# RUN: %PYTHON %s | FileCheck %s

import gc
import io
import itertools
from mlir.ir import *


def run(f):
    print("\nTEST:", f.__name__)
    f()
    gc.collect()
    assert Context._get_live_count() == 0


# CHECK-LABEL: TEST: test_insert_at_block_end
def test_insert_at_block_end():
    ctx = Context()
    ctx.allow_unregistered_dialects = True
    with Location.unknown(ctx):
        module = Module.parse(
            r"""
      func.func @foo() -> () {
        "custom.op1"() : () -> ()
      }
    """
        )
        entry_block = module.body.operations[0].regions[0].blocks[0]
        ip = InsertionPoint(entry_block)
        ip.insert(Operation.create("custom.op2"))
        # CHECK: "custom.op1"
        # CHECK: "custom.op2"
        module.operation.print()


run(test_insert_at_block_end)


# CHECK-LABEL: TEST: test_insert_before_operation
def test_insert_before_operation():
    ctx = Context()
    ctx.allow_unregistered_dialects = True
    with Location.unknown(ctx):
        module = Module.parse(
            r"""
      func.func @foo() -> () {
        "custom.op1"() : () -> ()
        "custom.op2"() : () -> ()
      }
    """
        )
        entry_block = module.body.operations[0].regions[0].blocks[0]
        ip = InsertionPoint(entry_block.operations[1])
        ip.insert(Operation.create("custom.op3"))
        # CHECK: "custom.op1"
        # CHECK: "custom.op3"
        # CHECK: "custom.op2"
        module.operation.print()


run(test_insert_before_operation)


# CHECK-LABEL: TEST: test_insert_at_block_begin
def test_insert_at_block_begin():
    ctx = Context()
    ctx.allow_unregistered_dialects = True
    with Location.unknown(ctx):
        module = Module.parse(
            r"""
      func.func @foo() -> () {
        "custom.op2"() : () -> ()
      }
    """
        )
        entry_block = module.body.operations[0].regions[0].blocks[0]
        ip = InsertionPoint.at_block_begin(entry_block)
        ip.insert(Operation.create("custom.op1"))
        # CHECK: "custom.op1"
        # CHECK: "custom.op2"
        module.operation.print()


run(test_insert_at_block_begin)


# CHECK-LABEL: TEST: test_insert_at_block_begin_empty
def test_insert_at_block_begin_empty():
    # TODO: Write this test case when we can create such a situation.
    pass


run(test_insert_at_block_begin_empty)


# CHECK-LABEL: TEST: test_insert_at_terminator
def test_insert_at_terminator():
    ctx = Context()
    ctx.allow_unregistered_dialects = True
    with Location.unknown(ctx):
        module = Module.parse(
            r"""
      func.func @foo() -> () {
        "custom.op1"() : () -> ()
        return
      }
    """
        )
        entry_block = module.body.operations[0].regions[0].blocks[0]
        ip = InsertionPoint.at_block_terminator(entry_block)
        ip.insert(Operation.create("custom.op2"))
        # CHECK: "custom.op1"
        # CHECK: "custom.op2"
        module.operation.print()


run(test_insert_at_terminator)


# CHECK-LABEL: TEST: test_insert_at_block_terminator_missing
def test_insert_at_block_terminator_missing():
    ctx = Context()
    ctx.allow_unregistered_dialects = True
    with ctx:
        module = Module.parse(
            r"""
      func.func @foo() -> () {
        "custom.op1"() : () -> ()
      }
    """
        )
        entry_block = module.body.operations[0].regions[0].blocks[0]
        try:
            ip = InsertionPoint.at_block_terminator(entry_block)
        except ValueError as e:
            # CHECK: Block has no terminator
            print(e)
        else:
            assert False, "Expected exception"


run(test_insert_at_block_terminator_missing)


# CHECK-LABEL: TEST: test_insert_at_end_with_terminator_errors
def test_insert_at_end_with_terminator_errors():
    with Context() as ctx, Location.unknown():
        ctx.allow_unregistered_dialects = True
        module = Module.parse(
            r"""
      func.func @foo() -> () {
        return
      }
    """
        )
        entry_block = module.body.operations[0].regions[0].blocks[0]
        with InsertionPoint(entry_block):
            try:
                Operation.create("custom.op1", results=[], operands=[])
            except IndexError as e:
                # CHECK: ERROR: Cannot insert operation at the end of a block that already has a terminator.
                print(f"ERROR: {e}")


run(test_insert_at_end_with_terminator_errors)


# CHECK-LABEL: TEST: test_insertion_point_context
def test_insertion_point_context():
    ctx = Context()
    ctx.allow_unregistered_dialects = True
    with Location.unknown(ctx):
        module = Module.parse(
            r"""
      func.func @foo() -> () {
        "custom.op1"() : () -> ()
      }
    """
        )
        entry_block = module.body.operations[0].regions[0].blocks[0]
        with InsertionPoint(entry_block):
            Operation.create("custom.op2")
            with InsertionPoint.at_block_begin(entry_block):
                Operation.create("custom.opa")
                Operation.create("custom.opb")
            Operation.create("custom.op3")
        # CHECK: "custom.opa"
        # CHECK: "custom.opb"
        # CHECK: "custom.op1"
        # CHECK: "custom.op2"
        # CHECK: "custom.op3"
        module.operation.print()


run(test_insertion_point_context)
