import type { BigCalendarEvent, CalendarProjectionItem } from "../api/types";
import type { IEvent, IUser } from "../upstream-big-calendar/interfaces";

interface LegacyBigCalendarAction {
  type: "move" | "resize";
  event: BigCalendarEvent;
  start: string;
  end: string;
}

interface LegacyBigCalendarActivityCommand {
  type: "reschedule";
  activityId: string;
  scheduledStartAt: string;
  scheduledEndAt: string;
}

export interface UpstreamCalendarActivityCommand {
  type: "reschedule";
  activityId: string;
  scheduledStartAt: string;
  scheduledEndAt: string;
}

export function mapCalendarProjectionToBigCalendarEvent(
  item: CalendarProjectionItem
): BigCalendarEvent {
  const activityEditable = item.editable && !item.milestone && item.activityId !== null;

  return {
    id: item.id,
    title: item.title,
    start: item.startAt,
    end: item.endAt,
    allDay: item.allDay,
    editable: activityEditable,
    draggable: activityEditable,
    resizable: activityEditable,
    category: item.category,
    priority: item.priority,
    source: {
      entityType: item.entityType,
      entityId: item.entityId,
      activityId: item.activityId,
      customerId: item.customerId,
      leadId: item.leadId,
      opportunityId: item.opportunityId,
      quotationId: item.quotationId,
      approvalId: item.approvalId,
      ownerId: item.ownerId,
      assigneeId: item.assigneeId
    },
    display: {
      summary: item.summary,
      location: item.location,
      overdue: item.overdue,
      hotProject: item.hotProject,
      milestone: item.milestone
    }
  };
}

export function mapBigCalendarActionToActivityCommand(
  action: LegacyBigCalendarAction
): LegacyBigCalendarActivityCommand | null {
  if (!action.event.editable || !action.event.source.activityId) return null;

  return {
    type: "reschedule",
    activityId: action.event.source.activityId,
    scheduledStartAt: action.start,
    scheduledEndAt: action.end
  };
}

export function mapCalendarProjectionToUpstreamEvent(item: CalendarProjectionItem): IEvent {
  const editable = item.editable && !item.milestone && item.activityId !== null;

  return {
    id: item.id,
    title: item.title,
    startDate: item.startAt,
    endDate: item.endAt,
    color: mapCalendarColor(item),
    description: [item.summary, item.location].filter(Boolean).join(" - "),
    user: mapCrmCalendarUserToUpstreamUser(item),
    alla: {
      activityId: item.activityId,
      editable,
      milestone: item.milestone,
      sourceEntityType: item.entityType,
      sourceEntityId: item.entityId,
      customerId: item.customerId,
      leadId: item.leadId,
      opportunityId: item.opportunityId,
      quotationId: item.quotationId,
      approvalId: item.approvalId,
      overdue: item.overdue,
      hotProject: item.hotProject,
      pricingSensitive: item.visibility.pricingSensitive,
      internalOnly: item.visibility.internalOnly
    }
  };
}

export function mapCrmCalendarUserToUpstreamUser(item: CalendarProjectionItem): IUser {
  const id = item.assigneeId ?? item.ownerId ?? "unassigned";

  return {
    id,
    name: id === "unassigned" ? "Unassigned" : `User ${id.slice(0, 8)}`,
    picturePath: null
  };
}

export function mapUpstreamEventToActivityCommand(
  event: IEvent
): UpstreamCalendarActivityCommand | null {
  if (!event.alla?.editable || !event.alla.activityId) return null;

  return {
    type: "reschedule",
    activityId: event.alla.activityId,
    scheduledStartAt: event.startDate,
    scheduledEndAt: event.endDate
  };
}

function mapCalendarColor(item: CalendarProjectionItem): IEvent["color"] {
  if (item.overdue) return "red";
  if (item.hotProject) return "orange";
  if (item.milestone) return "purple";
  if (item.priority === "critical") return "red";
  if (item.priority === "high") return "yellow";
  if (item.category === "meeting") return "blue";
  if (item.category === "visit" || item.category === "site_survey") return "green";
  return "gray";
}