import type { LucideIcon } from 'lucide-react';
import {
  AlertCircle,
  CalendarDays,
  ClipboardList,
  FlaskConical,
  Link2,
  Stethoscope,
  UserCog,
  Users,
} from 'lucide-react';
import type { Organization } from '@/types/organization';
import {
  canEditStaff,
  canViewAppointmentsTab,
  canViewCases,
  canViewStaff,
  canViewTasks,
  canViewTreatment,
  hasPermission,
  type OrgTypeName,
} from '@/components/shared/permissions';
import type { TodaySummaryWidgets, TodayWidgetKey } from '@/types/today';

export type KpiCardColor = 'blue' | 'yellow' | 'green' | 'red' | 'purple' | 'default';

export interface TodayKpiDefinition {
  key: TodayWidgetKey;
  titleKey: string;
  icon: LucideIcon;
  color: KpiCardColor;
  orgTypes: OrgTypeName[];
  href: string;
  isVisible: (org: Organization | null) => boolean;
  formatValue: (widgets: TodaySummaryWidgets) => string | null;
  formatSubtitle?: (widgets: TodaySummaryWidgets) => string | null;
}

function countWidget(
  widgets: TodaySummaryWidgets,
  key: TodayWidgetKey,
): number | null {
  const value = widgets[key];
  if (!value || !('count' in value)) return null;
  return value.count;
}

function canManageOrganizations(org: Organization | null): boolean {
  if (!org) return false;
  if (org.isOwner) return true;
  return hasPermission(org, 'TAB_ORGANIZATIONS_EDIT');
}

function canViewPatients(org: Organization | null): boolean {
  if (!org) return false;
  return (
    hasPermission(org, 'TAB_PATIENTS_READ') ||
    hasPermission(org, 'TAB_PATIENTS_EDIT')
  );
}

export const TODAY_KPI_DEFINITIONS: TodayKpiDefinition[] = [
  {
    key: 'appointmentsToday',
    titleKey: 'widgetAppointmentsToday',
    icon: CalendarDays,
    color: 'blue',
    orgTypes: ['CLINIC'],
    href: '/appointments',
    isVisible: (org) => canViewAppointmentsTab(org),
    formatValue: (widgets) => {
      const count = countWidget(widgets, 'appointmentsToday');
      return count === null ? null : String(count);
    },
  },
  {
    key: 'patientsToday',
    titleKey: 'widgetPatientsToday',
    icon: Users,
    color: 'green',
    orgTypes: ['CLINIC'],
    href: '/patients',
    isVisible: (org) => canViewPatients(org) || canViewAppointmentsTab(org),
    formatValue: (widgets) => {
      const count = countWidget(widgets, 'patientsToday');
      return count === null ? null : String(count);
    },
  },
  {
    key: 'treatmentsToday',
    titleKey: 'widgetTreatmentsToday',
    icon: Stethoscope,
    color: 'purple',
    orgTypes: ['CLINIC'],
    href: '/treatment',
    isVisible: (org) => canViewTreatment(org),
    formatValue: (widgets) => {
      const count = countWidget(widgets, 'treatmentsToday');
      return count === null ? null : String(count);
    },
  },
  {
    key: 'labCasesPendingSend',
    titleKey: 'widgetLabCasesPendingSend',
    icon: FlaskConical,
    color: 'red',
    orgTypes: ['CLINIC'],
    href: '/treatment',
    isVisible: (org) => canViewTreatment(org),
    formatValue: (widgets) => {
      const count = countWidget(widgets, 'labCasesPendingSend');
      return count === null ? null : String(count);
    },
  },
  {
    key: 'providersWithoutWorkingHours',
    titleKey: 'widgetProvidersWithoutWorkingHours',
    icon: UserCog,
    color: 'yellow',
    orgTypes: ['CLINIC'],
    href: '/staff',
    isVisible: (org) => canViewStaff(org),
    formatValue: (widgets) => {
      const count = countWidget(widgets, 'providersWithoutWorkingHours');
      return count === null ? null : String(count);
    },
  },
  {
    key: 'casesReceivedToday',
    titleKey: 'widgetCasesReceivedToday',
    icon: FlaskConical,
    color: 'blue',
    orgTypes: ['LAB'],
    href: '/cases',
    isVisible: (org) => canViewCases(org),
    formatValue: (widgets) => {
      const count = countWidget(widgets, 'casesReceivedToday');
      return count === null ? null : String(count);
    },
  },
  {
    key: 'casesInProgress',
    titleKey: 'widgetCasesInProgress',
    icon: FlaskConical,
    color: 'yellow',
    orgTypes: ['LAB'],
    href: '/cases',
    isVisible: (org) => canViewCases(org),
    formatValue: (widgets) => {
      const count = countWidget(widgets, 'casesInProgress');
      return count === null ? null : String(count);
    },
  },
  {
    key: 'tasksInProgress',
    titleKey: 'widgetTasksInProgress',
    icon: ClipboardList,
    color: 'yellow',
    orgTypes: ['LAB'],
    href: '/tasks',
    isVisible: (org) => canViewTasks(org),
    formatValue: (widgets) => {
      const count = countWidget(widgets, 'tasksInProgress');
      return count === null ? null : String(count);
    },
  },
  {
    key: 'importantTasks',
    titleKey: 'widgetImportantTasks',
    icon: AlertCircle,
    color: 'red',
    orgTypes: ['LAB'],
    href: '/tasks',
    isVisible: (org) => canViewTasks(org),
    formatValue: (widgets) => {
      const count = countWidget(widgets, 'importantTasks');
      return count === null ? null : String(count);
    },
  },
  {
    key: 'pendingConnections',
    titleKey: 'widgetPendingConnections',
    icon: Link2,
    color: 'yellow',
    orgTypes: ['CLINIC', 'LAB'],
    href: '/organizations',
    isVisible: (org) => canManageOrganizations(org),
    formatValue: (widgets) => {
      const count = countWidget(widgets, 'pendingConnections');
      return count === null ? null : String(count);
    },
  },
  {
    key: 'pendingStaffInvites',
    titleKey: 'widgetPendingStaffInvites',
    icon: UserCog,
    color: 'purple',
    orgTypes: ['CLINIC', 'LAB'],
    href: '/staff',
    isVisible: (org) => canEditStaff(org) || Boolean(org?.isOwner),
    formatValue: (widgets) => {
      const count = countWidget(widgets, 'pendingStaffInvites');
      return count === null ? null : String(count);
    },
  },
];

export function getEligibleTodayKpis(org: Organization | null): TodayKpiDefinition[] {
  if (!org) return [];

  return TODAY_KPI_DEFINITIONS.filter((definition) => {
    if (!definition.orgTypes.includes(org.type)) return false;
    return definition.isVisible(org);
  });
}

export function getVisibleTodayKpis(
  org: Organization | null,
  widgets: TodaySummaryWidgets,
): TodayKpiDefinition[] {
  return getEligibleTodayKpis(org).filter(
    (definition) => definition.formatValue(widgets) !== null,
  );
}