/**
 * Unit tests for CDP target resolution — no browser and no network required.
 *
 * This is fork-specific logic (see FORK.md): upstream only ever drives a
 * browser on localhost. The precedence here is deliberately asymmetric — an
 * explicitly configured endpoint must never silently fall back to a different
 * browser, while the built-in default must, so a machine off the wire network
 * still gets the local browser the extension was originally written for.
 *
 * Run: npx tsx test/cdp/endpoint-test.ts
 */
import {
  DEFAULT_REMOTE_CDP,
  describeCdpTarget,
  isValidTargetValue,
  resolveCdpTarget,
} from "../../src/cdp/endpoint";

let passed = 0;
let failed = 0;
const check = (cond: boolean, label: string): void => {
  if (cond) {
    passed++;
    console.log(`  ✓ ${label}`);
  } else {
    failed++;
    console.error(`  ✗ ${label}`);
  }
};

const env = (value?: string): NodeJS.ProcessEnv => (value === undefined ? {} : { BU_CDP_HTTP: value });

function main(): void {
  // E1: the built-in default, used when nothing is configured.
  {
    const t = resolveCdpTarget(env());
    check(t.kind === "remote", "E1: unset BU_CDP_HTTP resolves to a remote target");
    if (t.kind === "remote") {
      check(t.source === "default", "E1: it is marked as the built-in default, not an instruction");
      check(`${t.host}:${t.port}` === DEFAULT_REMOTE_CDP, "E1: it matches DEFAULT_REMOTE_CDP");
    }
  }

  // E2: DEFAULT_REMOTE_CDP must itself be parseable, or the default silently
  // degrades to local for everyone.
  {
    const t = resolveCdpTarget(env());
    check(t.kind !== "local", "E2: the built-in default constant is well-formed");
  }

  // E3: an explicit endpoint is an instruction — source must reflect that, so
  // discovery fails loudly rather than falling back.
  {
    const t = resolveCdpTarget(env("10.0.0.9:9333"));
    check(t.kind === "remote", "E3: an explicit host:port resolves to a remote target");
    if (t.kind === "remote") {
      check(t.host === "10.0.0.9" && t.port === 9333, "E3: host and port are parsed");
      check(t.source === "env", "E3: it is marked as explicitly configured");
    }
  }

  // E4: opting back into upstream behaviour.
  for (const alias of ["local", "LOCAL", "off", "none", "0", "no"]) {
    const t = resolveCdpTarget(env(alias));
    check(t.kind === "local", `E4: "${alias}" selects this machine's own browser`);
  }

  // E5: empty or whitespace is treated as unset rather than as an error — a
  // shell exporting an empty var should not break the browser.
  for (const blank of ["", "   "]) {
    const t = resolveCdpTarget(env(blank));
    check(t.kind === "remote" && t.source === "default", `E5: ${JSON.stringify(blank)} falls back to the default`);
  }

  // E6: malformed values are rejected, not coerced. Silently reinterpreting
  // these would drive an unexpected browser.
  for (const bad of ["nonsense", "host:", ":9222", "host:0", "host:70000", "host:abc"]) {
    const t = resolveCdpTarget(env(bad));
    check(t.kind === "invalid", `E6: "${bad}" is rejected as malformed`);
  }

  // E7: IPv6 and hostnames still work — the port is taken from the LAST colon.
  {
    const t = resolveCdpTarget(env("castle.local:9223"));
    check(t.kind === "remote" && t.host === "castle.local", "E7: hostnames are accepted");
    const v6 = resolveCdpTarget(env("[::1]:9223"));
    check(v6.kind === "remote" && v6.host === "[::1]" && v6.port === 9223, "E7: bracketed IPv6 keeps its host");
  }

  // E8: descriptions are for humans in /browser-status; they must distinguish
  // a default from an instruction, since only one of them falls back.
  {
    const d = describeCdpTarget(resolveCdpTarget(env()));
    const e = describeCdpTarget(resolveCdpTarget(env("10.0.0.9:9333")));
    check(d.includes("default"), "E8: the default is labelled as such");
    check(e.includes("BU_CDP_HTTP"), "E8: an explicit endpoint names the variable that set it");
    check(describeCdpTarget(resolveCdpTarget(env("local"))).includes("own browser"), "E8: local is described plainly");
  }

  // E9: the stored choice (/browser-target) sits between env and the default.
  {
    const t = resolveCdpTarget({}, "local");
    check(t.kind === "local" && t.source === "stored", "E9: a stored value is used when the env is unset");

    const r = resolveCdpTarget({}, "10.2.3.4:9224");
    check(r.kind === "remote" && r.source === "stored", "E9: a stored host:port resolves as a remote target");
  }

  // E10: the environment wins, so a one-off `BU_CDP_HTTP=… pi` is never
  // silently overridden by a setting made days ago.
  {
    const t = resolveCdpTarget(env("local"), "10.2.3.4:9224");
    check(t.kind === "local" && t.source === "env", "E10: env beats the stored value");

    const r = resolveCdpTarget(env("10.9.9.9:1234"), "local");
    check(r.kind === "remote" && r.host === "10.9.9.9" && r.source === "env", "E10: an env endpoint beats stored local");
  }

  // E11: clearing the stored value falls back to the built-in default rather
  // than to local — clearing is "use the usual browser", not "go local".
  {
    const t = resolveCdpTarget({}, null);
    check(t.kind === "remote" && t.source === "default", "E11: no stored value falls back to the default");
    const blank = resolveCdpTarget({}, "   ");
    check(blank.kind === "remote" && blank.source === "default", "E11: a blank stored value is treated as cleared");
  }

  // E12: a corrupt stored value must be reported against the right source, or
  // the operator goes hunting through their shell config for an env var that
  // was never set.
  {
    const t = resolveCdpTarget({}, "garbage");
    check(t.kind === "invalid" && t.source === "stored", "E12: a bad stored value is blamed on /browser-target");
    if (t.kind === "invalid") {
      check(describeCdpTarget(t).includes("/browser-target"), "E12: the description names the stored source");
    }
    const e = resolveCdpTarget(env("garbage"), null);
    check(e.kind === "invalid" && e.source === "env", "E12: a bad env value is blamed on BU_CDP_HTTP");
  }

  // E13: the values /browser-target accepts must match what resolution can
  // actually use, or the command would happily store something unusable.
  {
    for (const good of ["local", "off", "1.2.3.4:9222", "castle.local:9223"]) {
      check(isValidTargetValue(good), `E13: "${good}" is accepted by the command`);
    }
    for (const bad of ["", "  ", "garbage", "host:", "host:99999"]) {
      check(!isValidTargetValue(bad), `E13: "${bad}" is rejected by the command`);
    }
    check(!isValidTargetValue("default"), "E13: \"default\" is handled as clear, not stored verbatim");
  }

  console.log(`\n${passed} passed, ${failed} failed`);
  if (failed > 0) process.exit(1);
}

main();