// Runs one ordered agent profile. Credential decryption and reviewer posting
// live in separate processes so neither privileged secret reaches this runner.
import { TextLineStream } from "jsr:@std/streams@1/text-line-stream";
import {
  type CodexAuthentication,
  codexAuthentication,
  persistCodexAuth,
  retryInvalidToken,
  stageCodexAuth,
} from "./auth.ts";
import {
  agentCommand,
  killProfileProcesses,
  readProfileFile,
} from "./isolation.ts";
import {
  agentEnvironment,
  runProfiles,
  sanitizedEnvironment,
  withProfile,
} from "./profiles.ts";
import {
  collectOpenCodeOutput,
  openCodeArgs,
  parseOpenCodeEvents,
} from "./opencode.ts";
import {
  readRuntimeManifest,
  type RuntimeOutcome,
  type RuntimeProfile,
} from "./runtime.ts";

type GiteaUser = { login: string; email: string };
type GiteaComment = { user: GiteaUser; created_at: string; body: string };
type AttemptResult = {
  body: string;
  reviewPath: string;
  anchorsPath: string;
  profile: Pick<RuntimeProfile, "type" | "model">;
};

const env = (name: string): string => {
  const value = Deno.env.get(name);
  if (value === undefined) throw new Error(`${name} is not set`);
  return value;
};

const API = env("GITEA_API_URL");
const REPO = env("GITEA_REPOSITORY");
const INDEX = env("ISSUE_INDEX");
const EVENT = env("EVENT_NAME");
const AUTHOR_TOKEN = env("GITEA_TOKEN");
const WORKSPACE = env("GITHUB_WORKSPACE");
const MANIFEST = await readRuntimeManifest(env("BOT_AGENTS_MANIFEST"));
const PROCESS_ENV = sanitizedEnvironment(Deno.env.toObject());
const RULES_PATH = "repos/commons/code-rules/raw/README.md";
const CODEX_AUTH = "/root/.codex/auth.json";
const SKILLS_INSTALL = "skills add obra/superpowers";

async function gitea(path: string, body?: unknown): Promise<Response> {
  const response = await fetch(`${API}/${path}`, {
    method: body === undefined ? "GET" : "POST",
    headers: {
      Authorization: `token ${AUTHOR_TOKEN}`,
      "Content-Type": "application/json",
    },
    body: body === undefined ? undefined : JSON.stringify(body),
  });
  if (!response.ok) {
    throw new Error(`${path}: ${response.status} ${await response.text()}`);
  }
  return response;
}

async function postAuthorComment(body: string): Promise<void> {
  await gitea(`repos/${REPO}/issues/${INDEX}/comments`, { body });
}

async function runRoot(command: string, args: string[]): Promise<void> {
  const { success, code } = await new Deno.Command(command, {
    args,
    env: PROCESS_ENV,
    clearEnv: true,
  }).output();
  if (!success) throw new Error(`${command} ${args[0]} exited with ${code}`);
}

async function configureGitAuthor(): Promise<void> {
  const user: GiteaUser = await (await gitea("user")).json();
  for (const [key, value] of [["name", user.login], ["email", user.email]]) {
    await runRoot("git", ["config", `user.${key}`, value]);
  }
}

async function readProfileToken(
  profile: RuntimeProfile,
): Promise<string | undefined> {
  return profile.tokenFile === null
    ? undefined
    : await Deno.readTextFile(profile.tokenFile);
}

async function runAgentCommand(
  profile: RuntimeProfile,
  command: string,
  args: string[],
  token?: string,
): Promise<void> {
  const { success, code } = await agentCommand(profile, command, args, {
    cwd: WORKSPACE,
    env: agentEnvironment(PROCESS_ENV, profile, token),
    clearEnv: true,
  }).output();
  if (!success) throw new Error(`${command} ${args[0]} exited with ${code}`);
}

async function prepareProfile(
  profile: RuntimeProfile,
): Promise<void> {
  await runAgentCommand(profile, "git", [
    "config",
    "--global",
    "--add",
    "safe.directory",
    WORKSPACE,
  ]);
  await runAgentCommand(profile, "npx", [
    "-y",
    ...SKILLS_INSTALL.split(" "),
    "--global",
    "--agent",
    profile.type === "claude" ? "claude-code" : profile.type,
    "--yes",
  ]);
}

async function renderPrompt(
  profile: RuntimeProfile,
): Promise<{ prompt: string; reviewPath: string; anchorsPath: string }> {
  const reviewPath = await makeProfileFile(profile, "review.md");
  const anchorsPath = await makeProfileFile(profile, "anchors.json");
  const comments: GiteaComment[] = await (await gitea(
    `repos/${REPO}/issues/${INDEX}/comments?limit=100`,
  )).json();
  const values: Record<string, string> = {
    COMMENT: env("COMMENT"),
    ISSUE_COMMENTS: comments
      .map((comment) =>
        `## ${comment.user.login} at ${comment.created_at}\n\n${comment.body}\n`
      )
      .join("\n"),
    CODE_RULES: await (await gitea(RULES_PATH)).text(),
    EVENT_NAME: EVENT,
    GITEA_API_URL: API,
    GITEA_REPOSITORY: REPO,
    ISSUE_INDEX: INDEX,
    REVIEW_PATH: reviewPath,
    ANCHORS_PATH: anchorsPath,
  };
  const template = await Deno.readTextFile(
    new URL("../prompt.md", import.meta.url),
  );
  return {
    prompt: template.replace(
      /\$\{(\w+)\}/g,
      (match, name) => values[name] ?? match,
    ),
    reviewPath,
    anchorsPath,
  };
}

async function runClaude(
  profile: RuntimeProfile,
  token: string,
  prompt: string,
): Promise<string> {
  const claude = agentCommand(profile, "claude", [
    "--print",
    "--dangerously-skip-permissions",
    "--model",
    profile.model,
    "--output-format",
    "stream-json",
    "--verbose",
    prompt,
  ], {
    cwd: WORKSPACE,
    env: {
      ...agentEnvironment(PROCESS_ENV, profile, token),
      IS_SANDBOX: "1",
    },
    clearEnv: true,
    stdout: "piped",
    stderr: "piped",
  }).spawn();
  let result:
    | { is_error?: boolean; result?: string; subtype: string }
    | undefined;
  let error = "";
  const copyError = claude.stderr.pipeThrough(new TextDecoderStream()).pipeTo(
    new WritableStream({
      write(chunk) {
        error += chunk;
        console.error(chunk);
      },
    }),
  );
  const lines = claude.stdout
    .pipeThrough(new TextDecoderStream())
    .pipeThrough(new TextLineStream());
  for await (const line of lines) {
    if (!line) continue;
    const event = JSON.parse(line);
    for (const part of event.message?.content ?? []) {
      const text = part.thinking ?? part.text ?? part.name;
      if (text) console.log(text);
    }
    if (event.type === "result") result = event;
  }
  const [status] = await Promise.all([claude.status, copyError]);
  if (result?.is_error) {
    throw new Error(result.result ?? `claude ended with ${result.subtype}`);
  }
  if (result?.result === undefined) {
    throw new Error(
      error.trim() || `claude ended with ${result?.subtype ?? "no result"}`,
    );
  }
  if (!status.success) {
    throw new Error(error.trim() || `claude exited with ${status.code}`);
  }
  return result.result;
}

async function codexDeviceLogin(
  profile: RuntimeProfile,
  environment: Record<string, string>,
): Promise<void> {
  const login = agentCommand(profile, "codex", ["login", "--device-auth"], {
    cwd: WORKSPACE,
    env: environment,
    clearEnv: true,
    stdout: "piped",
    stderr: "piped",
  }).spawn();
  let shown = "";
  const collect = (stream: ReadableStream<Uint8Array>): Promise<void> =>
    stream.pipeThrough(new TextDecoderStream()).pipeTo(
      new WritableStream({ write: (chunk) => void (shown += chunk) }),
    );
  const drained = Promise.all([collect(login.stdout), collect(login.stderr)]);
  const status = login.status;
  await new Promise((resolve) => setTimeout(resolve, 3000));
  while (shown.trim() === "") {
    const exited = await Promise.race([
      status.then(() => true),
      new Promise<boolean>((resolve) => setTimeout(() => resolve(false), 100)),
    ]);
    if (exited) throw new Error("AI bot login produced no instructions");
  }
  await postAuthorComment(withProfile(shown, profile));
  const [result] = await Promise.all([status, drained]);
  if (!result.success) {
    throw new Error(`codex login exited with ${result.code}`);
  }
}

async function codexApiLogin(
  profile: RuntimeProfile,
  environment: Record<string, string>,
  token: string,
): Promise<void> {
  const login = agentCommand(profile, "codex", ["login", "--with-api-key"], {
    cwd: WORKSPACE,
    env: environment,
    clearEnv: true,
    stdin: "piped",
    stderr: "piped",
  }).spawn();
  const writer = login.stdin.getWriter();
  await writer.write(new TextEncoder().encode(`${token}\n`));
  await writer.close();
  const [status, error] = await Promise.all([
    login.status,
    new Response(login.stderr).text(),
  ]);
  if (!status.success) {
    throw new Error(error.trim() || `codex login exited with ${status.code}`);
  }
}

async function makeProfileFile(
  profile: RuntimeProfile,
  name: string,
): Promise<string> {
  const path = `${profile.home}/${name}`;
  await Deno.writeTextFile(path, "", { mode: 0o600 });
  await Deno.chmod(path, 0o600);
  await Deno.chown(path, profile.uid, profile.gid);
  return path;
}

async function runCodex(
  profile: RuntimeProfile,
  prompt: string,
  authentication: CodexAuthentication,
): Promise<string> {
  const token = authentication.kind === "api-key"
    ? authentication.token
    : undefined;
  const environment = agentEnvironment(PROCESS_ENV, profile, token);
  if (authentication.kind === "api-key") {
    await codexApiLogin(profile, environment, authentication.token);
  } else {
    const loggedIn = await agentCommand(profile, "codex", [
      "login",
      "status",
    ], {
      cwd: WORKSPACE,
      env: environment,
      clearEnv: true,
    }).output();
    if (!loggedIn.success) await codexDeviceLogin(profile, environment);
  }
  const outputPath = await makeProfileFile(profile, "result.md");
  const attempt = async () => {
    const codex = agentCommand(profile, "codex", [
      "exec",
      "--model",
      profile.model,
      "--dangerously-bypass-approvals-and-sandbox",
      "--output-last-message",
      outputPath,
      prompt,
    ], {
      cwd: WORKSPACE,
      env: environment,
      clearEnv: true,
      stdout: "inherit",
      stderr: "piped",
    }).spawn();
    const decoder = new TextDecoder();
    let error = "";
    for await (const chunk of codex.stderr) {
      await Deno.stderr.write(chunk);
      error += decoder.decode(chunk, { stream: true });
    }
    error += decoder.decode();
    return { status: await codex.status, error };
  };
  const result = authentication.kind === "api-key"
    ? await attempt()
    : await retryInvalidToken(attempt, async () => {
      await runAgentCommand(profile, "codex", ["logout"]);
      await codexDeviceLogin(profile, environment);
    });
  if (!result.status.success) {
    throw new Error(
      result.error.trim() || `codex exited with ${result.status.code}`,
    );
  }
  return outputPath;
}

async function runOpenCode(
  profile: RuntimeProfile,
  token: string,
  prompt: string,
): Promise<string> {
  const process = agentCommand(
    profile,
    "opencode",
    openCodeArgs(profile.model, prompt),
    {
      cwd: WORKSPACE,
      env: agentEnvironment(PROCESS_ENV, profile, token),
      clearEnv: true,
      stdout: "piped",
      stderr: "piped",
    },
  ).spawn();
  const output = collectOpenCodeOutput(
    process.stdout,
    process.stderr,
    async (chunk) => {
      await Deno.stdout.write(chunk);
    },
    async (chunk) => {
      await Deno.stderr.write(chunk);
    },
  );
  const [status, streams] = await Promise.all([process.status, output]);
  const error = streams.stderr.trim();
  if (!status.success) {
    throw new Error(error || `opencode exited with ${status.code}`);
  }
  return parseOpenCodeEvents(streams.stdout);
}

async function runProfile(profile: RuntimeProfile): Promise<AttemptResult> {
  const token = await readProfileToken(profile);
  const authentication = profile.type === "codex"
    ? codexAuthentication(token)
    : null;
  let stagedCodexAuth: string | null = null;
  let body: string | undefined;
  let resultPath: string | null = null;
  let reviewPath: string | undefined;
  let anchorsPath: string | undefined;
  try {
    if (authentication?.kind === "persistent") {
      stagedCodexAuth = await stageCodexAuth(
        CODEX_AUTH,
        profile.home,
        profile.uid,
        profile.gid,
      );
    }
    await prepareProfile(profile);
    const rendered = await renderPrompt(profile);
    reviewPath = rendered.reviewPath;
    anchorsPath = rendered.anchorsPath;
    if (profile.type === "claude") {
      body = await runClaude(profile, token ?? "", rendered.prompt);
    } else if (profile.type === "codex") {
      resultPath = await runCodex(profile, rendered.prompt, authentication!);
    } else {
      body = await runOpenCode(profile, token ?? "", rendered.prompt);
    }
  } finally {
    await killProfileProcesses(profile.uid);
    if (stagedCodexAuth !== null) {
      await persistCodexAuth(stagedCodexAuth, CODEX_AUTH);
    }
  }
  if (resultPath !== null) body = await readProfileFile(profile, resultPath);
  if (
    body === undefined || reviewPath === undefined || anchorsPath === undefined
  ) {
    throw new Error("agent attempt produced no result");
  }
  return {
    body,
    reviewPath,
    anchorsPath,
    profile: { type: profile.type, model: profile.model },
  };
}

async function writeOutcome(outcome: RuntimeOutcome): Promise<void> {
  await Deno.writeTextFile(MANIFEST.outcomeFile, JSON.stringify(outcome), {
    mode: 0o600,
  });
  await Deno.chmod(MANIFEST.outcomeFile, 0o600);
}

try {
  await configureGitAuthor();
  await writeOutcome({
    ok: true,
    ...await runProfiles(MANIFEST.profiles, runProfile),
  });
} catch (error) {
  console.error(error);
  await writeOutcome({ ok: false });
  throw error;
}