import {
  CONFIG_PATH_CLAWDBOT,
  parseConfigJson5,
  readConfigFileSnapshot,
  validateConfigObject,
  writeConfigFile,
} from "../../config/config.js";
import { buildConfigSchema } from "../../config/schema.js";
import { scheduleGatewaySigusr1Restart } from "../../infra/restart.js";
import {
  type RestartSentinelPayload,
  writeRestartSentinel,
} from "../../infra/restart-sentinel.js";
import {
  ErrorCodes,
  errorShape,
  formatValidationErrors,
  validateConfigApplyParams,
  validateConfigGetParams,
  validateConfigSchemaParams,
  validateConfigSetParams,
} from "../protocol/index.js";
import type { GatewayRequestHandlers } from "./types.js";

export const configHandlers: GatewayRequestHandlers = {
  "config.get": async ({ params, respond }) => {
    if (!validateConfigGetParams(params)) {
      respond(
        false,
        undefined,
        errorShape(
          ErrorCodes.INVALID_REQUEST,
          `invalid config.get params: ${formatValidationErrors(validateConfigGetParams.errors)}`,
        ),
      );
      return;
    }
    const snapshot = await readConfigFileSnapshot();
    respond(true, snapshot, undefined);
  },
  "config.schema": ({ params, respond }) => {
    if (!validateConfigSchemaParams(params)) {
      respond(
        false,
        undefined,
        errorShape(
          ErrorCodes.INVALID_REQUEST,
          `invalid config.schema params: ${formatValidationErrors(validateConfigSchemaParams.errors)}`,
        ),
      );
      return;
    }
    const schema = buildConfigSchema();
    respond(true, schema, undefined);
  },
  "config.set": async ({ params, respond }) => {
    if (!validateConfigSetParams(params)) {
      respond(
        false,
        undefined,
        errorShape(
          ErrorCodes.INVALID_REQUEST,
          `invalid config.set params: ${formatValidationErrors(validateConfigSetParams.errors)}`,
        ),
      );
      return;
    }
    const rawValue = (params as { raw?: unknown }).raw;
    if (typeof rawValue !== "string") {
      respond(
        false,
        undefined,
        errorShape(
          ErrorCodes.INVALID_REQUEST,
          "invalid config.set params: raw (string) required",
        ),
      );
      return;
    }
    const parsedRes = parseConfigJson5(rawValue);
    if (!parsedRes.ok) {
      respond(
        false,
        undefined,
        errorShape(ErrorCodes.INVALID_REQUEST, parsedRes.error),
      );
      return;
    }
    const validated = validateConfigObject(parsedRes.parsed);
    if (!validated.ok) {
      respond(
        false,
        undefined,
        errorShape(ErrorCodes.INVALID_REQUEST, "invalid config", {
          details: { issues: validated.issues },
        }),
      );
      return;
    }
    await writeConfigFile(validated.config);
    respond(
      true,
      {
        ok: true,
        path: CONFIG_PATH_CLAWDBOT,
        config: validated.config,
      },
      undefined,
    );
  },
  "config.apply": async ({ params, respond }) => {
    if (!validateConfigApplyParams(params)) {
      respond(
        false,
        undefined,
        errorShape(
          ErrorCodes.INVALID_REQUEST,
          `invalid config.apply params: ${formatValidationErrors(validateConfigApplyParams.errors)}`,
        ),
      );
      return;
    }
    const rawValue = (params as { raw?: unknown }).raw;
    if (typeof rawValue !== "string") {
      respond(
        false,
        undefined,
        errorShape(
          ErrorCodes.INVALID_REQUEST,
          "invalid config.apply params: raw (string) required",
        ),
      );
      return;
    }
    const parsedRes = parseConfigJson5(rawValue);
    if (!parsedRes.ok) {
      respond(
        false,
        undefined,
        errorShape(ErrorCodes.INVALID_REQUEST, parsedRes.error),
      );
      return;
    }
    const validated = validateConfigObject(parsedRes.parsed);
    if (!validated.ok) {
      respond(
        false,
        undefined,
        errorShape(ErrorCodes.INVALID_REQUEST, "invalid config", {
          details: { issues: validated.issues },
        }),
      );
      return;
    }
    await writeConfigFile(validated.config);

    const sessionKey =
      typeof (params as { sessionKey?: unknown }).sessionKey === "string"
        ? (params as { sessionKey?: string }).sessionKey?.trim() || undefined
        : undefined;
    const note =
      typeof (params as { note?: unknown }).note === "string"
        ? (params as { note?: string }).note?.trim() || undefined
        : undefined;
    const restartDelayMsRaw = (params as { restartDelayMs?: unknown })
      .restartDelayMs;
    const restartDelayMs =
      typeof restartDelayMsRaw === "number" &&
      Number.isFinite(restartDelayMsRaw)
        ? Math.max(0, Math.floor(restartDelayMsRaw))
        : undefined;

    const payload: RestartSentinelPayload = {
      kind: "config-apply",
      status: "ok",
      ts: Date.now(),
      sessionKey,
      message: note ?? null,
      stats: {
        mode: "config.apply",
        root: CONFIG_PATH_CLAWDBOT,
      },
    };
    let sentinelPath: string | null = null;
    try {
      sentinelPath = await writeRestartSentinel(payload);
    } catch {
      sentinelPath = null;
    }
    const restart = scheduleGatewaySigusr1Restart({
      delayMs: restartDelayMs,
      reason: "config.apply",
    });
    respond(
      true,
      {
        ok: true,
        path: CONFIG_PATH_CLAWDBOT,
        config: validated.config,
        restart,
        sentinel: {
          path: sentinelPath,
          payload,
        },
      },
      undefined,
    );
  },
};