// https://red-bean.com/sgf/user_guide/index.html
// https://red-bean.com/sgf/sgf4.html

// todo: support collections in a file
// Properties to support. Remove each one as it gets support.
//  B
//  KO
//  MN
//  W
//  AB
//  AE
//  AW
//  PL
//  C
//  DM
//  GB
//  GW
//  HO
//  N
//  UC
//  V
//  BM
//  DO
//  IT
//  TE
//  AR
//  CR
//  DD
//  LB
//  LN
//  MA
//  SL
//  SQ
//  TR
//  AP
//  CA
//  FF
//  GM
//  ST
//  SZ
//  AN
//  BR
//  BT
//  CP
//  DT
//  EV
//  GN
//  GC
//  ON
//  OT
//  PB
//  PC
//  PW
//  RE
//  RO
//  RU
//  SO
//  TM
//  US
//  WR
//  WT
//  BL
//  OB
//  OW
//  WL
//  FG
//  PM
//  VW

use nom::{
    bytes::complete::{tag, take_until},
    character::complete::{alpha1, anychar, multispace0},
    combinator::eof,
    multi::{many0, many1, many_till},
    sequence::{delimited, terminated},
    IResult, Parser,
};
use thiserror::Error;

pub enum Warning {}

#[derive(Debug, PartialEq, Error)]
pub enum ParseError {
    #[error("An unknown error was found")]
    UnknownError,
}

// todo: support ST root node
#[derive(Debug)]
pub struct GameTree {
    pub file_format: i8,
    pub app: Option<String>,
    pub game_type: GameType,
    pub board_size: Size,

    pub text: String,
}

pub struct GameInfo {
    pub annotator: Option<String>,
    pub copyright: Option<String>,
    pub event: Option<String>,
    // Games can be played across multiple days, even multiple years. The format specifies
    // shortcuts.
    pub date_time: Vec<chrono::NaiveDate>,
    pub location: Option<String>,
    // special rules for the round-number and type
    pub round: Option<String>,
    pub ruleset: Option<String>,
    pub source: Option<String>,
    pub time_limits: Option<std::time::Duration>,
    pub game_keeper: Option<String>,

    pub game_name: Option<String>,
    pub game_comments: Option<String>,

    pub black_player: Option<String>,
    pub black_rank: Option<String>,
    pub black_team: Option<String>,

    pub white_player: Option<String>,
    pub white_rank: Option<String>,
    pub white_team: Option<String>,

    pub opening: Option<String>,
    pub overtime: Option<String>,
    pub result: Option<GameResult>,
}

pub enum GameResult {
    Annulled,
    Draw,
    Black(Win),
    White(Win),
}

pub enum Win {
    Score(i32),
    Resignation,
    Forfeit,
    Time,
}

#[derive(Debug, PartialEq)]
pub struct Size {
    width: i32,
    height: i32,
}

#[derive(Debug, PartialEq)]
pub enum GameType {
    Go,
    Unsupported,
}

struct Sequence(Node);

/*
struct Node {
    // properties
}
*/

enum PropType {
    Move,
    Setup,
    Root,
    GameInfo,
}

enum PropValue {
    Empty,
    Number,
    Real,
    Double,
    Color,
    SimpleText,
    Text,
    Point,
    Move,
    Stone,
}

#[derive(Debug, PartialEq)]
struct Tree {
    sequence: Vec<Node>,
    sub_sequences: Vec<Tree>,
}

impl ToString for Tree {
    fn to_string(&self) -> String {
        let sequence = self
            .sequence
            .iter()
            .map(|node| node.to_string())
            .collect::<String>();
        let subsequences = self
            .sub_sequences
            .iter()
            .map(|seq| seq.to_string())
            .collect::<String>();
        format!("({}{})", sequence, subsequences)
    }
}

#[derive(Debug, PartialEq)]
struct Node {
    properties: Vec<Property>,
}

impl ToString for Node {
    fn to_string(&self) -> String {
        let props = self
            .properties
            .iter()
            .map(|prop| prop.to_string())
            .collect::<String>();
        format!(";{}", props)
    }
}

#[derive(Debug, PartialEq)]
struct Property {
    ident: String,
    values: Vec<String>,
}

impl ToString for Property {
    fn to_string(&self) -> String {
        let values = self
            .values
            .iter()
            .map(|val| format!("[{}]", val))
            .collect::<String>();
        format!("{}{}", self.ident, values)
    }
}

// note: must preserve unknown properties
// note: must fix or preserve illegally formatted game-info properties
// note: must correct or delete illegally foramtted properties, but display a warning
/*
pub fn parse_sgf(input: &str) -> Result<(GameTree, Vec<Warning>), ParseError> {
    let (_, gameinfo) = parse_gametree(input).unwrap();
    Ok((gameinfo, vec![]))
}
*/

fn parse_tree(input: &str) -> IResult<&str, Tree> {
    println!("parse_tree: {}", input);
    let (input, _) = multispace0(input)?;
    delimited(tag("("), parse_sequence, tag(")"))(input)
}

fn parse_sequence(input: &str) -> IResult<&str, Tree> {
    println!("parse_sequence: {}", input);
    let (input, _) = multispace0(input)?;
    let (input, nodes) = many1(parse_node)(input)?;
    let (input, sub_sequences) = many0(parse_tree)(input)?;

    Ok((
        input,
        Tree {
            sequence: nodes,
            sub_sequences,
        },
    ))
}

fn parse_node(input: &str) -> IResult<&str, Node> {
    println!("parse_node: {}", input);
    let (input, _) = multispace0(input)?;
    let (input, _) = tag(";")(input)?;
    let (input, properties) = many1(parse_property)(input)?;
    Ok((input, Node { properties }))
}

fn parse_property(input: &str) -> IResult<&str, Property> {
    println!("parse_property: {}", input);
    let (input, ident) = alpha1(input)?;
    let (input, values) = many1(delimited(tag("["), take_until("]"), tag("]")))(input)?;

    let values = values
        .into_iter()
        .map(|v| v.to_owned())
        .collect::<Vec<String>>();
    Ok((
        input,
        Property {
            ident: ident.to_owned(),
            values,
        },
    ))
}

/*
fn parse_gametree(input: &str) -> IResult<&str, GameTree> {
    let (input, _) = tag("(;")(input)?;
    let (input, properties) = many1(parse_property)(input)?;
    let (input, _) = tag(")")(input)?;
    println!("properties: {:?}", properties);
    Ok((input, unimplemented!()))
}

*/

pub fn add(left: usize, right: usize) -> usize {
    left + right
}

#[cfg(test)]
mod tests {
    use super::*;

    const EXAMPLE_1: &'static str = "(;FF[4]C[root](;C[a];C[b](;C[c])
(;C[d];C[e]))
(;C[f](;C[g];C[h];C[i])
(;C[j])))";

    const EXAMPLE_2: &'static str = "(;FF[4]GM[1]SZ[19]AP[SGFC:1.13b]

PB[troy]BR[12k*]
PW[john]WR[11k*]
KM[0.5]RE[W+12.5]
DT[1998-06-15]
TM[600]

;B[pd];W[dp];B[pq];W[dd];B[qk];W[jd];B[fq];W[dj];B[jp];W[jj]
;B[cn]LB[dn:A][po:B]C[dada: other ideas are 'A' (d6) or 'B' (q5)]
;W[eo](;B[dl]C[dada: hm - looks troublesome.
Usually B plays the 3,3 invasion - see variation];W[qo];B[qp]
...
;W[sr];B[sk];W[sg];B[pa];W[gc];B[pi];W[ph];B[de];W[ed];B[kn]
;W[dh];B[eh];W[se];B[sd];W[af];B[ie];W[id];B[hf];W[hd];B[if]
;W[fp];B[gq];W[qj];B[sj];W[rh];B[sn];W[so];B[sm];W[ep];B[mn])
...
(;W[dq]N[wrong direction];B[qo];W[qp]))";

    #[test]
    fn it_can_parse_properties() {
        let (_, prop) = parse_property("C[a]").unwrap();
        assert_eq!(
            prop,
            Property {
                ident: "C".to_owned(),
                values: vec!["a".to_owned()]
            }
        );

        let (_, prop) = parse_property("C[a][b][c]").unwrap();
        assert_eq!(
            prop,
            Property {
                ident: "C".to_owned(),
                values: vec!["a".to_owned(), "b".to_owned(), "c".to_owned()]
            }
        );
    }

    #[test]
    fn it_can_parse_a_standalone_node() {
        let (_, node) = parse_node(";B[ab]").unwrap();

        assert_eq!(
            node,
            Node {
                properties: vec![Property {
                    ident: "B".to_owned(),
                    values: vec!["ab".to_owned()]
                }]
            }
        );

        let (_, node) = parse_node(";B[ab];W[dp];B[pq]C[some comments]").unwrap();

        assert_eq!(
            node,
            Node {
                properties: vec![Property {
                    ident: "B".to_owned(),
                    values: vec!["ab".to_owned()]
                }]
            }
        );
    }

    #[test]
    fn it_can_parse_a_simple_sequence() {
        let (_, sequence) = parse_tree("(;B[ab];W[dp];B[pq]C[some comments])").unwrap();

        assert_eq!(
            sequence,
            Tree {
                sequence: vec![
                    Node {
                        properties: vec![Property {
                            ident: "B".to_owned(),
                            values: vec!["ab".to_owned()]
                        }]
                    },
                    Node {
                        properties: vec![Property {
                            ident: "W".to_owned(),
                            values: vec!["dp".to_owned()]
                        }]
                    },
                    Node {
                        properties: vec![
                            Property {
                                ident: "B".to_owned(),
                                values: vec!["pq".to_owned()]
                            },
                            Property {
                                ident: "C".to_owned(),
                                values: vec!["some comments".to_owned()]
                            }
                        ]
                    }
                ],
                sub_sequences: vec![],
            }
        );
    }

    #[test]
    fn it_can_parse_a_sequence_with_subsequences() {
        let text = "(;C[a];C[b](;C[c])(;C[d];C[e]))";
        let (_, sequence) = parse_tree(text).unwrap();

        let main_sequence = vec![
            Node {
                properties: vec![Property {
                    ident: "C".to_owned(),
                    values: vec!["a".to_owned()],
                }],
            },
            Node {
                properties: vec![Property {
                    ident: "C".to_owned(),
                    values: vec!["b".to_owned()],
                }],
            },
        ];
        let subsequence_1 = Tree {
            sequence: vec![Node {
                properties: vec![Property {
                    ident: "C".to_owned(),
                    values: vec!["c".to_owned()],
                }],
            }],
            sub_sequences: vec![],
        };
        let subsequence_2 = Tree {
            sequence: vec![
                Node {
                    properties: vec![Property {
                        ident: "C".to_owned(),
                        values: vec!["d".to_owned()],
                    }],
                },
                Node {
                    properties: vec![Property {
                        ident: "C".to_owned(),
                        values: vec!["e".to_owned()],
                    }],
                },
            ],
            sub_sequences: vec![],
        };

        assert_eq!(
            sequence,
            Tree {
                sequence: main_sequence,
                sub_sequences: vec![subsequence_1, subsequence_2],
            }
        );
    }

    #[test]
    fn it_can_parse_example_1() {
        let (_, ex_tree) = parse_tree(EXAMPLE_1).unwrap();
        assert_eq!(ex_tree.sequence.len(), 1);

        assert_eq!(ex_tree.sequence[0].properties.len(), 2);
        assert_eq!(
            ex_tree.sequence[0].properties[0],
            Property {
                ident: "FF".to_owned(),
                values: vec!["4".to_owned()]
            }
        );
        assert_eq!(ex_tree.sub_sequences.len(), 2);

        assert_eq!(ex_tree.sub_sequences[0].sequence.len(), 2);
        assert_eq!(
            ex_tree.sub_sequences[0].sequence,
            vec![
                Node {
                    properties: vec![Property {
                        ident: "C".to_owned(),
                        values: vec!["a".to_owned()]
                    }]
                },
                Node {
                    properties: vec![Property {
                        ident: "C".to_owned(),
                        values: vec!["b".to_owned()]
                    }]
                },
            ]
        );
        assert_eq!(ex_tree.sub_sequences[0].sub_sequences.len(), 2);
    }

    #[test]
    fn it_can_regenerate_the_tree() {
        let (_, tree1) = parse_tree(EXAMPLE_1).unwrap();
        println!("{}", tree1.to_string());
        assert_eq!(
            tree1.to_string(),
            "(;FF[4]C[root](;C[a];C[b](;C[c])(;C[d];C[e]))(;C[f](;C[g];C[h];C[i])(;C[j])))"
        );
        let (_, tree2) = parse_tree(&tree1.to_string()).unwrap();
        assert_eq!(tree1, tree2);
    }

    /*
    fn with_examples(f: impl FnOnce(GameTree, GameTree)) {
        let (example_1, _) = parse_sgf(EXAMPLE_1).unwrap();
        let (example_2, _) = parse_sgf(EXAMPLE_2).unwrap();

        f(example_1, example_2);
    }

    #[test]
    fn it_parses_game_root() {
        with_examples(|ex_1, ex_2| {
            assert_eq!(ex_1.file_format, 4);
            assert_eq!(ex_1.app, None);
            assert_eq!(ex_1.game_type, GameType::Go);
            assert_eq!(
                ex_1.board_size,
                Size {
                    width: 19,
                    height: 19
                }
            );
            assert_eq!(ex_1.text, EXAMPLE_1.to_owned());

            assert_eq!(ex_2.file_format, 4);
            assert_eq!(ex_2.app, Some("SGFC:1.13b".to_owned()));
            assert_eq!(ex_2.game_type, GameType::Go);
            assert_eq!(
                ex_2.board_size,
                Size {
                    width: 19,
                    height: 19
                }
            );
            assert_eq!(ex_2.text, EXAMPLE_2.to_owned());
        });
    }
    */
}