// dirstate_map.rs

//

// Copyright 2019 Raphaël Gomès <rgomes@octobus.net>

//

// This software may be used and distributed according to the terms of the

// GNU General Public License version 2 or any later version.

use crate::dirstate::parsers::Timestamp;

use crate::{

    dirstate::EntryState,

    pack_dirstate, parse_dirstate,

    utils::hg_path::{HgPath, HgPathBuf},

    CopyMap, DirsMultiset, DirstateEntry, DirstateError, DirstateParents,

    StateMap,

};

use micro_timer::timed;

use std::collections::HashSet;

use std::iter::FromIterator;

use std::ops::Deref;

#[derive(Default)]

pub struct DirstateMap {

    state_map: StateMap,

    pub copy_map: CopyMap,

    pub dirs: Option<DirsMultiset>,

    pub all_dirs: Option<DirsMultiset>,

    non_normal_set: Option<HashSet<HgPathBuf>>,

    other_parent_set: Option<HashSet<HgPathBuf>>,

}

/// Should only really be used in python interface code, for clarity

impl Deref for DirstateMap {

    type Target = StateMap;

    fn deref(&self) -> &Self::Target {

        &self.state_map

    }

}

impl FromIterator<(HgPathBuf, DirstateEntry)> for DirstateMap {

    fn from_iter<I: IntoIterator<Item = (HgPathBuf, DirstateEntry)>>(

        iter: I,

    ) -> Self {

        Self {

            state_map: iter.into_iter().collect(),

            ..Self::default()

        }

    }

}

impl DirstateMap {

    pub fn new() -> Self {

        Self::default()

    }

    pub fn clear(&mut self) {

        self.state_map = StateMap::default();

        self.copy_map.clear();

        self.non_normal_set = None;

        self.other_parent_set = None;

    }

    /// Add a tracked file to the dirstate

    pub fn add_file(

        &mut self,

        filename: &HgPath,

        old_state: EntryState,

        entry: DirstateEntry,

    ) -> Result<(), DirstateError> {

        if old_state == EntryState::Unknown || old_state == EntryState::Removed

        {

            if let Some(ref mut dirs) = self.dirs {

                dirs.add_path(filename)?;

            }

        }

        if old_state == EntryState::Unknown {

            if let Some(ref mut all_dirs) = self.all_dirs {

                all_dirs.add_path(filename)?;

            }

        }

        self.state_map.insert(filename.to_owned(), entry.to_owned());

        if entry.is_non_normal() {

            self.get_non_normal_other_parent_entries()

                .0

                .insert(filename.to_owned());

        }

        if entry.is_from_other_parent() {

            self.get_non_normal_other_parent_entries()

                .1

                .insert(filename.to_owned());

        }

        Ok(())

    }

    /// Mark a file as removed in the dirstate.

    ///

    /// The `size` parameter is used to store sentinel values that indicate

    /// the file's previous state.  In the future, we should refactor this

    /// to be more explicit about what that state is.

    pub fn remove_file(

        &mut self,

        filename: &HgPath,

    ) -> Result<(), DirstateError> {

        if old_state != EntryState::Unknown && old_state != EntryState::Removed

        {

            if let Some(ref mut dirs) = self.dirs {

                dirs.delete_path(filename)?;

            }

        }

        if old_state == EntryState::Unknown {

            if let Some(ref mut all_dirs) = self.all_dirs {

                all_dirs.add_path(filename)?;

            }

        }

        self.state_map.insert(

            filename.to_owned(),

            DirstateEntry {

                state: EntryState::Removed,

                mode: 0,

                size,

                mtime: 0,

            },

        );

        self.get_non_normal_other_parent_entries()

            .0

            .insert(filename.to_owned());

        Ok(())

    }

    /// Remove a file from the dirstate.

    /// Returns `true` if the file was previously recorded.

    pub fn drop_file(

        &mut self,

        filename: &HgPath,

        old_state: EntryState,

    ) -> Result<bool, DirstateError> {

        let exists = self.state_map.remove(filename).is_some();

        if exists {

            if old_state != EntryState::Removed {

                if let Some(ref mut dirs) = self.dirs {

                    dirs.delete_path(filename)?;

                }

            }

            if let Some(ref mut all_dirs) = self.all_dirs {

                all_dirs.delete_path(filename)?;

            }

        }

        self.get_non_normal_other_parent_entries()

            .0

            .remove(filename);

        Ok(exists)

    }

    pub fn clear_ambiguous_times(

        &mut self,

        filenames: Vec<HgPathBuf>,

        now: i32,

    ) {

        for filename in filenames {

            if let Some(entry) = self.state_map.get_mut(&filename) {

                if entry.clear_ambiguous_mtime(now) {

                    self.get_non_normal_other_parent_entries()

                        .0

                        .insert(filename.to_owned());

                }

            }

        }

    }

    pub fn non_normal_entries_remove(&mut self, key: impl AsRef<HgPath>) {

        self.get_non_normal_other_parent_entries()

            .0

            .remove(key.as_ref());

    }

    pub fn non_normal_entries_union(

        &mut self,

        other: HashSet<HgPathBuf>,

    ) -> Vec<HgPathBuf> {

        self.get_non_normal_other_parent_entries()

            .0

            .union(&other)

            .map(ToOwned::to_owned)

            .collect()

    }

    pub fn get_non_normal_other_parent_entries(

        &mut self,

    ) -> (&mut HashSet<HgPathBuf>, &mut HashSet<HgPathBuf>) {

        self.set_non_normal_other_parent_entries(false);

        (

            self.non_normal_set.as_mut().unwrap(),

            self.other_parent_set.as_mut().unwrap(),

        )

    }

    /// Useful to get immutable references to those sets in contexts where

    /// you only have an immutable reference to the `DirstateMap`, like when

    /// sharing references with Python.

    ///

    /// TODO, get rid of this along with the other "setter/getter" stuff when

    /// a nice typestate plan is defined.

    ///

    /// # Panics

    ///

    /// Will panic if either set is `None`.

    pub fn get_non_normal_other_parent_entries_panic(

        &self,

    ) -> (&HashSet<HgPathBuf>, &HashSet<HgPathBuf>) {

        (

            self.non_normal_set.as_ref().unwrap(),

            self.other_parent_set.as_ref().unwrap(),

        )

    }

    pub fn set_non_normal_other_parent_entries(&mut self, force: bool) {

        if !force

            && self.non_normal_set.is_some()

            && self.other_parent_set.is_some()

        {

            return;

        }

        let mut non_normal = HashSet::new();

        let mut other_parent = HashSet::new();

        for (filename, entry) in self.state_map.iter() {

            if entry.is_non_normal() {

                non_normal.insert(filename.to_owned());

            }

            if entry.is_from_other_parent() {

                other_parent.insert(filename.to_owned());

            }

        }

        self.non_normal_set = Some(non_normal);

        self.other_parent_set = Some(other_parent);

    }

    /// Both of these setters and their uses appear to be the simplest way to

    /// emulate a Python lazy property, but it is ugly and unidiomatic.

    /// TODO One day, rewriting this struct using the typestate might be a

    /// good idea.

    pub fn set_all_dirs(&mut self) -> Result<(), DirstateError> {

        if self.all_dirs.is_none() {

            self.all_dirs = Some(DirsMultiset::from_dirstate(

                self.state_map.iter().map(|(k, v)| Ok((k, *v))),

                None,

            )?);

        }

        Ok(())

    }

    pub fn set_dirs(&mut self) -> Result<(), DirstateError> {

        if self.dirs.is_none() {

            self.dirs = Some(DirsMultiset::from_dirstate(

                self.state_map.iter().map(|(k, v)| Ok((k, *v))),

                Some(EntryState::Removed),

            )?);

        }

        Ok(())

    }

    pub fn has_tracked_dir(

        &mut self,

        directory: &HgPath,

    ) -> Result<bool, DirstateError> {

        self.set_dirs()?;

        Ok(self.dirs.as_ref().unwrap().contains(directory))

    }

    pub fn has_dir(

        &mut self,

        directory: &HgPath,

    ) -> Result<bool, DirstateError> {

        self.set_all_dirs()?;

        Ok(self.all_dirs.as_ref().unwrap().contains(directory))

    }

    #[timed]

    pub fn read(

        &mut self,

        file_contents: &[u8],

    ) -> Result<Option<DirstateParents>, DirstateError> {

        if file_contents.is_empty() {

            return Ok(None);

        }

        let (parents, entries, copies) = parse_dirstate(file_contents)?;

        self.state_map.extend(

            entries

                .into_iter()

                .map(|(path, entry)| (path.to_owned(), entry)),

        );

        self.copy_map.extend(

            copies

                .into_iter()

                .map(|(path, copy)| (path.to_owned(), copy.to_owned())),

        );

        Ok(Some(parents.clone()))

    }

    pub fn pack(

        &mut self,

        parents: DirstateParents,

        now: Timestamp,

    ) -> Result<Vec<u8>, DirstateError> {

        let packed =

            pack_dirstate(&mut self.state_map, &self.copy_map, parents, now)?;

        self.set_non_normal_other_parent_entries(true);

        Ok(packed)

    }

}