import crypto from "node:crypto";
import { asc, eq } from "drizzle-orm";
import {
  parseProjectStateSnapshot,
  projectStateSnapshotSchemaVersion,
  serializeProjectStateSnapshot,
  type ProjectStateSnapshot,
} from "../../domain/models/project-state-snapshot.model.js";
import type { AppDatabase } from "../database-context.js";
import { circuitDeviceRows } from "../schema/circuit-device-rows.js";
import { circuitLists } from "../schema/circuit-lists.js";
import { circuitSections } from "../schema/circuit-sections.js";
import { circuits } from "../schema/circuits.js";
import { distributionBoards } from "../schema/distribution-boards.js";
import { floors } from "../schema/floors.js";
import { projectDevices } from "../schema/project-devices.js";
import { projects } from "../schema/projects.js";
import { rooms } from "../schema/rooms.js";

export interface PersistedProjectStateSnapshot {
  currentRevision: number;
  state: ProjectStateSnapshot;
  payloadJson: string;
  payloadSha256: string;
}

export function readProjectStateSnapshot(
  database: AppDatabase,
  projectId: string
): PersistedProjectStateSnapshot | null {
  const project = database
    .select({
      id: projects.id,
      name: projects.name,
      singlePhaseVoltageV: projects.singlePhaseVoltageV,
      threePhaseVoltageV: projects.threePhaseVoltageV,
      currentRevision: projects.currentRevision,
    })
    .from(projects)
    .where(eq(projects.id, projectId))
    .get();
  if (!project) {
    return null;
  }

  const boardRows = database
    .select()
    .from(distributionBoards)
    .where(eq(distributionBoards.projectId, projectId))
    .orderBy(asc(distributionBoards.name), asc(distributionBoards.id))
    .all();
  const listRows = database
    .select()
    .from(circuitLists)
    .where(eq(circuitLists.projectId, projectId))
    .orderBy(asc(circuitLists.name), asc(circuitLists.id))
    .all();
  const sectionRows = database
    .select({
      id: circuitSections.id,
      circuitListId: circuitSections.circuitListId,
      key: circuitSections.key,
      displayName: circuitSections.displayName,
      prefix: circuitSections.prefix,
      sortOrder: circuitSections.sortOrder,
    })
    .from(circuitSections)
    .innerJoin(
      circuitLists,
      eq(circuitLists.id, circuitSections.circuitListId)
    )
    .where(eq(circuitLists.projectId, projectId))
    .orderBy(
      asc(circuitSections.circuitListId),
      asc(circuitSections.sortOrder),
      asc(circuitSections.id)
    )
    .all();
  const circuitRows = database
    .select({
      id: circuits.id,
      circuitListId: circuits.circuitListId,
      sectionId: circuits.sectionId,
      equipmentIdentifier: circuits.equipmentIdentifier,
      displayName: circuits.displayName,
      sortOrder: circuits.sortOrder,
      protectionType: circuits.protectionType,
      protectionRatedCurrent: circuits.protectionRatedCurrent,
      protectionCharacteristic: circuits.protectionCharacteristic,
      cableType: circuits.cableType,
      cableCrossSection: circuits.cableCrossSection,
      cableLength: circuits.cableLength,
      rcdAssignment: circuits.rcdAssignment,
      terminalDesignation: circuits.terminalDesignation,
      voltage: circuits.voltage,
      controlRequirement: circuits.controlRequirement,
      status: circuits.status,
      isReserve: circuits.isReserve,
      remark: circuits.remark,
    })
    .from(circuits)
    .innerJoin(circuitLists, eq(circuitLists.id, circuits.circuitListId))
    .where(eq(circuitLists.projectId, projectId))
    .orderBy(
      asc(circuits.circuitListId),
      asc(circuits.sortOrder),
      asc(circuits.id)
    )
    .all();
  const deviceRowRows = database
    .select({
      id: circuitDeviceRows.id,
      circuitId: circuitDeviceRows.circuitId,
      linkedProjectDeviceId: circuitDeviceRows.linkedProjectDeviceId,
      legacyConsumerId: circuitDeviceRows.legacyConsumerId,
      sortOrder: circuitDeviceRows.sortOrder,
      name: circuitDeviceRows.name,
      displayName: circuitDeviceRows.displayName,
      phaseType: circuitDeviceRows.phaseType,
      connectionKind: circuitDeviceRows.connectionKind,
      costGroup: circuitDeviceRows.costGroup,
      category: circuitDeviceRows.category,
      level: circuitDeviceRows.level,
      roomId: circuitDeviceRows.roomId,
      roomNumberSnapshot: circuitDeviceRows.roomNumberSnapshot,
      roomNameSnapshot: circuitDeviceRows.roomNameSnapshot,
      quantity: circuitDeviceRows.quantity,
      powerPerUnit: circuitDeviceRows.powerPerUnit,
      simultaneityFactor: circuitDeviceRows.simultaneityFactor,
      cosPhi: circuitDeviceRows.cosPhi,
      remark: circuitDeviceRows.remark,
      overriddenFields: circuitDeviceRows.overriddenFields,
    })
    .from(circuitDeviceRows)
    .innerJoin(circuits, eq(circuits.id, circuitDeviceRows.circuitId))
    .innerJoin(circuitLists, eq(circuitLists.id, circuits.circuitListId))
    .where(eq(circuitLists.projectId, projectId))
    .orderBy(
      asc(circuitDeviceRows.circuitId),
      asc(circuitDeviceRows.sortOrder),
      asc(circuitDeviceRows.id)
    )
    .all();
  const projectDeviceRows = database
    .select()
    .from(projectDevices)
    .where(eq(projectDevices.projectId, projectId))
    .orderBy(asc(projectDevices.displayName), asc(projectDevices.id))
    .all();
  const floorRows = database
    .select()
    .from(floors)
    .where(eq(floors.projectId, projectId))
    .orderBy(asc(floors.sortOrder), asc(floors.id))
    .all();
  const roomRows = database
    .select()
    .from(rooms)
    .where(eq(rooms.projectId, projectId))
    .orderBy(asc(rooms.roomNumber), asc(rooms.id))
    .all();

  const deviceRowsByCircuit = new Map<string, typeof deviceRowRows>();
  for (const row of deviceRowRows) {
    const entries = deviceRowsByCircuit.get(row.circuitId) ?? [];
    entries.push(row);
    deviceRowsByCircuit.set(row.circuitId, entries);
  }

  const state = parseProjectStateSnapshot({
    schemaVersion: projectStateSnapshotSchemaVersion,
    project: {
      id: project.id,
      name: project.name,
      singlePhaseVoltageV: project.singlePhaseVoltageV,
      threePhaseVoltageV: project.threePhaseVoltageV,
    },
    distributionBoards: boardRows,
    circuitLists: listRows,
    circuitSections: sectionRows,
    circuits: circuitRows.map((circuit) => ({
      ...circuit,
      isReserve: Boolean(circuit.isReserve),
      deviceRows: deviceRowsByCircuit.get(circuit.id) ?? [],
    })),
    projectDevices: projectDeviceRows,
    floors: floorRows,
    rooms: roomRows,
  });
  const payloadJson = serializeProjectStateSnapshot(state);
  return {
    currentRevision: project.currentRevision,
    state,
    payloadJson,
    payloadSha256: hashProjectStatePayload(payloadJson),
  };
}

export function hashProjectStatePayload(payloadJson: string) {
  return crypto.createHash("sha256").update(payloadJson).digest("hex");
}