Motivational Slack Bot

route.ts

import { log } from "@interfere/observability/log";
import { WebClient } from "@slack/web-api";
import { generateText } from "ai";
import dayjs from "dayjs";
import timezone from "dayjs/plugin/timezone";
import utc from "dayjs/plugin/utc";
import { Context, Effect, Layer, Schema } from "effect";
import { NextResponse } from "next/server";
import { env } from "@/env";

// Configure dayjs with timezone support
dayjs.extend(utc);
dayjs.extend(timezone);

export const runtime = "nodejs";

const PostResult = Schema.Struct({
  ok: Schema.Boolean,
  days: Schema.Number,
  text: Schema.String,
});

type PostResult = Schema.Schema.Type<typeof PostResult>;

class SlackClient extends Context.Tag("services/SlackClient")<
  SlackClient,
  WebClient
>() {}

const SlackLayer = Layer.succeed(
  SlackClient,
  new WebClient(env.SLACK_BOT_TOKEN)
);

/**
 * Calculate days between start date and now in a specific timezone
 * Uses day.js for reliable timezone handling
 */
const computeDay = (now: Date, startISO: string, tz: string): number => {
  // Parse the start date as a date in the target timezone
  const startDate = dayjs.tz(startISO, tz).startOf("day");

  // Get the current date in the target timezone
  const currentDate = dayjs(now).tz(tz).startOf("day");

  // Calculate the difference in days
  const diffDays = currentDate.diff(startDate, "day");

  // Add 1 because we count the first day as Day 1
  return Math.max(1, diffDays + 1);
};

// Examples for inspiration (not preferred; model may create or adapt)
const INSPIRATION_QUOTES = [
  '"Discipline equals freedom." - Jocko Willink',
  '"The obstacle is the way." - Marcus Aurelius',
  '"Less is more." - Ludwig Mies van der Rohe',
  '"Form follows function." - Louis Sullivan',
  '"Less, but better." - Dieter Rams',
  '"The details are not the details. They make the design." - Charles Eames',
  '"Above all else show the data." - Edward Tufte',
  '"Simplicity is the ultimate sophistication." - Leonardo da Vinci',
  '"Ship early, ship often." - Eric S. Raymond',
  '"Done is better than perfect." - Sheryl Sandberg',
  '"The best time to plant a tree was 20 years ago. The second best time is now." - Chinese Proverb',
  '"Build something 100 people love, not something 1 million people kind of like." - Brian Chesky',
  '"Ideas are worthless. Execution is everything." - Scott Adams',
  '"If you\'re not embarrassed by v1, you launched too late." - Reid Hoffman',
  '"The biggest risk is not taking any risk." - Mark Zuckerberg',
  '"Your work is going to fill a large part of your life, do what you believe is great work." - Steve Jobs',
] as const;

const RANDOM_SORT_MIDPOINT = 0.5;
const EXAMPLE_QUOTES_SAMPLE_SIZE = 5;

const generateAIQuote = async (dayNumber: number): Promise<string | null> => {
  // Randomly select example quotes for variety
  const shuffled = [...INSPIRATION_QUOTES].sort(
    () => Math.random() - RANDOM_SORT_MIDPOINT
  );
  const selectedExamples = shuffled.slice(0, EXAMPLE_QUOTES_SAMPLE_SIZE);
  const list = selectedExamples.join("\n");

  // Use day number as a seed for variety
  const themes = [
    "building",
    "shipping",
    "design",
    "engineering",
    "teamwork",
    "innovation",
    "quality",
    "craftsmanship",
    "persistence",
    "focus",
    "iteration",
    "simplicity",
    "excellence",
    "growth",
    "momentum",
  ];
  const theme = themes[dayNumber % themes.length];

  // Additional variety factors
  const styleOptions = [
    "bold and direct",
    "philosophical and thoughtful",
    "practical and actionable",
    "minimalist and zen-like",
    "energetic and motivating",
  ];

  const style = styleOptions[Math.floor(Math.random() * styleOptions.length)];

  const prompt = [
    `Generate a unique, inspiring quote for Day ${dayNumber} of a startup journey.`,
    `Theme focus: ${theme}`,
    `Style: ${style}`,
    "Requirements:",
    '- Create something fresh and varied - avoid repetitive phrases about "progress" or "steps"',
    "- Can be about engineering, design, startups, excellence, or general wisdom",
    "- Keep it concise (under 100 chars)",
    "- IMPORTANT: Attribute to a real person (tech leaders, designers, philosophers, etc.). Do not create an original saying.",
    `- Match the "${style}" tone`,
    "Examples for style reference (note the mix of attributed and non-attributed):",
    list,
    '"Make it happen." (no attribution)',
    '"Quality is non-negotiable." (no attribution)',
    "",
    'Return ONLY the quote text. Include " - Name" ONLY if citing a real person.',
  ].join("\n");

  const result = await generateText({
    model: "openai/gpt-5-mini",
    prompt,
    temperature: 1,
  });

  const out = typeof result.text === "string" ? result.text.trim() : "";
  if (!out) {
    return null;
  }
  return out;
};

const program = Effect.gen(function* () {
  const tz = "America/New_York";

  const days = computeDay(new Date(), "2025-06-30", tz);

  // Try AI-generated quote; if none, omit quote entirely
  const maybeQuote = yield* Effect.tryPromise({
    try: () => generateAIQuote(days),
    catch: (e) => log.error("Failed to generate AI quote", e),
  });

  const text = maybeQuote
    ? `Today is *Day ${days}* of Interfere. Make it count.\n\n> ${maybeQuote}`
    : `Today is *Day ${days}* of Interfere. Make it count.`;

  const slack = yield* SlackClient;

  const res = yield* Effect.tryPromise({
    try: () =>
      slack.chat.postMessage({
        channel: env.SLACK_CHANNEL_ID,
        text,
        mrkdwn: true,
      }),
    catch: (e: unknown) => e,
  });

  if (!res.ok) {
    return yield* Effect.fail(
      new Error(typeof res.error === "string" ? res.error : "Slack API error")
    );
  }

  const payload: PostResult = { ok: true, days, text };

  return payload;
});

export async function GET(_request: Request) {
  const authHeader = _request.headers.get("authorization");

  if (authHeader !== `Bearer ${env.CRON_SECRET}`) {
    return NextResponse.json(
      { ok: false, error: "Unauthorized" },
      { status: 401 }
    );
  }

  const result = await Effect.runPromise(
    Effect.provide(program, SlackLayer)
  ).then(
    (ok) => ({ status: 200, body: ok }),
    (err) => ({
      status: 500,
      body: {
        ok: false,
        error:
          (err && (err.data || err.message)) ??
          "Failed to post message to Slack",
      },
    })
  );

  return NextResponse.json(result.body, { status: result.status });
}

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