import test from "node:test";
import assert from "node:assert/strict";
import fs from "node:fs";
import os from "node:os";
import path from "node:path";

const TEST_DATA_DIR = fs.mkdtempSync(path.join(os.tmpdir(), "omniroute-domain-cost-"));
process.env.DATA_DIR = TEST_DATA_DIR;

const core = await import("../../src/lib/db/core.ts");
const costRules = await import("../../src/domain/costRules.ts");
const domainState = await import("../../src/lib/db/domainState.ts");

async function resetStorage() {
  costRules.resetCostData();
  core.resetDbInstance();

  for (let attempt = 0; attempt < 10; attempt++) {
    try {
      if (fs.existsSync(TEST_DATA_DIR)) {
        fs.rmSync(TEST_DATA_DIR, { recursive: true, force: true });
      }
      break;
    } catch (error: any) {
      if ((error?.code === "EBUSY" || error?.code === "EPERM") && attempt < 9) {
        await new Promise((resolve) => setTimeout(resolve, 50 * (attempt + 1)));
      } else {
        throw error;
      }
    }
  }

  fs.mkdirSync(TEST_DATA_DIR, { recursive: true });
}

test.beforeEach(async () => {
  await resetStorage();
});

test.after(async () => {
  costRules.resetCostData();
  core.resetDbInstance();
  fs.rmSync(TEST_DATA_DIR, { recursive: true, force: true });
});

test("setBudget normalizes defaults and getBudget returns the stored config", () => {
  costRules.setBudget("key-budget", { dailyLimitUsd: 12.5 });

  assert.deepEqual(costRules.getBudget("key-budget"), {
    dailyLimitUsd: 12.5,
    weeklyLimitUsd: 0,
    monthlyLimitUsd: 0,
    warningThreshold: 0.8,
    resetInterval: "daily",
    resetTime: "00:00",
    budgetResetAt: costRules.getBudget("key-budget")?.budgetResetAt ?? null,
    lastBudgetResetAt: costRules.getBudget("key-budget")?.lastBudgetResetAt ?? null,
    warningEmittedAt: null,
    warningPeriodStart: null,
  });
  assert.equal(costRules.getBudget("missing-key"), null);
});

test("checkBudget reports warning and blocks when projected spend exceeds the daily cap", () => {
  costRules.setBudget("key-warning", {
    dailyLimitUsd: 10,
    warningThreshold: 0.6,
  });
  costRules.recordCost("key-warning", 5);

  const warning = costRules.checkBudget("key-warning", 1);
  const denied = costRules.checkBudget("key-warning", 6);

  assert.deepEqual(warning, {
    allowed: true,
    dailyUsed: 5,
    dailyLimit: 10,
    warningReached: true,
    remaining: 4,
    periodUsed: 5,
    activeLimitUsd: 10,
    resetInterval: "daily",
    resetTime: "00:00",
    budgetResetAt: warning.budgetResetAt,
    lastBudgetResetAt: warning.lastBudgetResetAt,
    periodStartAt: warning.periodStartAt,
  });
  assert.equal(denied.allowed, false);
  assert.equal(denied.warningReached, true);
  assert.match(denied.reason, /Daily budget exceeded/);
});

test("getDailyTotal and getCostSummary split daily and monthly totals correctly", () => {
  const OriginalDate = global.Date;
  const mockNow = Date.UTC(2026, 4, 15, 12, 0, 0); // May 15, 2026

  try {
    global.Date = class extends OriginalDate {
      constructor(...args: any[]) {
        if (args.length === 0) {
          super(mockNow);
        } else {
          super(...(args as []));
        }
      }
      static now() {
        return mockNow;
      }
    } as any;

    costRules.setBudget("key-summary", {
      dailyLimitUsd: 50,
      monthlyLimitUsd: 100,
      warningThreshold: 0.75,
    });

    const now = Date.now();
    const today = now - 1_000;
    const yesterday = now - 24 * 60 * 60 * 1000;
    const lastMonth = new Date();
    lastMonth.setMonth(lastMonth.getMonth() - 1);

    domainState.saveCostEntry("key-summary", 2.5, today);
    domainState.saveCostEntry("key-summary", 1.5, yesterday);
    domainState.saveCostEntry("key-summary", 9.9, lastMonth.getTime());

    assert.equal(costRules.getDailyTotal("key-summary"), 2.5);
    assert.deepEqual(costRules.getCostSummary("key-summary"), {
      dailyTotal: 2.5,
      monthlyTotal: 4,
      totalEntries: 2,
      budget: {
        dailyLimitUsd: 50,
        weeklyLimitUsd: 0,
        monthlyLimitUsd: 100,
        warningThreshold: 0.75,
        resetInterval: "daily",
        resetTime: "00:00",
        budgetResetAt: costRules.getBudget("key-summary")?.budgetResetAt ?? null,
        lastBudgetResetAt: costRules.getBudget("key-summary")?.lastBudgetResetAt ?? null,
        warningEmittedAt: null,
        warningPeriodStart: null,
      },
      totalCostToday: 2.5,
      totalCostMonth: 4,
      totalCostPeriod: 2.5,
      activeLimitUsd: 50,
      resetInterval: "daily",
      resetTime: "00:00",
      budgetResetAt: costRules.getBudget("key-summary")?.budgetResetAt ?? null,
      lastBudgetResetAt: costRules.getBudget("key-summary")?.lastBudgetResetAt ?? null,
      periodStartAt: costRules.getBudget("key-summary")?.lastBudgetResetAt ?? null,
      nextResetAt: costRules.getBudget("key-summary")?.budgetResetAt ?? null,
      dailyLimitUsd: 50,
      weeklyLimitUsd: 0,
      monthlyLimitUsd: 100,
      warningThreshold: 0.75,
    });
  } finally {
    global.Date = OriginalDate;
  }
});

test("costRules covers DB-loaded budgets, malformed entries and storage failure fallbacks", () => {
  domainState.saveBudget("db-loaded", {
    dailyLimitUsd: 7,
    weeklyLimitUsd: 14,
    monthlyLimitUsd: 21,
    warningThreshold: 0.7,
    resetInterval: "weekly",
    resetTime: "06:30",
    budgetResetAt: 111,
    lastBudgetResetAt: 99,
  });
  assert.deepEqual(costRules.getBudget("db-loaded"), {
    dailyLimitUsd: 7,
    weeklyLimitUsd: 14,
    monthlyLimitUsd: 21,
    warningThreshold: 0.7,
    resetInterval: "weekly",
    resetTime: "06:30",
    budgetResetAt: costRules.getBudget("db-loaded")?.budgetResetAt ?? null,
    lastBudgetResetAt: costRules.getBudget("db-loaded")?.lastBudgetResetAt ?? null,
    warningEmittedAt: null,
    warningPeriodStart: null,
  });

  assert.deepEqual(costRules.checkBudget("missing-budget"), {
    allowed: true,
    dailyUsed: 0,
    dailyLimit: 0,
    warningReached: false,
    remaining: 0,
    periodUsed: 0,
    activeLimitUsd: 0,
    resetInterval: null,
    resetTime: null,
    budgetResetAt: null,
    lastBudgetResetAt: null,
    periodStartAt: null,
  });

  const db = core.getDbInstance();
  const now = Date.now();
  db.prepare("INSERT INTO domain_cost_history (api_key_id, cost, timestamp) VALUES (?, ?, ?)").run(
    "malformed-costs",
    "2.25",
    String(now)
  );
  db.prepare("INSERT INTO domain_cost_history (api_key_id, cost, timestamp) VALUES (?, ?, ?)").run(
    "malformed-costs",
    "not-a-number",
    now
  );
  db.prepare("INSERT INTO domain_cost_history (api_key_id, cost, timestamp) VALUES (?, ?, ?)").run(
    "malformed-costs",
    4,
    "not-a-timestamp"
  );

  assert.equal(costRules.getDailyTotal("malformed-costs"), 2.25);
  assert.deepEqual(costRules.getCostSummary("malformed-costs"), {
    dailyTotal: 2.25,
    monthlyTotal: 2.25,
    totalEntries: 1,
    budget: null,
    totalCostToday: 2.25,
    totalCostMonth: 2.25,
    totalCostPeriod: 0,
    activeLimitUsd: 0,
    resetInterval: null,
    resetTime: null,
    budgetResetAt: null,
    lastBudgetResetAt: null,
    periodStartAt: null,
    nextResetAt: null,
    dailyLimitUsd: 0,
    weeklyLimitUsd: 0,
    monthlyLimitUsd: 0,
    warningThreshold: null,
  });

  db.exec("DROP TABLE domain_cost_history");
  assert.equal(costRules.getDailyTotal("malformed-costs"), 0);
  assert.deepEqual(costRules.getCostSummary("malformed-costs"), {
    dailyTotal: 0,
    monthlyTotal: 0,
    totalEntries: 0,
    budget: null,
    totalCostToday: 0,
    totalCostMonth: 0,
    totalCostPeriod: 0,
    activeLimitUsd: 0,
    resetInterval: null,
    resetTime: null,
    budgetResetAt: null,
    lastBudgetResetAt: null,
    periodStartAt: null,
    nextResetAt: null,
    dailyLimitUsd: 0,
    weeklyLimitUsd: 0,
    monthlyLimitUsd: 0,
    warningThreshold: null,
  });
});

test("weekly budgets use the weekly window limit and expose the next reset metadata", () => {
  costRules.setBudget("key-weekly", {
    dailyLimitUsd: 5,
    weeklyLimitUsd: 20,
    resetInterval: "weekly",
    resetTime: "06:30",
  });

  const budget = costRules.getBudget("key-weekly");
  const summary = costRules.getCostSummary("key-weekly");
  const check = costRules.checkBudget("key-weekly", 0);

  assert.equal(budget?.resetInterval, "weekly");
  assert.equal(budget?.resetTime, "06:30");
  assert.equal(summary.activeLimitUsd, 20);
  assert.equal(summary.resetInterval, "weekly");
  assert.equal(check.dailyLimit, 20);
  assert.ok(typeof summary.budgetResetAt === "number" && summary.budgetResetAt > Date.now());
});

test("syncAllBudgetSchedules advances overdue budgets and records a reset log", () => {
  const now = Date.UTC(2026, 3, 17, 12, 0, 0);
  const previousPeriodStart = Date.UTC(2026, 3, 15, 0, 0, 0);
  const overdueResetAt = Date.UTC(2026, 3, 16, 0, 0, 0);
  const originalNow = Date.now;

  try {
    Date.now = () => now;

    domainState.saveBudget("key-reset", {
      dailyLimitUsd: 10,
      warningThreshold: 0.8,
      resetInterval: "daily",
      resetTime: "00:00",
      budgetResetAt: overdueResetAt,
      lastBudgetResetAt: previousPeriodStart,
    });
    domainState.saveCostEntry("key-reset", 3.5, Date.UTC(2026, 3, 15, 12, 0, 0));

    const result = costRules.syncAllBudgetSchedules(now);
    const synced = costRules.getBudget("key-reset");
    const logs = domainState.loadBudgetResetLogs("key-reset", 5);

    assert.equal(result.processed, 1);
    assert.equal(result.resetCount, 1);
    assert.equal(synced?.lastBudgetResetAt, Date.UTC(2026, 3, 17, 0, 0, 0));
    assert.equal(logs.length, 1);
    assert.equal(logs[0].previousSpend, 3.5);
    assert.equal(logs[0].resetInterval, "daily");
  } finally {
    Date.now = originalNow;
  }
});