from collections.abc import Callable, Sequence

from pynvim import Nvim, command, plugin
from pynvim.api import Buffer

from .clickup import ClickupSession
from .hints import JSONData
from .yaml import load, dump


def usernames_from_objs(objs: JSONData) -> JSONData:
    assert isinstance(objs, list)
    return [k["username"] for k in objs if isinstance(k, dict)]


@plugin
class MrPyPlugin:
    nvim: Nvim
    clickup: ClickupSession
    frontmatter_keys: dict[str, Callable[[JSONData], JSONData]]

    def __init__(self, nvim: Nvim) -> None:
        self.nvim = nvim
        self.clickup = ClickupSession()
        self.frontmatter_keys = {
            "id": str,
            "name": str,
            "assignees": usernames_from_objs,
        }

    def select_task_id(self) -> None:
        tasks = self.clickup.get_tasks()
        task_names_by_id = [
            {
                "idx": tix + 1,
                "id": t.id,
                "name": t.name,
                "status": t.status,
                "is_child": bool(t.parent),
                "preview": {
                    "text": f"---\n{dump(t.showables)}---\n{t.markdown_description}",
                    "ft": "markdown",
                },
                "action": f":Mrpy {t.id}",
            }
            for tix, t in enumerate(tasks)
            if not t.name.endswith("Absence")
        ]

        self.nvim.exec_lua(
            """require('snacks').picker.pick({
                title="Select Task",
                format = function(item, _)
				    local ret = {}

					local hl = "SnacksPickerComment"
					if item.status == "in progress" then
					    hl = "@method"
					elseif item.status == "selected for development" then
					    hl = "@constant.builtin"
					elseif item.status == "in review" then
					    hl = "@keyword"
					elseif item.status == "done" then
					    hl = "@variable.builtin"
					end

					if item.is_child == true then
				        ret[#ret + 1] = {  "󰘍 ", "SnacksPickerComment" }
					end

				    ret[#ret + 1] = { item.name, hl }

				    ret[#ret + 1] = {
					    " (#" .. item.id .. ")",
					    "SnacksPickerComment"
				    }
				    return ret
			    end,
                preview="preview",
                confirm=function(_, item) vim.cmd(("Mrpy %s"):format(item.id)) end,
                items=...
            })""",
            task_names_by_id,
        )

    def open_task_buffer(self, task_id: str) -> None:
        if " " in task_id:
            *_, last = task_id.split(" ")
            task_id = last.removeprefix("(#").removesuffix(")")

        task = self.clickup.get_task(task_id)
        temp_buf: Buffer = self.nvim.api.create_buf(True, False)
        self.nvim.api.buf_set_name(temp_buf, f"[ClickUp] {task.name}")
        self.nvim.buffers[temp_buf.number].options["filetype"] = "markdown"
        self.nvim.api.create_autocmd(
            ["BufWriteCmd"],
            {"buffer": temp_buf.number, "command": "MrpyPush " + str(temp_buf.number)},
        )

        content = ["---"]
        content.extend(
            dump(
                task.showables,
            ).splitlines()
        )
        content.append("---")
        content.extend(task.markdown_description.splitlines())

        self.nvim.api.buf_set_lines(temp_buf, 0, 0, False, content)
        self.nvim.buffers[temp_buf.number].options["modified"] = False
        self.nvim.api.win_set_buf(0, temp_buf)

    @command("Mrpy", nargs="?")
    def entry(self, args: Sequence[str] = ()) -> None:
        match args:
            case (str() as task_id,):
                self.open_task_buffer(task_id)
            case ():
                self.select_task_id()
            case _:
                pass

    @command("MrpyPush", nargs="?")
    def on_vbuf_write(self, args: Sequence[str] = ()) -> None:
        match args:
            case "0", *_:
                return
            case buf_no, *_:
                buf_no = int(buf_no)
            case _:
                return

        try:
            a = self.nvim.buffers[buf_no][0:-1]
            _, fm, *text = "\n".join(a).split("---\n")
            data = load(fm)
            assert isinstance(data, dict)

            data["markdown_description"] = "\n\n".join(text)

            self.nvim.err_write(str(data) + "\n")
            # self.clickup.update(data)
            self.nvim.buffers[buf_no].options["modified"] = False
        except ValueError:
            pass