from typing import Optional
from unittest.mock import Mock

import pytest

from invokeai.app.invocations.baseinvocation import BaseInvocation, BaseInvocationOutput, InvocationContext
from invokeai.app.invocations.collections import RangeInvocation
from invokeai.app.invocations.math import AddInvocation, MultiplyInvocation
from invokeai.app.services.shared.graph import (
    CollectInvocation,
    Graph,
    GraphExecutionState,
    IterateInvocation,
)

# This import must happen before other invoke imports or test in other files(!!) break
from tests.test_nodes import (
    PromptCollectionTestInvocation,
    PromptTestInvocation,
    TextToImageTestInvocation,
    create_edge,
)


@pytest.fixture
def simple_graph() -> Graph:
    g = Graph()
    g.add_node(PromptTestInvocation(id="1", prompt="Banana sushi"))
    g.add_node(TextToImageTestInvocation(id="2"))
    g.add_edge(create_edge("1", "prompt", "2", "prompt"))
    return g


def invoke_next(g: GraphExecutionState) -> tuple[Optional[BaseInvocation], Optional[BaseInvocationOutput]]:
    n = g.next()
    if n is None:
        return (None, None)

    print(f"invoking {n.id}: {type(n)}")
    o = n.invoke(Mock(InvocationContext))
    g.complete(n.id, o)

    return (n, o)


def test_graph_state_executes_in_order(simple_graph: Graph):
    g = GraphExecutionState(graph=simple_graph)

    n1 = invoke_next(g)
    n2 = invoke_next(g)
    n3 = g.next()

    assert g.prepared_source_mapping[n1[0].id] == "1"
    assert g.prepared_source_mapping[n2[0].id] == "2"
    assert n3 is None
    assert g.results[n1[0].id].prompt == n1[0].prompt
    assert n2[0].prompt == n1[0].prompt


def test_graph_is_complete(simple_graph: Graph):
    g = GraphExecutionState(graph=simple_graph)
    _ = invoke_next(g)
    _ = invoke_next(g)
    _ = g.next()

    assert g.is_complete()


def test_graph_is_not_complete(simple_graph: Graph):
    g = GraphExecutionState(graph=simple_graph)
    _ = invoke_next(g)
    _ = g.next()

    assert not g.is_complete()


# TODO: test completion with iterators/subgraphs


def test_graph_state_expands_iterator():
    graph = Graph()
    graph.add_node(RangeInvocation(id="0", start=0, stop=3, step=1))
    graph.add_node(IterateInvocation(id="1"))
    graph.add_node(MultiplyInvocation(id="2", b=10))
    graph.add_node(AddInvocation(id="3", b=1))
    graph.add_edge(create_edge("0", "collection", "1", "collection"))
    graph.add_edge(create_edge("1", "item", "2", "a"))
    graph.add_edge(create_edge("2", "value", "3", "a"))

    g = GraphExecutionState(graph=graph)
    while not g.is_complete():
        invoke_next(g)

    prepared_add_nodes = g.source_prepared_mapping["3"]
    results = {g.results[n].value for n in prepared_add_nodes}
    expected = {1, 11, 21}
    assert results == expected


def test_graph_state_collects():
    graph = Graph()
    test_prompts = ["Banana sushi", "Cat sushi"]
    graph.add_node(PromptCollectionTestInvocation(id="1", collection=list(test_prompts)))
    graph.add_node(IterateInvocation(id="2"))
    graph.add_node(PromptTestInvocation(id="3"))
    graph.add_node(CollectInvocation(id="4"))
    graph.add_edge(create_edge("1", "collection", "2", "collection"))
    graph.add_edge(create_edge("2", "item", "3", "prompt"))
    graph.add_edge(create_edge("3", "prompt", "4", "item"))

    g = GraphExecutionState(graph=graph)
    _ = invoke_next(g)
    _ = invoke_next(g)
    _ = invoke_next(g)
    _ = invoke_next(g)
    _ = invoke_next(g)
    n6 = invoke_next(g)

    assert isinstance(n6[0], CollectInvocation)

    assert sorted(g.results[n6[0].id].collection) == sorted(test_prompts)


def test_graph_state_prepares_eagerly():
    """Tests that all prepareable nodes are prepared"""
    graph = Graph()

    test_prompts = ["Banana sushi", "Cat sushi"]
    graph.add_node(PromptCollectionTestInvocation(id="prompt_collection", collection=list(test_prompts)))
    graph.add_node(IterateInvocation(id="iterate"))
    graph.add_node(PromptTestInvocation(id="prompt_iterated"))
    graph.add_edge(create_edge("prompt_collection", "collection", "iterate", "collection"))
    graph.add_edge(create_edge("iterate", "item", "prompt_iterated", "prompt"))

    # separated, fully-preparable chain of nodes
    graph.add_node(PromptTestInvocation(id="prompt_chain_1", prompt="Dinosaur sushi"))
    graph.add_node(PromptTestInvocation(id="prompt_chain_2"))
    graph.add_node(PromptTestInvocation(id="prompt_chain_3"))
    graph.add_edge(create_edge("prompt_chain_1", "prompt", "prompt_chain_2", "prompt"))
    graph.add_edge(create_edge("prompt_chain_2", "prompt", "prompt_chain_3", "prompt"))

    g = GraphExecutionState(graph=graph)
    g.next()

    assert "prompt_collection" in g.source_prepared_mapping
    assert "prompt_chain_1" in g.source_prepared_mapping
    assert "prompt_chain_2" in g.source_prepared_mapping
    assert "prompt_chain_3" in g.source_prepared_mapping
    assert "iterate" not in g.source_prepared_mapping
    assert "prompt_iterated" not in g.source_prepared_mapping


def test_graph_executes_depth_first():
    """Tests that the graph executes depth-first, executing a branch as far as possible before moving to the next branch"""
    graph = Graph()

    test_prompts = ["Banana sushi", "Cat sushi"]
    graph.add_node(PromptCollectionTestInvocation(id="prompt_collection", collection=list(test_prompts)))
    graph.add_node(IterateInvocation(id="iterate"))
    graph.add_node(PromptTestInvocation(id="prompt_iterated"))
    graph.add_node(PromptTestInvocation(id="prompt_successor"))
    graph.add_edge(create_edge("prompt_collection", "collection", "iterate", "collection"))
    graph.add_edge(create_edge("iterate", "item", "prompt_iterated", "prompt"))
    graph.add_edge(create_edge("prompt_iterated", "prompt", "prompt_successor", "prompt"))

    g = GraphExecutionState(graph=graph)
    _ = invoke_next(g)
    _ = invoke_next(g)
    _ = invoke_next(g)
    _ = invoke_next(g)

    # Because ordering is not guaranteed, we cannot compare results directly.
    # Instead, we must count the number of results.
    def get_completed_count(g: GraphExecutionState, id: str):
        ids = list(g.source_prepared_mapping[id])
        completed_ids = [i for i in g.executed if i in ids]
        return len(completed_ids)

    # Check at each step that the number of executed nodes matches the expectation for depth-first execution
    assert get_completed_count(g, "prompt_iterated") == 1
    assert get_completed_count(g, "prompt_successor") == 0

    _ = invoke_next(g)

    assert get_completed_count(g, "prompt_iterated") == 1
    assert get_completed_count(g, "prompt_successor") == 1

    _ = invoke_next(g)

    assert get_completed_count(g, "prompt_iterated") == 2
    assert get_completed_count(g, "prompt_successor") == 1

    _ = invoke_next(g)

    assert get_completed_count(g, "prompt_iterated") == 2
    assert get_completed_count(g, "prompt_successor") == 2


# Because this tests deterministic ordering, we run it multiple times
@pytest.mark.parametrize("execution_number", range(5))
def test_graph_iterate_execution_order(execution_number: int):
    """Tests that iterate nodes execution is ordered by the order of the collection"""

    graph = Graph()

    test_prompts = ["Banana sushi", "Cat sushi", "Strawberry Sushi", "Dinosaur Sushi"]
    graph.add_node(PromptCollectionTestInvocation(id="prompt_collection", collection=list(test_prompts)))
    graph.add_node(IterateInvocation(id="iterate"))
    graph.add_node(PromptTestInvocation(id="prompt_iterated"))
    graph.add_edge(create_edge("prompt_collection", "collection", "iterate", "collection"))
    graph.add_edge(create_edge("iterate", "item", "prompt_iterated", "prompt"))

    g = GraphExecutionState(graph=graph)
    _ = invoke_next(g)
    _ = invoke_next(g)
    assert _[1].item == "Banana sushi"
    _ = invoke_next(g)
    assert _[1].item == "Cat sushi"
    _ = invoke_next(g)
    assert _[1].item == "Strawberry Sushi"
    _ = invoke_next(g)
    assert _[1].item == "Dinosaur Sushi"
    _ = invoke_next(g)