import { describe, expect, it } from 'vitest';
import { RenameVariableCommand } from '../../src/core/commands/variableCommands';
import { GraphInterpreter, resolveDef } from '../../src/core/graph';
import type { BehaviorAsset } from '../../src/core/model/Asset';
import { behaviorLookup } from '../../src/core/model/behaviorPrograms';
import { fakeContext, graphEditor, makeBehavior, makeProject } from '../helpers';

function setup() {
  const fixture = makeProject();
  const behavior = makeBehavior(fixture, 'B', ['count', 'copy']);
  return { fixture, behavior, edit: graphEditor(fixture, behavior) };
}

function run(behavior: BehaviorAsset, fixture: ReturnType<typeof makeProject>, count = 5) {
  const ctx = fakeContext({ variables: { count, copy: 0 } });
  new GraphInterpreter(behavior.graph, behaviorLookup(fixture.project)).fire('OnStart', ctx);
  return ctx.variables;
}

const titleOf = (behavior: BehaviorAsset, index: number) =>
  resolveDef(behavior.graph.nodes[index]!, behavior.graph, () => null)!.label;

describe('the Variable node', () => {
  it('can be read without a flow ever reaching it', () => {
    const { fixture, behavior, edit } = setup();
    const start = edit.addNode('OnStart');
    const variable = edit.addNode('Variable', { variable: 'count' });
    const copy = edit.addNode('SetVariable', { variable: 'copy' });
    edit.wire([
      [start, 'exec', copy, 'exec'],
      [variable, 'value', copy, 'value'],
    ]);
    expect(run(behavior, fixture)).toEqual({ count: 5, copy: 5 });
  });

  it('writes its input when the flow arrives, unconnected as well as through an edge', () => {
    const { fixture, behavior, edit } = setup();
    const start = edit.addNode('OnStart');
    const inline = edit.addNode('Variable', { variable: 'count', value: 7 });
    const number = edit.addNode('Number', { value: 3 });
    const wired = edit.addNode('Variable', { variable: 'copy' });
    edit.wire([
      [start, 'exec', inline, 'exec'],
      [inline, 'exec', wired, 'exec'],
      [number, 'value', wired, 'value'],
    ]);
    expect(run(behavior, fixture)).toEqual({ count: 7, copy: 3 });
  });

  it('counts up through its own output: count = count + 1', () => {
    const { fixture, behavior, edit } = setup();
    const start = edit.addNode('OnStart');
    const variable = edit.addNode('Variable', { variable: 'count' });
    const add = edit.addNode('Add', { b: 1 });
    edit.wire([
      [start, 'exec', variable, 'exec'],
      [variable, 'value', add, 'a'],
      [add, 'result', variable, 'value'],
    ]);
    expect(run(behavior, fixture).count).toBe(6);
  });

  it('is read at the moment it is asked, so it sees a later write by another node', () => {
    const { fixture, behavior, edit } = setup();
    const start = edit.addNode('OnStart');
    const variable = edit.addNode('Variable', { variable: 'count', value: 7 });
    const overwrite = edit.addNode('SetVariable', { variable: 'count', value: 9 });
    const copy = edit.addNode('SetVariable', { variable: 'copy' });
    edit.wire([
      [start, 'exec', variable, 'exec'],
      [variable, 'exec', overwrite, 'exec'],
      [overwrite, 'exec', copy, 'exec'],
      [variable, 'value', copy, 'value'],
    ]);
    expect(run(behavior, fixture)).toEqual({ count: 9, copy: 9 });
  });
});

describe('variable node titles', () => {
  it('name the picked variable, and keep the plain title until one is picked', () => {
    const { behavior, edit } = setup();
    edit.addNode('GetVariable', { variable: 'count' });
    edit.addNode('SetVariable', { variable: 'count' });
    edit.addNode('Variable', { variable: 'count' });
    edit.addNode('GetVariable');
    edit.addNode('Variable');
    expect([0, 1, 2, 3, 4].map((i) => titleOf(behavior, i))).toEqual([
      'Get count',
      'Set count',
      'count',
      'Get variable',
      'Variable',
    ]);
  });

  it('follow a renamed variable', () => {
    const { fixture, behavior, edit } = setup();
    edit.addNode('Variable', { variable: 'count' });
    fixture.stack.execute(new RenameVariableCommand(behavior.id, 'count', 'score'));
    expect(titleOf(behavior, 0)).toBe('score');
  });
});