// ACPX doctor contract migrates shipped plugin-owned runtime state.
import fs from "node:fs/promises";
import path from "node:path";
import {
  archiveLegacyStateSource,
  type PluginDoctorStateMigration,
} from "openclaw/plugin-sdk/runtime-doctor";
import {
  normalizeAcpxProcessLease,
  normalizeAcpxProcessLeaseFile,
  openAcpxProcessLeaseStateStore,
  type AcpxProcessLease,
} from "./src/process-lease.js";
import {
  ACPX_GATEWAY_INSTANCE_KEY,
  ACPX_GATEWAY_INSTANCE_MAX_ENTRIES,
  ACPX_GATEWAY_INSTANCE_NAMESPACE,
  ACPX_LEGACY_GATEWAY_INSTANCE_FILE,
  ACPX_LEGACY_PROCESS_LEASE_FILE,
  normalizeAcpxGatewayInstanceRecord,
  type AcpxGatewayInstanceRecord,
} from "./src/state.js";

function resolveLegacyGatewayInstancePath(stateDir: string): string {
  return path.join(stateDir, ACPX_LEGACY_GATEWAY_INSTANCE_FILE);
}

function resolveLegacyProcessLeasePath(stateDir: string): string {
  return path.join(stateDir, "acpx", ACPX_LEGACY_PROCESS_LEASE_FILE);
}

async function readLegacyGatewayInstanceId(filePath: string): Promise<string | null> {
  try {
    const value = (await fs.readFile(filePath, "utf8")).trim();
    return value || null;
  } catch {
    return null;
  }
}

async function readLegacyOpenProcessLeases(filePath: string): Promise<AcpxProcessLease[]> {
  try {
    const leaseFile = normalizeAcpxProcessLeaseFile(
      JSON.parse(await fs.readFile(filePath, "utf8")),
    );
    return leaseFile.leases.filter((lease) => lease.state === "open" || lease.state === "closing");
  } catch {
    return [];
  }
}

export const stateMigrations: PluginDoctorStateMigration[] = [
  {
    id: "acpx-runtime-state-to-plugin-state",
    label: "ACPX runtime state",
    async detectLegacyState(params) {
      const gatewayInstanceId = await readLegacyGatewayInstanceId(
        resolveLegacyGatewayInstancePath(params.stateDir),
      );
      const openLeases = await readLegacyOpenProcessLeases(
        resolveLegacyProcessLeasePath(params.stateDir),
      );
      if (!gatewayInstanceId && openLeases.length === 0) {
        return null;
      }
      const preview: string[] = [];
      if (gatewayInstanceId) {
        preview.push(
          `- ACPX gateway instance id: ${resolveLegacyGatewayInstancePath(params.stateDir)} -> plugin state (${ACPX_GATEWAY_INSTANCE_NAMESPACE})`,
        );
      }
      if (openLeases.length > 0) {
        preview.push(
          `- ACPX process leases: ${resolveLegacyProcessLeasePath(params.stateDir)} -> plugin state (${openLeases.length} open lease(s))`,
        );
      }
      return { preview };
    },
    async migrateLegacyState(params) {
      const changes: string[] = [];
      const warnings: string[] = [];
      const gatewayInstancePath = resolveLegacyGatewayInstancePath(params.stateDir);
      const gatewayInstanceId = await readLegacyGatewayInstanceId(gatewayInstancePath);
      const processLeasePath = resolveLegacyProcessLeasePath(params.stateDir);
      const openLeases = await readLegacyOpenProcessLeases(processLeasePath);
      const processLeaseStore = openAcpxProcessLeaseStateStore(
        params.context.openPluginStateKeyedStore,
      );
      const gatewayStore = params.context.openPluginStateKeyedStore<AcpxGatewayInstanceRecord>({
        namespace: ACPX_GATEWAY_INSTANCE_NAMESPACE,
        maxEntries: ACPX_GATEWAY_INSTANCE_MAX_ENTRIES,
      });
      const existingGateway = normalizeAcpxGatewayInstanceRecord(
        await gatewayStore.lookup(ACPX_GATEWAY_INSTANCE_KEY),
      );
      const existingLiveLeases = (await processLeaseStore.entries())
        .map((entry) => normalizeAcpxProcessLease(entry.value))
        .filter(
          (lease): lease is AcpxProcessLease =>
            lease != null && (lease.state === "open" || lease.state === "closing"),
        );
      const leaseGatewayIds = new Set(openLeases.map((lease) => lease.gatewayInstanceId));
      const onlyLeaseGatewayId = leaseGatewayIds.size === 1 ? [...leaseGatewayIds][0] : null;
      const canAdoptLegacyGateway =
        existingGateway &&
        gatewayInstanceId &&
        existingGateway.instanceId !== gatewayInstanceId &&
        onlyLeaseGatewayId === gatewayInstanceId &&
        existingLiveLeases.length === 0;
      const canonicalGatewayInstanceId =
        canAdoptLegacyGateway || !existingGateway
          ? (gatewayInstanceId ?? onlyLeaseGatewayId)
          : existingGateway.instanceId;

      if (
        openLeases.length > 0 &&
        (!canonicalGatewayInstanceId ||
          [...leaseGatewayIds].some(
            (leaseGatewayId) => leaseGatewayId !== canonicalGatewayInstanceId,
          ))
      ) {
        warnings.push(
          "Skipped ACPX process lease migration because legacy leases do not match the canonical gateway instance id; left legacy sources in place for manual cleanup",
        );
        return { changes, warnings };
      }

      if (canAdoptLegacyGateway && canonicalGatewayInstanceId) {
        await gatewayStore.register(ACPX_GATEWAY_INSTANCE_KEY, {
          instanceId: canonicalGatewayInstanceId,
          createdAt: Date.now(),
        });
        changes.push("Migrated ACPX gateway instance id -> plugin state");
      } else if (canonicalGatewayInstanceId && !existingGateway) {
        await gatewayStore.register(ACPX_GATEWAY_INSTANCE_KEY, {
          instanceId: canonicalGatewayInstanceId,
          createdAt: Date.now(),
        });
        changes.push("Migrated ACPX gateway instance id -> plugin state");
      } else if (gatewayInstanceId && existingGateway?.instanceId !== gatewayInstanceId) {
        warnings.push(
          "Skipped ACPX gateway instance id import because plugin state already differs",
        );
      }

      if (gatewayInstanceId) {
        await archiveLegacyStateSource({
          filePath: gatewayInstancePath,
          label: "ACPX gateway-instance-id",
          changes,
          warnings,
        });
      }

      if (openLeases.length > 0) {
        let imported = 0;
        let alreadyPresent = 0;
        for (const lease of openLeases) {
          const inserted = await processLeaseStore.registerIfAbsent(lease.leaseId, lease);
          if (inserted) {
            imported++;
          } else {
            alreadyPresent++;
          }
        }
        changes.push(
          `Migrated ACPX process leases -> plugin state (${imported} imported, ${alreadyPresent} already present)`,
        );
        await archiveLegacyStateSource({
          filePath: processLeasePath,
          label: "ACPX process-leases",
          changes,
          warnings,
        });
      }

      return { changes, warnings };
    },
  },
];