/**
 * A derived port list can lose a key without anything touching the edges: a state deleted in a
 * machine, the `machine` edge cut, a terminal node or a whole asset removed. Such an edge draws as
 * nothing yet survives every save. `drawnDef` brings the key back as a ghost port so the canvas can
 * draw the edge and offer its right-click menu; `ghostProblem` marks the node. `resolveDef` stays
 * the truth – the interpreter, the compilers and ConnectCommand read it, and it never sees a ghost.
 */
import { describe, expect, it } from 'vitest';
import { CreateAssetCommand, DeleteAssetCommand } from '../../src/core/commands/assetCommands';
import {
  AddNodeCommand,
  ConnectCommand,
  RemoveNodeCommand,
  SetNodeParamCommand,
} from '../../src/core/commands/graphCommands';
import { AddPortCommand } from '../../src/core/commands/portCommands';
import { CommandError } from '../../src/core/commands/Command';
import {
  BEHAVIOR_END,
  BEHAVIOR_PARAM,
  BEHAVIOR_START,
  drawnDef,
  ghostProblem,
  MACHINE_PORT,
  resolveDef,
  RUN_BEHAVIOR,
  STATE,
  STATE_NAME_PARAM,
} from '../../src/core/graph';
import type { BehaviorAsset } from '../../src/core/model/Asset';
import { graphLookup } from '../../src/core/model/graphLookup';
import { graphEditor, makeBehavior, makeProject, type ProjectFixture } from '../helpers';

/** A machine "Doors" with the states Open and Closed, added the way the tab does it. */
function makeMachine(fixture: ProjectFixture, names = ['Open', 'Closed']) {
  const create = new CreateAssetCommand('statemachine', 'Doors');
  fixture.stack.execute(create);
  const ids = names.map((name) => {
    const add = new AddNodeCommand(create.asset.id, STATE, 0, 0, { [STATE_NAME_PARAM]: name });
    fixture.stack.execute(add);
    return add.node.id;
  });
  return { id: create.asset.id, ids };
}

function setup() {
  const f = makeProject();
  const behavior = makeBehavior(f, 'B');
  const edit = graphEditor(f, behavior);
  const seen = (asset: BehaviorAsset, id: string) => {
    const node = asset.graph.nodes.find((n) => n.id === id)!;
    const real = resolveDef(node, asset.graph, graphLookup(f.project))!;
    return {
      real,
      drawn: drawnDef(node, asset.graph, real),
      problem: ghostProblem(node, asset.graph, real),
    };
  };
  const ghosts = (asset: BehaviorAsset, id: string, side: 'inputs' | 'outputs') =>
    seen(asset, id)
      .drawn[side].filter((p) => p.ghost)
      .map((p) => p.key);
  return { f, behavior, edit, seen, ghosts };
}

describe('an edge on a port that is gone', () => {
  it('is no ghost while every edge names a port that exists', () => {
    const { f, behavior, edit, seen, ghosts } = setup();
    const machine = makeMachine(f);
    const start = edit.addNode('OnStart');
    const set = edit.addNode('SetState', { [MACHINE_PORT]: machine.id });
    edit.connect(start, 'exec', set, machine.ids[0]!);
    expect(ghosts(behavior, set.id, 'inputs')).toEqual([]);
    expect(seen(behavior, set.id).problem).toBeNull();
  });

  it('comes back as a ghost when the state it names is deleted in the machine', () => {
    const { f, behavior, edit, seen, ghosts } = setup();
    const machine = makeMachine(f);
    const start = edit.addNode('OnStart');
    const set = edit.addNode('SetState', { [MACHINE_PORT]: machine.id });
    edit.connect(start, 'exec', set, machine.ids[0]!);
    // Deleting the state reaches only the machine's own graph – the behavior's edge stays behind.
    f.stack.execute(new RemoveNodeCommand(machine.id, machine.ids[0]!));
    expect(behavior.graph.edges).toHaveLength(1);
    expect(ghosts(behavior, set.id, 'inputs')).toEqual([machine.ids[0]!]);
    expect(seen(behavior, set.id).problem).toBe('1 edge on a port that is gone');
    f.stack.undo();
    expect(ghosts(behavior, set.id, 'inputs')).toEqual([]);
  });

  it('appears once per state when the State machine literal feeding the input is deleted', () => {
    const { f, behavior, edit, seen, ghosts } = setup();
    const machine = makeMachine(f);
    const literal = edit.addNode('StateMachine', { value: machine.id });
    const branch = edit.addNode('StateBranch');
    edit.connect(literal, 'value', branch, MACHINE_PORT);
    const log = edit.addNode('Log', { message: 'x' });
    const other = edit.addNode('Log', { message: 'y' });
    edit.connect(branch, machine.ids[0]!, log, 'exec');
    edit.connect(branch, machine.ids[1]!, other, 'exec');
    // The literal takes its own edge with it; the two exec edges out of the branch it cannot see.
    f.stack.execute(new RemoveNodeCommand(behavior.id, literal.id));
    expect(ghosts(behavior, branch.id, 'outputs')).toEqual(machine.ids);
    expect(seen(behavior, branch.id).problem).toBe('2 edges on ports that are gone');
  });

  it('appears on every caller when a behavior loses its start node', () => {
    const f = makeProject();
    const callee = makeBehavior(f, 'Double');
    const calleeEdit = graphEditor(f, callee);
    const start = calleeEdit.addNode(BEHAVIOR_START);
    const end = calleeEdit.addNode(BEHAVIOR_END);
    f.stack.execute(new AddPortCommand(callee.id, start.id, { key: 'in1', kind: 'number' }));
    f.stack.execute(new AddPortCommand(callee.id, end.id, { key: 'out1', kind: 'number' }));
    const caller = makeBehavior(f, 'Caller');
    const edit = graphEditor(f, caller);
    const call = edit.addNode(RUN_BEHAVIOR, { [BEHAVIOR_PARAM]: callee.id });
    const number = edit.addNode('Number', { value: 3 });
    edit.connect(number, 'value', call, 'in1');
    const node = () => caller.graph.nodes.find((n) => n.id === call.id)!;
    const real = () => resolveDef(node(), caller.graph, graphLookup(f.project))!;
    expect(drawnDef(node(), caller.graph, real()).inputs.filter((p) => p.ghost)).toHaveLength(0);
    f.stack.execute(new RemoveNodeCommand(callee.id, start.id));
    expect(
      drawnDef(node(), caller.graph, real())
        .inputs.filter((p) => p.ghost)
        .map((p) => p.key),
    ).toEqual(['in1']);
  });

  it('appears when the machine asset itself is deleted', () => {
    const { f, behavior, edit, ghosts } = setup();
    const machine = makeMachine(f);
    const start = edit.addNode('OnStart');
    const set = edit.addNode('SetState', { [MACHINE_PORT]: machine.id });
    edit.connect(start, 'exec', set, machine.ids[0]!);
    f.stack.execute(new DeleteAssetCommand(machine.id));
    expect(ghosts(behavior, set.id, 'inputs')).toEqual([machine.ids[0]!]);
  });

  it('goes last, so no real port row moves because of it', () => {
    const { f, behavior, edit, seen } = setup();
    const machine = makeMachine(f);
    const start = edit.addNode('OnStart');
    const set = edit.addNode('SetState', { [MACHINE_PORT]: machine.id });
    edit.connect(start, 'exec', set, machine.ids[0]!);
    f.stack.execute(new RemoveNodeCommand(machine.id, machine.ids[0]!));
    const { real, drawn } = seen(behavior, set.id);
    const keys = drawn.inputs.map((p) => p.key);
    expect(keys.slice(0, real.inputs.length)).toEqual(real.inputs.map((p) => p.key));
    expect(keys.at(-1)).toBe(machine.ids[0]!);
  });

  it('is a handle only: resolveDef has no ghost, so nothing can be connected to one', () => {
    const { f, behavior, edit, seen } = setup();
    const machine = makeMachine(f);
    const start = edit.addNode('OnStart');
    const set = edit.addNode('SetState', { [MACHINE_PORT]: machine.id });
    edit.connect(start, 'exec', set, machine.ids[0]!);
    f.stack.execute(new RemoveNodeCommand(machine.id, machine.ids[0]!));
    const { real } = seen(behavior, set.id);
    expect(real.inputs.some((p) => p.key === machine.ids[0]!)).toBe(false);
    const second = edit.addNode('OnUpdate');
    expect(() =>
      f.stack.execute(
        new ConnectCommand(
          behavior.id,
          { node: second.id, port: 'exec' },
          { node: set.id, port: machine.ids[0]! },
        ),
      ),
    ).toThrow(CommandError);
  });

  it('survives a param change that orphans the edge, until that command takes it', () => {
    const { f, behavior, edit, seen, ghosts } = setup();
    const machine = makeMachine(f);
    const start = edit.addNode('OnStart');
    const set = edit.addNode('SetState', { [MACHINE_PORT]: machine.id });
    edit.connect(start, 'exec', set, machine.ids[0]!);
    // SetNodeParamCommand is the one path that already cleans up: no edge left, so no ghost.
    f.stack.execute(new SetNodeParamCommand(behavior.id, set.id, MACHINE_PORT, ''));
    expect(behavior.graph.edges).toHaveLength(0);
    expect(ghosts(behavior, set.id, 'inputs')).toEqual([]);
    f.stack.undo();
    expect(seen(behavior, set.id).problem).toBeNull();
  });
});