import copy
import ast
import gradio as gr
import modules.scripts as scripts

from modules.processing import Processed
from modules.shared import opts, cmd_opts, state # pylint: disable=unused-import


def convertExpr2Expression(expr):
    expr.lineno = 0
    expr.col_offset = 0
    result = ast.Expression(expr.value, lineno=0, col_offset = 0)

    return result


def exec_with_return(code, module):
    """
    like exec() but can return values
    https://stackoverflow.com/a/52361938/5862977
    """
    code_ast = ast.parse(code)

    init_ast = copy.deepcopy(code_ast)
    init_ast.body = code_ast.body[:-1]

    last_ast = copy.deepcopy(code_ast)
    last_ast.body = code_ast.body[-1:]

    exec(compile(init_ast, "<ast>", "exec"), module.__dict__)
    if type(last_ast.body[0]) == ast.Expr:
        return eval(compile(convertExpr2Expression(last_ast.body[0]), "<ast>", "eval"), module.__dict__)
    else:
        exec(compile(last_ast, "<ast>", "exec"), module.__dict__)


class Script(scripts.Script):

    def title(self):
        return "Custom code"

    def show(self, is_img2img):
        return cmd_opts.allow_code

    def ui(self, is_img2img):
        example = """from modules.processing import process_images

p.width = 768
p.height = 768
p.batch_size = 2
p.steps = 10

return process_images(p)
"""


        code = gr.Code(value=example, language="python", label="Python code", elem_id=self.elem_id("code"))
        indent_level = gr.Number(label='Indent level', value=2, precision=0, elem_id=self.elem_id("indent_level"))

        return [code, indent_level]

    def run(self, p, code, indent_level):
        assert cmd_opts.allow_code, '--allow-code option must be enabled'

        display_result_data = [[], -1, ""]

        def display(imgs, s=display_result_data[1], i=display_result_data[2]):
            display_result_data[0] = imgs
            display_result_data[1] = s
            display_result_data[2] = i

        from types import ModuleType
        module = ModuleType("testmodule")
        module.__dict__.update(globals())
        module.p = p
        module.display = display

        indent = " " * indent_level
        indented = code.replace('\n', f"\n{indent}")
        body = f"""def __webuitemp__():
{indent}{indented}
__webuitemp__()"""

        result = exec_with_return(body, module)

        if isinstance(result, Processed):
            return result

        return Processed(p, *display_result_data)