for QA).',
  })
  @ApiOkResponse({ type: IssuePageDto })
  @ApiReadErrors()
  async mine(@CurrentUser() me: User, @Query() query: MyIssuesQueryDto) {
    const page = await this.issues.mine(me.id, {
      assignedToMe: query.assignedToMe,
      watching: query.watching,
      statuses: query.status,
      categories: query.category,
      search: query.search,
      limit: query.limit,
      offset: query.offset,
    });
    return {
      ...page,
      items: await this.refs.issueDtos(page.items, viewerOf(me)),
    };
  }

  @Get('projects/:project/issues')
  @ApiOptionalPireonAuth()
  @PROJECT
  @ApiOperation({ summary: 'Search the tickets of a project' })
  @ApiOkResponse({ type: IssuePageDto })
  @ApiReadErrors()
  async search(
    @CurrentUser() me: User | undefined,
    @Param('project') project: string,
    @Query() query: IssueSearchQueryDto,
  ) {
    const page = await this.issues.search(viewerOf(me), {
      projectId: await this.refs.projectId(viewerOf(me), project),
      parentId: query.parent
        ? await this.refs.issueId(viewerOf(me), query.parent)
        : undefined,
      statuses: query.status,
      categories: query.category,
      types: query.type,
      areas: query.area,
      priorities: query.priority,
      assigneeId: query.assigneeId,
      unassigned: query.unassigned,
      releaseId: query.releaseId,
      labels: query.label,
      sprintId: query.sprintId,
      noSprint: query.noSprint,
      watching: query.watching,
      dueFrom: query.dueFrom,
      dueTo: query.dueTo,
      customFields: query.field?.length
        ? Object.fromEntries(
            query.field.map((f) => [
              f.slice(0, f.indexOf(':')),
              f.slice(f.indexOf(':') + 1),
            ]),
          )
        : undefined,
      sort: query.sort,
      search: query.search,
      limit: query.limit,
      offset: query.offset,
    });
    return {
      ...page,
      items: await this.refs.issueDtos(page.items, viewerOf(me)),
    };
  }

  @Post('projects/:project/issues')
  @PROJECT
  @ApiOperation({
    summary: 'Create a ticket',
    description:
      "Starts in the project's first active TODO-category status (BACKLOG by default). The response carries its key (e.g. WEB-13).",
  })
  @ApiCreatedResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async create(
    @CurrentUser() me: User,
    @Param('project') project: string,
    @Body() body: CreateIssueDto,
  ) {
    const { parent, ...fields } = body;
    return this.issues.create(me.id, {
      ...withoutNulls(fields),
      projectId: await this.refs.projectId(me.id, project),
      parentId: parent ? await this.refs.issueId(me.id, parent) : null,
    });
  }

  @Get('projects/:project/epics')
  @ApiOptionalPireonAuth()
  @PROJECT
  @ApiOperation({
    summary: 'Epics: top-level tickets that group others',
    description:
      'With the progress of the tickets hanging from each one (done or cancelled, and story points).',
  })
  @ApiOkResponse({ type: [EpicDto] })
  @ApiReadErrors()
  async epics(
    @CurrentUser() me: User | undefined,
    @Param('project') project: string,
  ) {
    const epics = await this.issues.epics(
      viewerOf(me),
      await this.refs.projectId(viewerOf(me), project),
    );
    return Promise.all(
      epics.map(async (epic) => ({
        ...epic,
        issue: await this.refs.issueDto(epic.issue, viewerOf(me)),
      })),
    );
  }

  @Get('issues/:issue')
  @ApiOptionalPireonAuth()
  @ISSUE
  @ApiOperation({ summary: 'A ticket' })
  @ApiOkResponse({ type: IssueDto })
  @ApiReadErrors()
  async findOne(
    @CurrentUser() me: User | undefined,
    @Param('issue') issue: string,
  ) {
    return this.refs.issueDto(
      await this.issues.findOne(viewerOf(me), issue),
      viewerOf(me),
    );
  }

  @Patch('issues/:issue')
  @ISSUE
  @ApiOperation({
    summary: 'Edit title, description, type, priority, area, labels…',
  })
  @ApiOkResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async update(
    @CurrentUser() me: User,
    @Param('issue') issue: string,
    @Body() body: UpdateIssueDto,
  ) {
    return this.issues.update(
      me.id,
      await this.refs.issueId(me.id, issue),
      withoutNulls(body),
    );
  }

  @Put('issues/:issue/status')
  @ISSUE
  @ApiOperation({
    summary: 'Move the ticket through the workflow (incl. QA)',
    description:
      'Only the transitions in `allowedTransitions` are accepted (422 otherwise). ' +
      'QA_FAILED and CANCELLED need a reason.',
  })
  @ApiOkResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async changeStatus(
    @CurrentUser() me: User,
    @Param('issue') issue: string,
    @Body() body: ChangeStatusDto,
  ) {
    return this.issues.changeStatus(
      me.id,
      await this.refs.issueId(me.id, issue),
      body.status,
      body.reason,
    );
  }

  @Put('issues/:issue/assignee')
  @ISSUE
  @ApiOperation({ summary: 'Assign to a project member (null to unassign)' })
  @ApiOkResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async assign(
    @CurrentUser() me: User,
    @Param('issue') issue: string,
    @Body() body: AssignIssueDto,
  ) {
    return this.issues.assign(
      me.id,
      await this.refs.issueId(me.id, issue),
      body.assigneeId,
    );
  }

  @Put('issues/:issue/release')
  @ISSUE
  @ApiOperation({
    summary: 'Put the ticket in a planned release (null takes it out)',
  })
  @ApiOkResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async setRelease(
    @CurrentUser() me: User,
    @Param('issue') issue: string,
    @Body() body: SetIssueReleaseDto,
  ) {
    return this.issues.setRelease(
      me.id,
      await this.refs.issueId(me.id, issue),
      body.releaseId,
    );
  }

  @Delete('issues/:issue')
  @ISSUE
  @ApiOperation({
    summary: 'Move the ticket to the trash',
    description:
      'Whoever opened it, or an owner/admin. Hidden everywhere; restore it within 30 days or it is deleted for good.',
  })
  @ApiOkResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async trash(@CurrentUser() me: User, @Param('issue') issue: string) {
    return this.issues.trash(me.id, await this.refs.issueId(me.id, issue));
  }

  @Post('issues/:issue/restore')
  @HttpCode(200)
  @ISSUE
  @ApiOperation({ summary: 'Bring the ticket back from the trash' })
  @ApiOkResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async restore(@CurrentUser() me: User, @Param('issue') issue: string) {
    return this.issues.restore(me.id, await this.refs.issueId(me.id, issue));
  }

  @Put('issues/:issue/vote')
  @ISSUE
  @ApiOperation({
    summary: 'Vote for the ticket',
    description:
      'Anyone signed in, on a public project (that is the point: the people it is for say what they want); members on a private one. Voting twice changes nothing.',
  })
  @ApiOkResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async vote(@CurrentUser() me: User, @Param('issue') issue: string) {
    return this.issues.vote(me.id, await this.refs.issueId(me.id, issue), true);
  }

  @Delete('issues/:issue/vote')
  @ISSUE
  @ApiOperation({ summary: 'Take back my vote for the ticket' })
  @ApiOkResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async unvote(@CurrentUser() me: User, @Param('issue') issue: string) {
    return this.issues.vote(
      me.id,
      await this.refs.issueId(me.id, issue),
      false,
    );
  }

  @Post('issues/:issue/duplicate')
  @ISSUE
  @ApiOperation({
    summary: 'Duplicate the ticket',
    description:
      'Copies what it says (type, title, description, area, priority, labels, Figma, estimate, dates, parent and checklist steps, unticked), not where it stands: the copy starts in the first status, unassigned, out of sprints and releases, without comments or files. The result carries its key.',
  })
  @ApiCreatedResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async duplicate(@CurrentUser() me: User, @Param('issue') issue: string) {
    return this.issues.duplicate(me.id, await this.refs.issueId(me.id, issue));
  }

  @Get('projects/:project/trash')
  @ApiOptionalPireonAuth()
  @PROJECT
  @ApiOperation({ summary: "The project's tickets in the trash, newest first" })
  @ApiOkResponse({ type: [IssueDto] })
  @ApiReadErrors()
  async trashed(
    @CurrentUser() me: User | undefined,
    @Param('project') project: string,
  ) {
    return this.refs.issueDtos(
      await this.issues.trashed(
        viewerOf(me),
        await this.refs.projectId(viewerOf(me), project),
      ),
      viewerOf(me),
    );
  }

  @Post('issues/bulk')
  @HttpCode(200)
  @ApiOperation({
    summary: 'The same change on up to 100 tickets',
    description:
      'Each ticket goes through the normal rules (permissions, workflow, open sprints and releases) and may refuse on its own; the answer says which.',
  })
  @ApiOkResponse({ type: BulkResultDto })
  @ApiCommandErrors()
  bulkUpdate(@CurrentUser() me: User, @Body() body: BulkUpdateIssuesDto) {
    return this.issues.bulkUpdate(me.id, body.issueIds, toBulkChange(body));
  }

  @Put('issues/:issue/parent')
  @ISSUE
  @ApiOperation({
    summary: 'Place the ticket under an epic or another ticket',
    description:
      'Same project, three levels at most (epic → ticket → subtask), no loops. null takes it back to the top.',
  })
  @ApiOkResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async setParent(
    @CurrentUser() me: User,
    @Param('issue') issue: string,
    @Body() body: SetIssueParentDto,
  ) {
    return this.issues.setParent(
      me.id,
      await this.refs.issueId(me.id, issue),
      body.parent ? await this.refs.issueId(me.id, body.parent) : null,
    );
  }

  @Put('issues/:issue/rank')
  @ISSUE
  @ApiOperation({
    summary: 'Move the ticket in the backlog',
    description:
      'Between the ticket that ends up above it and the one below (either may be left out for the top or the bottom). Board columns follow the same order.',
  })
  @ApiOkResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async rank(
    @CurrentUser() me: User,
    @Param('issue') issue: string,
    @Body() body: RankIssueDto,
  ) {
    const ref = (value?: string | null) =>
      value ? this.refs.issueId(me.id, value) : null;
    return this.issues.rank(
      me.id,
      await this.refs.issueId(me.id, issue),
      await ref(body.above),
      await ref(body.below),
    );
  }

  @Post('issues/:issue/checklist')
  @ISSUE
  @ApiOperation({ summary: "Add a step to the ticket's checklist" })
  @ApiCreatedResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async addChecklistItem(
    @CurrentUser() me: User,
    @Param('issue') issue: string,
    @Body() body: ChecklistItemBodyDto,
  ) {
    return this.issues.addChecklistItem(
      me.id,
      await this.refs.issueId(me.id, issue),
      body.text,
    );
  }

  @Patch('issues/:issue/checklist/:item')
  @ISSUE
  @ApiParam({ name: 'item', format: 'uuid' })
  @ApiOperation({ summary: 'Reword, tick or untick a checklist step' })
  @ApiOkResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async updateChecklistItem(
    @CurrentUser() me: User,
    @Param('issue') issue: string,
    @Param('item', ParseUUIDPipe) item: string,
    @Body() body: UpdateChecklistItemDto,
  ) {
    return this.issues.updateChecklistItem(
      me.id,
      await this.refs.issueId(me.id, issue),
      item,
      body,
    );
  }

  @Delete('issues/:issue/checklist/:item')
  @ISSUE
  @ApiParam({ name: 'item', format: 'uuid' })
  @ApiOperation({ summary: 'Remove a checklist step' })
  @ApiOkResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async removeChecklistItem(
    @CurrentUser() me: User,
    @Param('issue') issue: string,
    @Param('item', ParseUUIDPipe) item: string,
  ) {
    return this.issues.removeChecklistItem(
      me.id,
      await this.refs.issueId(me.id, issue),
      item,
    );
  }

  @Post('issues/:issue/links')
  @ISSUE
  @ApiOperation({
    summary: 'Relate tickets (FE ↔ BE ↔ QA)',
    description:
      'e.g. WEB-3 DEPENDS_ON API-7, WEB-9 TESTS WEB-3. May cross projects.',
  })
  @ApiCreatedResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async link(
    @CurrentUser() me: User,
    @Param('issue') issue: string,
    @Body() body: LinkIssueDto,
  ) {
    return this.issues.link(me.id, {
      issueId: await this.refs.issueId(me.id, issue),
      type: body.type,
      targetIssueId: await this.refs.issueId(me.id, body.targetIssue),
    });
  }

  @Delete('issues/:issue/links/:type/:target')
  @ISSUE
  @ApiParam({ name: 'type', enum: IssueLinkType, enumName: 'IssueLinkType' })
  @ApiParam({ name: 'target', description: 'Other ticket: id or key' })
  @ApiOperation({ summary: 'Remove a relation' })
  @ApiOkResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async unlink(
    @CurrentUser() me: User,
    @Param('issue') issue: string,
    @Param() params: LinkTypeParamDto,
    @Param('target') target: string,
  ) {
    return this.issues.unlink(me.id, {
      issueId: await this.refs.issueId(me.id, issue),
      type: params.type,
      targetIssueId: await this.refs.issueId(me.id, target),
    });
  }

  @Get('issues/:issue/comments')
  @ApiOptionalPireonAuth()
  @ISSUE
  @ApiOperation({ summary: 'Comments of the ticket (oldest first)' })
  @ApiOkResponse({ type: CommentPageDto })
  @ApiReadErrors()
  async listComments(
    @CurrentUser() me: User | undefined,
    @Param('issue') issue: string,
    @Query() page: PageQueryDto,
  ) {
    return this.comments.list(
      viewerOf(me),
      await this.refs.issueId(viewerOf(me), issue),
      page.limit,
      page.offset,
    );
  }

  @Post('issues/:issue/comments')
  @ISSUE
  @ApiOperation({
    summary: 'Comment on the ticket, or answer a comment (replyTo)',
  })
  @ApiCreatedResponse({ type: CommandResultDto })
  @ApiCommandErrors()
  async addComment(
    @CurrentUser() me: User,
    @Param('issue') issue: string,
    @Body() body: AddCommentDto,
  ) {
    return this.comments.add(
      me.id,
      await this.refs.issueId(me.id, issue),
      body.body,
      body.replyTo ?? null,
    );
  }

  @Get('issues/:issue/history')
  @ApiOptionalPireonAuth()
  @ISSUE
  @ApiOperation({ summary: 'History of the ticket (newest first)' })
  @ApiOkResponse({ type: [ActivityDto] })
  @ApiReadErrors()
  async history(
    @CurrentUser() me: User | undefined,
    @Param('issue') issue: string,
    @Query() page: PageQueryDto,
  ) {
    const found = await this.issues.findOne(viewerOf(me), issue);
    return this.issues.activity(viewerOf(me), {
      projectId: found.projectId,
      issueId: found.id,
      limit: page.limit,
    });
  }
}