import path from "node:path";
import assert from "node:assert/strict";
import { describe, it } from "node:test";
import { eq } from "drizzle-orm";
import { migrate } from "drizzle-orm/better-sqlite3/migrator";
import {
  createDatabaseContext,
  type DatabaseContext,
} from "../src/db/database-context.js";
import { ProjectHistoryRepository } from "../src/db/repositories/project-history.repository.js";
import { ProjectLocationStructureProjectCommandRepository } from "../src/db/repositories/project-location-structure-project-command.repository.js";
import { buildings } from "../src/db/schema/buildings.js";
import { floors } from "../src/db/schema/floors.js";
import { projects } from "../src/db/schema/projects.js";
import {
  assertProjectFloorInsertProjectCommand,
  createProjectBuildingDeleteProjectCommand,
  createProjectBuildingInsertProjectCommand,
  createProjectBuildingSnapshot,
  createProjectBuildingUpdateProjectCommand,
  createProjectFloorInsertProjectCommand,
  createProjectFloorSnapshot,
  createProjectFloorUpdateProjectCommand,
  projectFloorCommandSchemaVersion,
  type ProjectLocationStructureProjectCommand,
} from "../src/domain/models/project-location-structure-project-command.model.js";
import {
  createBuildingSchema,
  createFloorSchema,
  updateFloorSchema,
} from "../src/shared/validation/project-structure.schemas.js";

function createTestDatabase(): DatabaseContext {
  const context = createDatabaseContext(":memory:");
  migrate(context.db, {
    migrationsFolder: path.resolve("src", "db", "migrations"),
  });
  context.db
    .insert(projects)
    .values([
      { id: "project-1", name: "Test project" },
      { id: "project-2", name: "Foreign project" },
    ])
    .run();
  return context;
}

/** Executes a user command and returns a runner for its undo and redo. */
function createRunner(context: DatabaseContext) {
  const repository = new ProjectLocationStructureProjectCommandRepository(
    context.db
  );
  const history = new ProjectHistoryRepository(context.db);
  let revision = 0;
  const run = (
    command: ProjectLocationStructureProjectCommand,
    source: "user" | "undo" | "redo" = "user"
  ) => {
    const step =
      source === "user" ? null : history.getNextCommand("project-1", source);
    if (source !== "user") {
      assert.ok(step);
    }
    const result = repository.execute({
      projectId: "project-1",
      expectedRevision: revision,
      source,
      historyTargetChangeSetId: step?.changeSetId,
      command,
    });
    revision += 1;
    return result;
  };
  return { repository, run };
}

function getBuilding(context: DatabaseContext, id: string) {
  return context.db.select().from(buildings).where(eq(buildings.id, id)).get();
}

function getFloor(context: DatabaseContext, id: string) {
  return context.db.select().from(floors).where(eq(floors.id, id)).get();
}

describe("project building structure", () => {
  it("creates, renames and deletes buildings with persisted undo and redo", () => {
    const context = createTestDatabase();
    try {
      const { run } = createRunner(context);
      const building = createProjectBuildingSnapshot("project-1", " Haus A ", 0);
      assert.equal(building.name, "Haus A");

      const insert = createProjectBuildingInsertProjectCommand(building);
      const inserted = run(insert);
      assert.deepEqual(getBuilding(context, building.id), building);

      const renamed = { ...building, name: "Haus B" };
      const update = createProjectBuildingUpdateProjectCommand(building, renamed);
      const updated = run(update);
      assert.equal(getBuilding(context, building.id)?.name, "Haus B");

      run(updated.inverse, "undo");
      assert.deepEqual(getBuilding(context, building.id), building);
      run(inserted.inverse, "undo");
      assert.equal(getBuilding(context, building.id), undefined);
      run(insert, "redo");
      run(update, "redo");
      assert.deepEqual(getBuilding(context, building.id), renamed);

      const deleted = run(createProjectBuildingDeleteProjectCommand(renamed));
      assert.equal(getBuilding(context, building.id), undefined);
      run(deleted.inverse, "undo");
      assert.deepEqual(getBuilding(context, building.id), renamed);
    } finally {
      context.close();
    }
  });

  it("assigns floors to buildings and blocks deleting a building in use", () => {
    const context = createTestDatabase();
    try {
      const { run } = createRunner(context);
      const houseA = createProjectBuildingSnapshot("project-1", "Haus A", 0);
      const houseB = createProjectBuildingSnapshot("project-1", "Haus B", 1);
      run(createProjectBuildingInsertProjectCommand(houseA));
      run(createProjectBuildingInsertProjectCommand(houseB));

      const floor = createProjectFloorSnapshot("project-1", "EG", 0, houseA.id);
      const floorInsert = createProjectFloorInsertProjectCommand(floor);
      assert.equal(floorInsert.schemaVersion, projectFloorCommandSchemaVersion);
      run(floorInsert);
      assert.deepEqual(getFloor(context, floor.id), floor);

      const moved = { ...floor, buildingId: houseB.id };
      const moveCommand = createProjectFloorUpdateProjectCommand(floor, moved);
      const movedResult = run(moveCommand);
      assert.equal(getFloor(context, floor.id)?.buildingId, houseB.id);

      assert.throws(
        () => run(createProjectBuildingDeleteProjectCommand(houseB)),
        /solange Etagen zugeordnet/
      );
      assert.ok(getBuilding(context, houseB.id));

      run(movedResult.inverse, "undo");
      assert.equal(getFloor(context, floor.id)?.buildingId, houseA.id);
      run(moveCommand, "redo");
      assert.equal(getFloor(context, floor.id)?.buildingId, houseB.id);

      const unassigned = { ...moved, buildingId: null };
      run(createProjectFloorUpdateProjectCommand(moved, unassigned));
      assert.equal(getFloor(context, floor.id)?.buildingId, null);
      run(createProjectBuildingDeleteProjectCommand(houseB));
      assert.equal(getBuilding(context, houseB.id), undefined);
    } finally {
      context.close();
    }
  });

  it("rejects floors that reference a missing or foreign building", () => {
    const context = createTestDatabase();
    try {
      const { run } = createRunner(context);
      context.db
        .insert(buildings)
        .values({ id: "foreign", projectId: "project-2", name: "Fremd", sortOrder: 0 })
        .run();
      assert.throws(
        () =>
          run(
            createProjectFloorInsertProjectCommand(
              createProjectFloorSnapshot("project-1", "EG", 0, "foreign")
            )
          ),
        /foreign building/
      );
      assert.throws(
        () =>
          run(
            createProjectFloorInsertProjectCommand(
              createProjectFloorSnapshot("project-1", "EG", 0, "missing")
            )
          ),
        /foreign building/
      );
      assert.equal(context.db.select().from(floors).all().length, 0);

      const floor = createProjectFloorSnapshot("project-1", "EG", 0);
      run(createProjectFloorInsertProjectCommand(floor));
      assert.throws(
        () =>
          run(
            createProjectFloorUpdateProjectCommand(floor, {
              ...floor,
              buildingId: "foreign",
            })
          ),
        /foreign building/
      );
      assert.throws(
        () => createProjectFloorUpdateProjectCommand(floor, { ...floor }),
        /only the name or the building/
      );
      assert.throws(
        () =>
          createProjectFloorUpdateProjectCommand(floor, {
            ...floor,
            sortOrder: 5,
            name: "Erdgeschoss",
          }),
        /only the name or the building/
      );
    } finally {
      context.close();
    }
  });

  it("executes version 1 floor commands recorded before buildings existed", () => {
    const context = createTestDatabase();
    try {
      const { run } = createRunner(context);
      const legacyFloor = {
        id: "floor-legacy",
        projectId: "project-1",
        name: "EG",
        sortOrder: 0,
      };
      const legacyInsert = {
        schemaVersion: 1 as const,
        type: "project-floor.insert" as const,
        payload: { floor: legacyFloor },
      };
      assertProjectFloorInsertProjectCommand(legacyInsert);
      const inserted = run(legacyInsert);
      assert.deepEqual(getFloor(context, legacyFloor.id), {
        ...legacyFloor,
        buildingId: null,
      });
      // The inverse is always written in the current version.
      assert.equal(inserted.inverse.schemaVersion, projectFloorCommandSchemaVersion);

      const legacyUpdate = {
        schemaVersion: 1 as const,
        type: "project-floor.update" as const,
        payload: {
          expected: legacyFloor,
          target: { ...legacyFloor, name: "Erdgeschoss" },
        },
      };
      const updated = run(legacyUpdate);
      assert.equal(getFloor(context, legacyFloor.id)?.name, "Erdgeschoss");
      run(updated.inverse, "undo");
      assert.equal(getFloor(context, legacyFloor.id)?.name, "EG");

      // A version 1 snapshot must not carry buildingId, a version 2 one must.
      assert.throws(() =>
        assertProjectFloorInsertProjectCommand({
          schemaVersion: 1,
          type: "project-floor.insert",
          payload: { floor: { ...legacyFloor, buildingId: null } },
        })
      );
      assert.throws(() =>
        assertProjectFloorInsertProjectCommand({
          schemaVersion: 2,
          type: "project-floor.insert",
          payload: { floor: legacyFloor },
        })
      );
    } finally {
      context.close();
    }
  });

  it("validates building and floor requests", () => {
    assert.equal(
      createBuildingSchema.safeParse({ expectedRevision: 0, name: "Haus A" }).success,
      true
    );
    assert.equal(
      createBuildingSchema.safeParse({ expectedRevision: 0, name: " " }).success,
      false
    );
    assert.equal(
      createBuildingSchema.safeParse({
        expectedRevision: 0,
        name: "Haus A",
        sortOrder: 1,
      }).success,
      false
    );
    for (const buildingId of [undefined, null, "building-1"]) {
      assert.equal(
        createFloorSchema.safeParse({ expectedRevision: 0, name: "EG", buildingId })
          .success,
        true
      );
    }
    assert.equal(
      updateFloorSchema.safeParse({ expectedRevision: 0, name: "EG", buildingId: "" })
        .success,
      false
    );
  });
});