import { describe, expect, it } from "vitest";

import { edgeVisuals, PATH_PALETTE } from "@/components/admin/tech-tree/edgeVisuals";
import { applyPins, pinsToFreeze } from "@/components/admin/tech-tree/freeze";
import { computeLayout } from "@/components/admin/tech-tree/layout";
import { COLUMN_STEP, type TreeTech } from "@/components/admin/tech-tree/types";

const tech = (over: Partial<TreeTech> & { id: number }): TreeTech => ({
  name: `Tech ${String(over.id).padStart(2, "0")}`,
  type: "upgrade",
  approvalStatus: "in_progress",
  summary: "",
  categoryId: null,
  prereqAnd: [],
  prereqOr: [],
  resourceCosts: [],
  treePosition: null,
  ...over,
});

const positionsOf = (techs: TreeTech[]) =>
  new Map(computeLayout(techs, []).nodes.map((n) => [n.techId, { x: n.x, y: n.y }]));

describe("tech tree stability (freeze on data change)", () => {
  it("pins every card the new layout would move, including the target's dependents", () => {
    // B (2) already has a dependent C (3). Linking A (1) -> B relocates B,
    // and C follows B in the ordered layout: both must be pinned in place.
    const before = [
      tech({ id: 1 }),
      tech({ id: 2 }),
      tech({ id: 3, prereqAnd: [2] }),
      tech({ id: 4 }),
    ];
    const current = positionsOf(before);
    const after = before.map((t) => (t.id === 2 ? { ...t, prereqAnd: [1] } : t));

    const pins = pinsToFreeze(current, after, []);
    expect(pins.has(2)).toBe(true);
    expect(pins.has(3)).toBe(true);

    // With the pins applied, NOTHING on screen moves.
    const frozen = positionsOf(applyPins(after, pins));
    for (const [id, pos] of current) {
      expect(frozen.get(id)).toEqual(pos);
    }
  });

  it("does not pin cards whose position is unchanged", () => {
    const before = [tech({ id: 1 }), tech({ id: 2 }), tech({ id: 3 })];
    const current = positionsOf(before);
    const pins = pinsToFreeze(current, before, []);
    expect(pins.size).toBe(0);
  });

  it("skips technologies that have no on-screen position yet (just created)", () => {
    const before = [tech({ id: 1 }), tech({ id: 3 })];
    const current = positionsOf(before);
    // A new tech whose name sorts between the others would shift catalog ranks.
    const after = [...before, tech({ id: 2 })];
    const pins = pinsToFreeze(current, after, []);
    expect(pins.has(2)).toBe(false);
    const frozen = positionsOf(applyPins(after, pins));
    expect(frozen.get(1)).toEqual(current.get(1));
    expect(frozen.get(3)).toEqual(current.get(3));
  });
});

describe("tech tree edge visuals (path colors + lanes)", () => {
  it("colors separate progression paths differently and keeps one color per chain", () => {
    const techs = [
      tech({ id: 1 }),
      tech({ id: 2, prereqAnd: [1] }),
      tech({ id: 3, prereqAnd: [2] }),
      tech({ id: 10 }),
      tech({ id: 11, prereqAnd: [10] }),
    ];
    const edges = [
      { id: "a", source: 1, target: 2 },
      { id: "b", source: 2, target: 3 },
      { id: "c", source: 10, target: 11 },
    ];
    const visuals = edgeVisuals(techs, edges, positionsOf(techs), COLUMN_STEP);
    expect(visuals.get("a")!.color).toBe(visuals.get("b")!.color);
    expect(visuals.get("a")!.color).not.toBe(visuals.get("c")!.color);
    expect(PATH_PALETTE).toContain(visuals.get("c")!.color);
  });

  it("gives different sources crossing the same gap their own lanes", () => {
    const techs = [
      tech({ id: 1 }),
      tech({ id: 2 }),
      tech({ id: 3, prereqAnd: [1] }),
      tech({ id: 4, prereqAnd: [2] }),
    ];
    const edges = [
      { id: "a", source: 1, target: 3 },
      { id: "b", source: 2, target: 4 },
    ];
    const visuals = edgeVisuals(techs, edges, positionsOf(techs), COLUMN_STEP);
    expect(visuals.get("a")!.stepPosition).not.toBe(visuals.get("b")!.stepPosition);
    for (const v of visuals.values()) {
      expect(v.stepPosition).toBeGreaterThanOrEqual(0.2);
      expect(v.stepPosition).toBeLessThanOrEqual(0.8);
    }
  });

  it("keeps edges from the same source in one lane (a fan-out bus)", () => {
    const techs = [
      tech({ id: 1 }),
      tech({ id: 2, prereqAnd: [1] }),
      tech({ id: 3, prereqAnd: [1] }),
    ];
    const edges = [
      { id: "a", source: 1, target: 2 },
      { id: "b", source: 1, target: 3 },
    ];
    const visuals = edgeVisuals(techs, edges, positionsOf(techs), COLUMN_STEP);
    expect(visuals.get("a")!.stepPosition).toBe(0.5);
    expect(visuals.get("b")!.stepPosition).toBe(0.5);
  });
});