import type { StatusCount } from "@/components/ui/ItProgress.vue";
import { percentToRoundedGrade } from "@/services/assignmentService";
import type { CompetenceCertificate, CompetenceCertificateAssignment } from "@/types";
import dayjs from "dayjs";
import _ from "lodash";

export function assignmentsMaxEvaluationPoints(
  assignments: CompetenceCertificateAssignment[]
): number {
  return _.sum(
    assignments
      .filter((a) => a.completions[0]?.completion_status === "EVALUATION_SUBMITTED")
      .map((a) => a.max_points)
  );
}

export function assignmentsUserPoints(assignments: CompetenceCertificateAssignment[]) {
  return +_.sum(
    assignments
      .filter((a) => a.completions?.[0]?.completion_status === "EVALUATION_SUBMITTED")
      .map((a) => a.completions?.[0]?.evaluation_points_final ?? 0)
  ).toFixed(1);
}

export function calcCompetenceCertificateGrade(
  assignments: CompetenceCertificateAssignment[],
  roundedToHalfGrade = true
) {
  const evaluatedAssignments = assignments.filter(
    (a) => a.completions?.[0]?.completion_status === "EVALUATION_SUBMITTED"
  );

  const adjustedResults = evaluatedAssignments.map((a) => {
    return (
      ((a.completions?.[0]?.evaluation_points_final ?? 0) / a.max_points) *
      a.competence_certificate_weight
    );
  });

  const adjustedAssignmentCount = _.sum(
    evaluatedAssignments.map((a) => a.competence_certificate_weight)
  );

  if (adjustedAssignmentCount === 0) {
    return undefined;
  }

  return percentToRoundedGrade(
    _.sum(adjustedResults) / adjustedAssignmentCount,
    roundedToHalfGrade
  );
}

export function calcCompetencesTotalGrade(
  competenceCertificates: CompetenceCertificate[]
) {
  // für das Total der Kompetenznote werden jeweils die gerundenten Noten der
  // einzelnen Kompetenznachweise verwendet und dann noch einmal gerundet.
  const competenceCertificateGrades = competenceCertificates
    .map((cc) => {
      return calcCompetenceCertificateGrade(cc.assignments);
    })
    .filter((g) => {
      // filter out "empty" grades
      return !!g;
    });

  const percentGraded =
    // @ts-ignore `g` cannot be undefined here
    _.sum(competenceCertificateGrades.map((g) => g - 1)) /
    (competenceCertificateGrades.length * 5);

  return percentToRoundedGrade(percentGraded);
}

export function competenceCertificateProgressStatusCount(
  assignments: CompetenceCertificateAssignment[]
) {
  const numAssignmentsEvaluated = assignments.filter(
    (a) => a.completions?.[0]?.completion_status === "EVALUATION_SUBMITTED"
  ).length;
  return {
    SUCCESS: numAssignmentsEvaluated,
    UNKNOWN: assignments.length - numAssignmentsEvaluated,
    FAIL: 0,
  } as StatusCount;
}

export function mergeCompetenceCertificates(
  competenceCertificates: CompetenceCertificate[]
) {
  const groupedCompetenceCertificates: Record<
    string,
    Array<CompetenceCertificate>
  > = {};
  competenceCertificates.forEach((certificate) => {
    if (!certificate) {
      return;
    }
    if (!groupedCompetenceCertificates[certificate.id]) {
      groupedCompetenceCertificates[certificate.id] = [];
    }
    groupedCompetenceCertificates[certificate.id].push(certificate);
  });

  console.log(
    `Found ${Object.keys(groupedCompetenceCertificates).length} competence certificates over all course sessions`
  );

  return Object.values(groupedCompetenceCertificates).map((certificates) => {
    const mergedCertificate: CompetenceCertificate = {
      ...certificates[0],
      assignments: [],
    };
    certificates.forEach((certificate) => {
      certificate.assignments.forEach((assignment) => {
        const existingAssignment = mergedCertificate.assignments.find(
          (a) => a.id === assignment.id
        );
        if (!existingAssignment) {
          mergedCertificate.assignments.push(assignment);
        } else if (
          assignment.completions?.[0] != null &&
          (existingAssignment.completions?.[0] == null ||
            dayjs(existingAssignment.completions[0].evaluation_submitted_at).isBefore(
              assignment.completions[0].evaluation_submitted_at
            ))
        ) {
          mergedCertificate.assignments.splice(
            mergedCertificate.assignments.findIndex((a) => a.id === assignment.id),
            1
          );
          mergedCertificate.assignments.push(assignment);
        }
      });
    });
    return mergedCertificate;
  });
}