import { z } from "zod";

export const severitySchema = z.enum(["critical", "serious", "moderate", "minor"]);
export type Severity = z.infer<typeof severitySchema>;

export const severityLevelSchema = z.enum(["error", "warn"]);
export type SeverityLevel = z.infer<typeof severityLevelSchema>;

export const legacySeverityLevelSchema = z.enum(["error", "warn", "info", "warning"]);
export type LegacySeverityLevel = z.infer<typeof legacySeverityLevelSchema>;

export const SEVERITIES = severitySchema.options;

export const SEVERITY_WEIGHTS: Record<Severity, number> = {
  critical: 10,
  serious: 5,
  moderate: 2,
  minor: 1,
};

export const SEVERITY_RANK: Record<Severity, number> = {
  critical: 4,
  serious: 3,
  moderate: 2,
  minor: 1,
};

export function severityLevel(severity: Severity): SeverityLevel {
  return severity === "critical" || severity === "serious" ? "error" : "warn";
}

export function severityFromLevel(level: LegacySeverityLevel): Severity {
  switch (level) {
    case "error":
      return "serious";
    case "warn":
    case "warning":
      return "moderate";
    case "info":
      return "minor";
  }
}

export function compareSeverity(a: Severity, b: Severity): number {
  return SEVERITY_RANK[b] - SEVERITY_RANK[a];
}

export function maxSeverity(a: Severity, b: Severity): Severity {
  return SEVERITY_RANK[a] >= SEVERITY_RANK[b] ? a : b;
}

export function sortBySeverity<T>(items: readonly T[], getSeverity: (item: T) => Severity): T[] {
  return items.slice().sort((a, b) => compareSeverity(getSeverity(a), getSeverity(b)));
}