import { describe, it, expect } from "vitest";
import { describeActivity } from "@/lib/activity/format";
import type { ActivityRecord } from "@/lib/pb/types";

function row(overrides: Partial<ActivityRecord>): ActivityRecord {
  return {
    id: "a1",
    created: "2026-09-16 10:00:00.000Z",
    project: "p1",
    card: "c1",
    actor: "u1",
    action: "card_updated",
    field: "",
    old_value: "",
    new_value: "",
    ...overrides,
  } as ActivityRecord;
}

describe("describeActivity", () => {
  it("describes a priority change in words, not codes", () => {
    expect(
      describeActivity(
        row({ action: "priority_changed", field: "priority", old_value: "medium", new_value: "high" })
      )
    ).toBe("changed priority from Medium to High");
  });

  it("describes setting a target date that had none", () => {
    expect(
      describeActivity(
        row({ action: "date_changed", field: "target_date", old_value: "", new_value: "2026-10-01" })
      )
    ).toBe("set the target date to 1 Oct 2026");
  });

  it("describes moving a target date", () => {
    expect(
      describeActivity(
        row({
          action: "date_changed",
          field: "target_date",
          old_value: "2026-10-01 00:00:00.000Z",
          new_value: "2026-11-15",
        })
      )
    ).toBe("moved the target date from 1 Oct 2026 to 15 Nov 2026");
  });

  it("describes clearing a target date", () => {
    expect(
      describeActivity(
        row({ action: "date_changed", field: "target_date", old_value: "2026-10-01", new_value: "" })
      )
    ).toBe("cleared the target date");
  });

  it("describes card creation, acceptance and archiving", () => {
    expect(describeActivity(row({ action: "card_created", new_value: "Add a POS system" })))
      .toBe("added this card");
    expect(describeActivity(row({ action: "card_accepted" }))).toBe("accepted this request");
    expect(describeActivity(row({ action: "card_archived" }))).toBe("archived this card");
  });

  it("names the destination when a card moves", () => {
    expect(describeActivity(row({ action: "card_moved", new_value: "In Progress" })))
      .toBe("moved this card to In Progress");
  });

  it("falls back gracefully when a move has no destination recorded", () => {
    expect(describeActivity(row({ action: "card_moved", new_value: "" })))
      .toBe("moved this card");
  });

  it("describes comments and subtasks", () => {
    expect(describeActivity(row({ action: "comment_added" }))).toBe("commented");
    expect(
      describeActivity(row({ action: "subtask_toggled", new_value: "true", field: "Wire up the till" }))
    ).toBe("completed “Wire up the till”");
    expect(
      describeActivity(row({ action: "subtask_toggled", new_value: "false", field: "Wire up the till" }))
    ).toBe("reopened “Wire up the till”");
  });

  it("describes a column move with the new column name", () => {
    expect(
      describeActivity(
        row({ action: "column_changed", field: "column", old_value: "col_done", new_value: "Backlog" })
      )
    ).toBe("moved this card to Backlog");
  });

  it("describes a column move out of a column when only the old name is known", () => {
    expect(
      describeActivity(
        row({ action: "column_changed", field: "column", old_value: "Done", new_value: "" })
      )
    ).toBe("moved this card out of Done");
  });

  it("describes a client proposal in human terms", () => {
    expect(
      describeActivity(
        row({
          action: "date_proposed",
          field: "proposed_target_date",
          old_value: "",
          new_value: "2026-11-15",
        })
      )
    ).toBe("proposed moving this card to 15 Nov 2026");
  });

  it("describes an accepted proposal with its date", () => {
    expect(
      describeActivity(
        row({
          action: "date_proposal_resolved",
          field: "proposed_target_date",
          old_value: "2026-11-15",
          new_value: "accepted",
        })
      )
    ).toBe("accepted the proposal for 15 Nov 2026");
  });

  it("describes a dismissed proposal with its date", () => {
    expect(
      describeActivity(
        row({
          action: "date_proposal_resolved",
          field: "proposed_target_date",
          old_value: "2026-11-15",
          new_value: "dismissed",
        })
      )
    ).toBe("dismissed the proposal for 15 Nov 2026");
  });

  it("falls back gracefully when a resolved proposal has no date", () => {
    expect(
      describeActivity(
        row({
          action: "date_proposal_resolved",
          field: "proposed_target_date",
          old_value: "",
          new_value: "accepted",
        })
      )
    ).toBe("accepted a proposal");
  });

  it("describes a generic update", () => {
    expect(describeActivity(row({ action: "card_updated", field: "description" })))
      .toBe("updated the description");
    expect(describeActivity(row({ action: "card_updated", field: "title" })))
      .toBe("renamed this card");
  });

  it("never returns an empty string for an unknown action", () => {
    // Double assertion on purpose: the point is to simulate an action value
    // added by a later phase that this switch has not learned yet.
    const unknown = "something_new" as unknown as ActivityRecord["action"];
    const result = describeActivity(row({ action: unknown }));
    expect(result.length).toBeGreaterThan(0);
  });
});