/**
 * Copyright (c) 2017-2022 mol* contributors, licensed under MIT, See LICENSE file for more info.
 *
 * @author Koya Sakuma < koya.sakuma.work@gmail.com>
 * @author Alexander Rose <alexander.rose@weirdbyte.de>
 *
 * Adapted from MolQL project
 **/


import * as P from '../../../mol-util/monadic-parser';
import * as h from '../helper';
import { MolScriptBuilder } from '../../../mol-script/language/builder';
const B = MolScriptBuilder;
import { properties, structureMap } from './properties';
import { operators } from './operators';
import { keywords } from './keywords';
import { AtomGroupArgs } from '../types';
import { Transpiler } from '../transpiler';
import { OperatorList } from '../types';
import { Expression } from '../../language/expression';

// <, <=, =, >=, >, !=, and LIKE
const valueOperators: OperatorList = [
    {
        '@desc': 'value comparisons',
        '@examples': [],
        name: '=',
        abbr: ['=='],
        type: h.binaryLeft,
        rule: P.MonadicParser.regexp(/\s*(LIKE|>=|<=|=|!=|>|<)\s*/i, 1),
        map: (op, e1, e2) => {
            let expr;
	    if (e1 === 'structure') {
                expr = B.core.flags.hasAny([B.ammp('secondaryStructureFlags'), structureMap(e2)]);
            } else if (e2 === 'structure') {
                expr = B.core.flags.hasAny([B.ammp('secondaryStructureFlags'), structureMap(e1)]);
            } else if (e1.head !== undefined) {
                if (e1.head.name === 'core.type.regex') {
                    expr = B.core.str.match([e1, B.core.type.str([e2])]);
                }
            } else if (e2.head !== undefined) {
                if (e2.head.name === 'core.type.regex') {
                    expr = B.core.str.match([e2, B.core.type.str([e1])]);
                }
            } else if (op.toUpperCase() === 'LIKE') {
                if (e1.head) {
                    expr = B.core.str.match([
                        B.core.type.regex([`^${e2}$`, 'i']),
                        B.core.type.str([e1])
                    ]);
                } else {
                    expr = B.core.str.match([
                        B.core.type.regex([`^${e1}$`, 'i']),
                        B.core.type.str([e2])
                    ]);
                }
            }
            if (!expr) {
                if (e1.head) e2 = h.wrapValue(e1, e2);
                if (e2.head) e1 = h.wrapValue(e2, e1);
                switch (op) {
                    case '=':
                        expr = B.core.rel.eq([e1, e2]);
                        break;
                    case '!=':
                        expr = B.core.rel.neq([e1, e2]);
                        break;
                    case '>':
                        expr = B.core.rel.gr([e1, e2]);
                        break;
                    case '<':
                        expr = B.core.rel.lt([e1, e2]);
                        break;
                    case '>=':
                        expr = B.core.rel.gre([e1, e2]);
                        break;
                    case '<=':
                        expr = B.core.rel.lte([e1, e2]);
                        break;
                    default: throw new Error(`value operator '${op}' not supported`);
                }
            }
            return B.struct.generator.atomGroups({ 'atom-test': expr });
        }
    }
];

function atomExpressionQuery(x: any[]) {
    const [resname, resno, inscode, chainname, atomname, altloc] = x[1];
    const tests: AtomGroupArgs = {};

    if (chainname) {
        // TODO: should be configurable, there is an option in Jmol to use auth or label
        tests['chain-test'] = B.core.rel.eq([B.ammp('auth_asym_id'), chainname]);
    }

    const resProps = [];
    if (resname) resProps.push(B.core.rel.eq([B.ammp('label_comp_id'), resname]));
    if (resno) resProps.push(B.core.rel.eq([B.ammp('auth_seq_id'), resno]));
    if (inscode) resProps.push(B.core.rel.eq([B.ammp('pdbx_PDB_ins_code'), inscode]));
    if (resProps.length) tests['residue-test'] = h.andExpr(resProps);

    const atomProps = [];
    if (atomname) atomProps.push(B.core.rel.eq([B.ammp('auth_atom_id'), atomname]));
    if (altloc) atomProps.push(B.core.rel.eq([B.ammp('label_alt_id'), altloc]));
    if (atomProps.length) tests['atom-test'] = h.andExpr(atomProps);

    return B.struct.generator.atomGroups(tests);
}

const lang = P.MonadicParser.createLanguage({
    Integer: () => P.MonadicParser.regexp(/-?[0-9]+/).map(Number).desc('integer'),

    Parens: function (r: any) {
        return P.MonadicParser.alt(
            r.Parens,
            r.Operator,
            r.Expression
        ).wrap(P.MonadicParser.regexp(/\(\s*/), P.MonadicParser.regexp(/\s*\)/));
    },

    Expression: function (r: any) {
        return P.MonadicParser.alt(
            r.Keywords,

            r.ResnoRange.map((x: [number, number]) => B.struct.generator.atomGroups({
                'residue-test': B.core.logic.and([
                    B.core.rel.gre([B.ammp('auth_seq_id'), x[0]]),
                    B.core.rel.lte([B.ammp('auth_seq_id'), x[1]])
                ])
            })),
            r.Resno.lookahead(P.MonadicParser.regexp(/\s*(?!(LIKE|>=|<=|!=|[\[:^%/.=><]))/i)).map((x: number) => B.struct.generator.atomGroups({
                'residue-test': B.core.rel.eq([B.ammp('auth_seq_id'), x])
            })),
            r.AtomExpression.map(atomExpressionQuery),

            r.Within.map((x: [number, Expression]) => B.struct.modifier.includeSurroundings({ 0: x[1], radius: x[0] })),
            r.ValueQuery,

            r.Element.map((x: string) => B.struct.generator.atomGroups({
                'atom-test': B.core.rel.eq([B.acp('elementSymbol'), B.struct.type.elementSymbol(x)])
            })),
            r.Resname.map((x: string) => B.struct.generator.atomGroups({
                'residue-test': B.core.rel.eq([B.ammp('label_comp_id'), x])
            })),
        );
    },

    Operator: function (r: any) {
        return h.combineOperators(operators, P.MonadicParser.alt(r.Parens, r.Expression));
    },

    AtomExpression: function (r: any) {
        return P.MonadicParser.seq(
            P.MonadicParser.lookahead(r.AtomPrefix),
            P.MonadicParser.seq(
                r.BracketedResname.or(P.MonadicParser.of(null)),
                r.Resno.or(P.MonadicParser.of(null)),
                r.Inscode.or(P.MonadicParser.of(null)),
                r.Chainname.or(P.MonadicParser.of(null)),
                r.Atomname.or(P.MonadicParser.of(null)),
                r.Altloc.or(P.MonadicParser.of(null)),
                r.Model.or(P.MonadicParser.of(null))
            )
        ).desc('expression');
    },

    AtomPrefix: () => P.MonadicParser.regexp(/[\[0-9:^%/.]/).desc('atom-prefix'),

    Chainname: () => P.MonadicParser.regexp(/:([A-Za-z]{1,3})/, 1).desc('chainname'),
    Model: () => P.MonadicParser.regexp(/\/([0-9]+)/, 1).map(Number).desc('model'),
    Element: () => P.MonadicParser.regexp(/_([A-Za-z]{1,3})/, 1).desc('element'),
    Atomname: () => P.MonadicParser.regexp(/\.([a-zA-Z0-9]{1,4})/, 1).map(B.atomName).desc('atomname'),
    Resname: () => P.MonadicParser.regexp(/[a-zA-Z0-9]{1,4}/).desc('resname'),
    Resno: (r: any) => r.Integer.desc('resno'),
    Altloc: () => P.MonadicParser.regexp(/%([a-zA-Z0-9])/, 1).desc('altloc'),
    Inscode: () => P.MonadicParser.regexp(/\^([a-zA-Z0-9])/, 1).desc('inscode'),

    BracketedResname: () => P.MonadicParser.regexp(/\[([a-zA-Z0-9]{1,4})\]/, 1).desc('bracketed-resname'),
    ResnoRange: (r: any) => {
        return P.MonadicParser.seq(
            r.Integer.skip(P.MonadicParser.seq(
                P.MonadicParser.optWhitespace,
                P.MonadicParser.string('-'),
                P.MonadicParser.optWhitespace
            )),
            r.Integer
        ).desc('resno-range');
    },
    Within: (r: any) => {
        return P.MonadicParser.regexp(/within/i)
            .skip(P.MonadicParser.regexp(/\s*\(\s*/))
            .then(P.MonadicParser.seq(
                r.Integer.skip(P.MonadicParser.regexp(/\s*,\s*/)),
                r.Query
            ))
            .skip(P.MonadicParser.regexp(/\)/));
    },

    Keywords: () => P.MonadicParser.alt(...h.getKeywordRules(keywords)).desc('keyword'),

    Query: function (r: any) {
        return P.MonadicParser.alt(
            r.Operator,
            r.Parens,
            r.Expression
        ).trim(P.MonadicParser.optWhitespace);
    },

    Number: function () {
        return P.MonadicParser.regexp(/-?(0|[1-9][0-9]*)([.][0-9]+)?([eE][+-]?[0-9]+)?/)
            .map(Number)
            .desc('number');
    },

    String: function () {
        const w = h.getReservedWords(properties, keywords, operators)
            .sort(h.strLenSortFn).map(h.escapeRegExp).join('|');
        return P.MonadicParser.alt(
            P.MonadicParser.regexp(new RegExp(`(?!(${w}))[A-Z0-9_]+`, 'i')),
            P.MonadicParser.regexp(/'((?:[^"\\]|\\.)*)'/, 1),
            P.MonadicParser.regexp(/"((?:[^"\\]|\\.)*)"/, 1).map(x => B.core.type.regex([`^${x}$`, 'i']))
        ).desc('string');
    },

    Value: function (r: any) {
        return P.MonadicParser.alt(r.Number, r.String);
    },

    ValueParens: function (r: any) {
        return P.MonadicParser.alt(
            r.ValueParens,
            r.ValueOperator,
            r.ValueExpressions
        ).wrap(P.MonadicParser.string('('), P.MonadicParser.string(')'));
    },

    ValuePropertyNames: function () {
        return P.MonadicParser.alt(...h.getPropertyNameRules(properties, /LIKE|>=|<=|=|!=|>|<|\)|\s/i));
    },

    ValueOperator: function (r: any) {
        return h.combineOperators(valueOperators, P.MonadicParser.alt(r.ValueParens, r.ValueExpressions));
    },

    ValueExpressions: function (r: any) {
        return P.MonadicParser.alt(
            r.Value,
            r.ValuePropertyNames
        );
    },

    ValueQuery: function (r: any) {
        return P.MonadicParser.alt(
            r.ValueOperator.map((x: any) => {
                if (x.head) {
                    if (x.head.name.startsWith('structure-query.generator')) return x;
                } else {
                    if (typeof x === 'string' && x.length <= 4) {
                        return B.struct.generator.atomGroups({
                            'residue-test': B.core.rel.eq([B.ammp('label_comp_id'), x])
                        });
                    }
                }
                throw new Error(`values must be part of an comparison, value '${x}'`);
            })
        );
    }
});

export const transpiler: Transpiler = str => lang.Query.tryParse(str);