"use client";

import type { EntryWithTags } from "@/lib/types";
import { isWithinWeek } from "@/lib/utils/date";

interface WeeklyReflectionProps {
  entries: EntryWithTags[];
}

export function WeeklyReflection({ entries }: WeeklyReflectionProps) {
  // Filter to last 7 days
  const weekEntries = entries.filter((e) => isWithinWeek(e.date));

  if (weekEntries.length === 0) {
    return null;
  }

  // Count tag occurrences
  const tagCounts = new Map<string, { name: string; count: number }>();
  for (const entry of weekEntries) {
    for (const tag of entry.tags) {
      const existing = tagCounts.get(tag.id);
      if (existing) {
        existing.count++;
      } else {
        tagCounts.set(tag.id, { name: tag.name, count: 1 });
      }
    }
  }

  // Get top 3 tags
  const topTags = Array.from(tagCounts.values())
    .sort((a, b) => b.count - a.count)
    .slice(0, 3);

  // Generate summary
  let summary = "";
  if (topTags.length > 0) {
    const tagNames = topTags.map((t) => capitalize(t.name));
    if (tagNames.length === 1) {
      summary = `You mentioned: ${tagNames[0]}.`;
    } else if (tagNames.length === 2) {
      summary = `You mentioned: ${tagNames[0]} and ${tagNames[1]}.`;
    } else {
      summary = `You mentioned: ${tagNames.slice(0, -1).join(", ")}, and ${tagNames[tagNames.length - 1]}.`;
    }
  }

  return (
    <div className="bg-surface border border-border rounded-xl p-4 mb-6">
      <h2 className="text-sm font-medium text-muted mb-2">This week</h2>
      <div className="flex items-baseline gap-4 mb-2">
        <span className="text-2xl font-light">{weekEntries.length}</span>
        <span className="text-sm text-muted">
          {weekEntries.length === 1 ? "entry" : "entries"}
        </span>
      </div>
      {summary && <p className="text-sm text-muted italic">{summary}</p>}
    </div>
  );
}

function capitalize(str: string): string {
  return str.charAt(0).toUpperCase() + str.slice(1);
}