use cpython::exc;

use cpython::PyBytes;

use cpython::PyErr;

use cpython::PyNone;

use cpython::PyObject;

use cpython::PyResult;

use cpython::Python;

use cpython::PythonObject;

use hg::dirstate::DirstateEntry;

use hg::dirstate::EntryState;

use std::cell::Cell;

use std::convert::TryFrom;

py_class!(pub class DirstateItem |py| {

    data entry: Cell<DirstateEntry>;

    def __new__(

        _cls,

        wc_tracked: bool = false,

        p1_tracked: bool = false,

        p2_info: bool = false,

        has_meaningful_data: bool = true,

        has_meaningful_mtime: bool = true,

        parentfiledata: Option<(i32, i32, i32)> = None,

    ) -> PyResult<DirstateItem> {

        let mut mode_size_opt = None;

        let mut mtime_opt = None;

        if let Some((mode, size, mtime)) = parentfiledata {

            if has_meaningful_data {

                mode_size_opt = Some((mode, size))

            }

            if has_meaningful_mtime {

                mtime_opt = Some(mtime)

            }

        }

        let entry = DirstateEntry::from_v2_data(

            wc_tracked, p1_tracked, p2_info, mode_size_opt, mtime_opt,

        );

        DirstateItem::create_instance(py, Cell::new(entry))

    }

    @property

    def state(&self) -> PyResult<PyBytes> {

        let state_byte: u8 = self.entry(py).get().state().into();

        Ok(PyBytes::new(py, &[state_byte]))

    }

    @property

    def mode(&self) -> PyResult<i32> {

        Ok(self.entry(py).get().mode())

    }

    @property

    def size(&self) -> PyResult<i32> {

        Ok(self.entry(py).get().size())

    }

    @property

    def mtime(&self) -> PyResult<i32> {

        Ok(self.entry(py).get().mtime())

    }

    @property

    def tracked(&self) -> PyResult<bool> {

        Ok(self.entry(py).get().tracked())

    }

    @property

    def p1_tracked(&self) -> PyResult<bool> {

        Ok(self.entry(py).get().p1_tracked())

    }

    @property

    def added(&self) -> PyResult<bool> {

        Ok(self.entry(py).get().added())

    }

    @property

    def p2_info(&self) -> PyResult<bool> {

        Ok(self.entry(py).get().p2_info())

    }

    @property

    def removed(&self) -> PyResult<bool> {

        Ok(self.entry(py).get().removed())

    }

    @property

    def maybe_clean(&self) -> PyResult<bool> {

        Ok(self.entry(py).get().maybe_clean())

    }

    @property

    def any_tracked(&self) -> PyResult<bool> {

        Ok(self.entry(py).get().any_tracked())

    }

    def v1_state(&self) -> PyResult<PyBytes> {

        let (state, _mode, _size, _mtime) = self.entry(py).get().v1_data();

        let state_byte: u8 = state.into();

        Ok(PyBytes::new(py, &[state_byte]))

    }

    def v1_mode(&self) -> PyResult<i32> {

        let (_state, mode, _size, _mtime) = self.entry(py).get().v1_data();

        Ok(mode)

    }

    def v1_size(&self) -> PyResult<i32> {

        let (_state, _mode, size, _mtime) = self.entry(py).get().v1_data();

        Ok(size)

    }

    def v1_mtime(&self) -> PyResult<i32> {

        let (_state, _mode, _size, mtime) = self.entry(py).get().v1_data();

        Ok(mtime)

    }

    def need_delay(&self, now: i32) -> PyResult<bool> {

        Ok(self.entry(py).get().mtime_is_ambiguous(now))

    }

    @classmethod

    def from_v1_data(

        _cls,

        state: PyBytes,

        mode: i32,

        size: i32,

        mtime: i32,

    ) -> PyResult<Self> {

        let state = <[u8; 1]>::try_from(state.data(py))

            .ok()

            .and_then(|state| EntryState::try_from(state[0]).ok())

            .ok_or_else(|| PyErr::new::<exc::ValueError, _>(py, "invalid state"))?;

        let entry = DirstateEntry::from_v1_data(state, mode, size, mtime);

        DirstateItem::create_instance(py, Cell::new(entry))

    }

    @classmethod

    def new_possibly_dirty(_cls) -> PyResult<Self> {

        let entry = DirstateEntry::new_possibly_dirty();

        DirstateItem::create_instance(py, Cell::new(entry))

    }

    @classmethod

    def new_normal(_cls, mode: i32, size: i32, mtime: i32) -> PyResult<Self> {

        let entry = DirstateEntry::new_normal(mode, size, mtime);

        DirstateItem::create_instance(py, Cell::new(entry))

    }

    def drop_merge_data(&self) -> PyResult<PyNone> {

        self.update(py, |entry| entry.drop_merge_data());

        Ok(PyNone)

    }

    def set_clean(

        &self,

        mode: i32,

        size: i32,

        mtime: i32,

    ) -> PyResult<PyNone> {

        self.update(py, |entry| entry.set_clean(mode, size, mtime));

        Ok(PyNone)

    }

    def set_possibly_dirty(&self) -> PyResult<PyNone> {

        self.update(py, |entry| entry.set_possibly_dirty());

        Ok(PyNone)

    }

    def set_tracked(&self) -> PyResult<PyNone> {

        self.update(py, |entry| entry.set_tracked());

        Ok(PyNone)

    }

    def set_untracked(&self) -> PyResult<PyNone> {

        self.update(py, |entry| entry.set_untracked());

        Ok(PyNone)

    }

});

impl DirstateItem {

    pub fn new_as_pyobject(

        py: Python<'_>,

        entry: DirstateEntry,

    ) -> PyResult<PyObject> {

        Ok(DirstateItem::create_instance(py, Cell::new(entry))?.into_object())

    }

    pub fn get_entry(&self, py: Python<'_>) -> DirstateEntry {

        self.entry(py).get()

    }

    // TODO: Use https://doc.rust-lang.org/std/cell/struct.Cell.html#method.update instead when it’s stable

    pub fn update(&self, py: Python<'_>, f: impl FnOnce(&mut DirstateEntry)) {

        let mut entry = self.entry(py).get();

        f(&mut entry);

        self.entry(py).set(entry)

    }

}