import { describe, expect, it } from "bun:test";

describe("Reconnection Integration", () => {
    describe("Backoff calculations", () => {
        it("should use correct standard exponential backoff", () => {
            const calculateStandardBackoff = (attempt: number) => {
                return Math.min(1000 * 2 ** attempt, 30000);
            };

            expect(calculateStandardBackoff(0)).toBe(1000); // 1s
            expect(calculateStandardBackoff(1)).toBe(2000); // 2s
            expect(calculateStandardBackoff(2)).toBe(4000); // 4s
            expect(calculateStandardBackoff(3)).toBe(8000); // 8s
            expect(calculateStandardBackoff(4)).toBe(16000); // 16s
            expect(calculateStandardBackoff(5)).toBe(30000); // 30s (capped)
            expect(calculateStandardBackoff(6)).toBe(30000); // 30s (remains capped)
        });

        it("should use aggressive backoff for idle/wake scenarios", () => {
            const aggressiveDelays = [0, 1000, 2000, 5000, 10000, 30000];

            const getAggressiveDelay = (attempt: number) => {
                return aggressiveDelays[Math.min(attempt, aggressiveDelays.length - 1)];
            };

            expect(getAggressiveDelay(0)).toBe(0); // Immediate
            expect(getAggressiveDelay(1)).toBe(1000); // 1s
            expect(getAggressiveDelay(2)).toBe(2000); // 2s
            expect(getAggressiveDelay(3)).toBe(5000); // 5s
            expect(getAggressiveDelay(4)).toBe(10000); // 10s
            expect(getAggressiveDelay(5)).toBe(30000); // 30s
            expect(getAggressiveDelay(10)).toBe(30000); // Still 30s for any higher attempt
        });

        it("should be much faster than old broken implementation", () => {
            // Old broken calculation
            const oldBrokenDelay = (attempt: number) => {
                return (1000 * (attempt + 1)) ** 2;
            };

            // New correct calculation
            const newDelay = (attempt: number) => {
                return Math.min(1000 * 2 ** attempt, 30000);
            };

            // Compare first attempt
            const oldFirst = oldBrokenDelay(0); // 1,000,000ms (16.7 minutes)
            const newFirst = newDelay(0); // 1,000ms (1 second)
            expect(oldFirst / newFirst).toBe(1000); // 1000x improvement

            // Compare second attempt
            const oldSecond = oldBrokenDelay(1); // 4,000,000ms (66.7 minutes)
            const newSecond = newDelay(1); // 2,000ms (2 seconds)
            expect(oldSecond / newSecond).toBe(2000); // 2000x improvement
        });
    });

    describe("Sleep detection logic", () => {
        it("should detect sleep through time gaps", () => {
            const checkForSleep = (lastCheck: number, now: number, threshold = 15000) => {
                const elapsed = now - lastCheck;
                return elapsed > threshold;
            };

            // Normal 10s check - no sleep
            const normalCheck = checkForSleep(Date.now() - 10000, Date.now());
            expect(normalCheck).toBe(false);

            // 20s gap - likely sleep
            const sleepCheck = checkForSleep(Date.now() - 20000, Date.now());
            expect(sleepCheck).toBe(true);
        });

        it("should mark connection as idle after 2 minutes", () => {
            const checkIfIdle = (lastMessageSent: number, idleThreshold = 120000) => {
                return Date.now() - lastMessageSent > idleThreshold;
            };

            // Recent activity - not idle
            const recentActivity = checkIfIdle(Date.now() - 60000); // 1 minute ago
            expect(recentActivity).toBe(false);

            // Old activity - idle
            const oldActivity = checkIfIdle(Date.now() - 150000); // 2.5 minutes ago
            expect(oldActivity).toBe(true);
        });
    });

    describe("System-wide detection", () => {
        it("should detect system-wide disconnection", () => {
            const checkSystemWide = (disconnections: number[], totalRelays: number, threshold = 0.5) => {
                const now = Date.now();
                const recentDisconnections = disconnections.filter((time) => now - time < 5000);
                return totalRelays > 1 && recentDisconnections.length > totalRelays * threshold;
            };

            const now = Date.now();

            // 3 out of 5 relays disconnect within 5s - system event
            const systemEvent = checkSystemWide([now - 1000, now - 2000, now - 3000], 5);
            expect(systemEvent).toBe(true);

            // 2 out of 5 relays - not system event
            const normalEvent = checkSystemWide([now - 1000, now - 2000], 5);
            expect(normalEvent).toBe(false);

            // Single relay pool - never system event
            const singleRelay = checkSystemWide([now], 1);
            expect(singleRelay).toBe(false);
        });
    });
});