import { and, eq } from "drizzle-orm";
import {
  assertCircuitDeviceRowUpdateProjectCommand,
  createCircuitDeviceRowUpdateProjectCommand,
  type CircuitDeviceRowUpdateField,
  type CircuitDeviceRowUpdatePatch,
  type CircuitDeviceRowUpdateValues,
} from "../../domain/models/circuit-device-row-project-command.model.js";
import type {
  CircuitDeviceRowProjectCommandStore,
  ExecuteCircuitDeviceRowUpdateCommandInput,
} from "../../domain/ports/circuit-device-row-project-command.store.js";
import { deriveOverriddenFieldsForLocalEdit } from "../../domain/services/project-device-overrides.js";
import type { AppDatabase } from "../database-context.js";
import { circuitDeviceRows } from "../schema/circuit-device-rows.js";
import { circuitLists } from "../schema/circuit-lists.js";
import { circuits } from "../schema/circuits.js";
import { projectDevices } from "../schema/project-devices.js";
import { rooms } from "../schema/rooms.js";
import {
  toCircuitDeviceRowPatchValues,
  type CircuitDeviceRowPatchInput,
} from "./circuit-device-row.persistence.js";
import { executeProjectCommandTransactionWithAppliedForward } from "./project-command-transaction.persistence.js";
import { updateDerivedCircuitVoltage } from "./project-voltage.persistence.js";

type CircuitDeviceRow = typeof circuitDeviceRows.$inferSelect;

export class CircuitDeviceRowProjectCommandRepository
  implements CircuitDeviceRowProjectCommandStore
{
  constructor(private readonly database: AppDatabase) {}

  executeUpdate(input: ExecuteCircuitDeviceRowUpdateCommandInput) {
    assertCircuitDeviceRowUpdateProjectCommand(input.command);

    return executeProjectCommandTransactionWithAppliedForward(
      this.database,
      input,
      (tx) => this.applyCommand(tx, input)
    );
  }

  private applyCommand(
    tx: AppDatabase,
    input: ExecuteCircuitDeviceRowUpdateCommandInput
  ) {
    const current = tx
      .select()
      .from(circuitDeviceRows)
      .where(eq(circuitDeviceRows.id, input.command.payload.rowId))
      .get();
    if (!current) {
      throw new Error("Invalid device row id.");
    }

    const circuit = tx
      .select({ circuitListId: circuits.circuitListId })
      .from(circuits)
      .where(eq(circuits.id, current.circuitId))
      .get();
    const owningList = circuit
      ? tx
          .select({ id: circuitLists.id })
          .from(circuitLists)
          .where(
            and(
              eq(circuitLists.id, circuit.circuitListId),
              eq(circuitLists.projectId, input.projectId)
            )
          )
          .get()
      : null;
    if (!owningList) {
      throw new Error("Circuit device row does not belong to project.");
    }

    const patch = Object.fromEntries(
      input.command.payload.changes.map((change) => [
        change.field,
        change.value,
      ])
    ) as CircuitDeviceRowPatchInput;
    this.assertLinkedProjectDevice(tx, input.projectId, patch);
    this.assertRoom(tx, input.projectId, patch);

    const overriddenFields = deriveOverriddenFieldsForLocalEdit(
      current,
      patch
    );
    if (
      overriddenFields !== undefined &&
      patch.overriddenFields === undefined
    ) {
      patch.overriddenFields = overriddenFields;
    }

    const appliedForward = createCircuitDeviceRowUpdateProjectCommand(
      current.id,
      patch as CircuitDeviceRowUpdatePatch
    );
    const inversePatch = Object.fromEntries(
      appliedForward.payload.changes.map((change) => [
        change.field,
        getCircuitDeviceRowFieldValue(current, change.field),
      ])
    ) as CircuitDeviceRowUpdatePatch;
    const inverse = createCircuitDeviceRowUpdateProjectCommand(
      current.id,
      inversePatch
    );

    const update = tx
      .update(circuitDeviceRows)
      .set(toCircuitDeviceRowPatchValues(patch))
      .where(eq(circuitDeviceRows.id, current.id))
      .run();
    if (update.changes !== 1) {
      throw new Error("Circuit device row changed before command execution.");
    }
    if (patch.phaseType !== undefined) {
      updateDerivedCircuitVoltage(
        tx,
        input.projectId,
        current.circuitId
      );
    }

    return {
      forward: appliedForward,
      inverse,
    };
  }

  private assertLinkedProjectDevice(
    database: AppDatabase,
    projectId: string,
    patch: CircuitDeviceRowPatchInput
  ) {
    if (
      !Object.prototype.hasOwnProperty.call(patch, "linkedProjectDeviceId") ||
      patch.linkedProjectDeviceId === null ||
      patch.linkedProjectDeviceId === undefined
    ) {
      return;
    }
    const device = database
      .select({ id: projectDevices.id })
      .from(projectDevices)
      .where(
        and(
          eq(projectDevices.id, patch.linkedProjectDeviceId),
          eq(projectDevices.projectId, projectId)
        )
      )
      .get();
    if (!device) {
      throw new Error("Invalid linked project device id.");
    }
  }

  private assertRoom(
    database: AppDatabase,
    projectId: string,
    patch: CircuitDeviceRowPatchInput
  ) {
    if (
      !Object.prototype.hasOwnProperty.call(patch, "roomId") ||
      patch.roomId === null ||
      patch.roomId === undefined
    ) {
      return;
    }
    const room = database
      .select({ id: rooms.id })
      .from(rooms)
      .where(and(eq(rooms.id, patch.roomId), eq(rooms.projectId, projectId)))
      .get();
    if (!room) {
      throw new Error("Invalid room id.");
    }
  }
}

function getCircuitDeviceRowFieldValue<
  TField extends CircuitDeviceRowUpdateField,
>(
  row: CircuitDeviceRow,
  field: TField
): CircuitDeviceRowUpdateValues[TField] {
  return row[field] as unknown as CircuitDeviceRowUpdateValues[TField];
}