/**
 * Copyright (c) 2017-2018 mol* contributors, licensed under MIT, See LICENSE file for more info.
 *
 * @author Alexander Rose <alexander.rose@weirdbyte.de>
 */

import { Database, Column, EnumCol, StrCol, IntCol, ListCol, FloatCol, CoordCol, MatrixCol, VectorCol } from './schema';
import { parseImportGet } from './helper';
import * as Data from '../../../mol-io/reader/cif/data-model';
import { CifFrame } from '../../../mol-io/reader/cif/data-model';

export function getFieldType(type: string, description: string, values?: string[], container?: string): Column {
    switch (type) {
        // mmCIF
        case 'code':
        case 'ucode':
        case 'line':
        case 'uline':
        case 'text':
        case 'char':
        case 'uchar3':
        case 'uchar1':
        case 'boolean':
            return values && values.length ? EnumCol(values, 'str', description) : StrCol(description);
        case 'aliasname':
        case 'name':
        case 'idname':
        case 'any':
        case 'atcode':
        case 'fax':
        case 'phone':
        case 'email':
        case 'code30':
        case 'seq-one-letter-code':
        case 'author':
        case 'orcid_id':
        case 'pdbx_PDB_obsoleted_db_id':
        case 'pdbx_related_db_id':
        case 'sequence_dep':
        case 'pdb_id':
        case 'emd_id':
        // todo, consider adding specialised fields
        case 'yyyy-mm-dd':
        case 'yyyy-mm-dd:hh:mm':
        case 'yyyy-mm-dd:hh:mm-flex':
        case 'int-range':
        case 'float-range':
        case 'binary':
        case 'operation_expression':
        case 'point_symmetry':
        case '4x3_matrix':
        case '3x4_matrices':
        case 'point_group':
        case 'point_group_helical':
        case 'symmetry_operation':
        case 'date_dep':
        case 'url':
        case 'symop':
        case 'exp_data_doi':
        case 'asym_id':
            return StrCol(description);
        case 'int':
        case 'non_negative_int':
        case 'positive_int':
            return values && values.length ? EnumCol(values, 'int', description) : IntCol(description);
        case 'float':
            return FloatCol(description);
        case 'ec-type':
        case 'ucode-alphanum-csv':
        case 'id_list':
            return ListCol('str', ',', description);
        case 'id_list_spc':
            return ListCol('str', ' ', description);

        // cif
        case 'Text':
        case 'Code':
        case 'Complex':
        case 'Symop':
        case 'List':
        case 'List(Real,Real)':
        case 'List(Real,Real,Real,Real)':
        case 'Date':
        case 'DateTime':
        case 'Tag':
        case 'Implied':
            return wrapContainer('str', ',', description, container);
        case 'Real':
            return wrapContainer('float', ',', description, container);
        case 'Integer':
            return wrapContainer('int', ',', description, container);

    }
    console.log(`unknown type '${type}'`);
    return StrCol(description);
}

function ColFromType(type: 'int' | 'str' | 'float' | 'coord', description: string): Column {
    switch (type) {
        case 'int': return IntCol(description);
        case 'str': return StrCol(description);
        case 'float': return FloatCol(description);
        case 'coord': return CoordCol(description);
    }
}

function wrapContainer(type: 'int' | 'str' | 'float' | 'coord', separator: string, description: string, container?: string) {
    return container && container === 'List' ? ListCol(type, separator, description) : ColFromType(type, description);
}

type FrameCategories = { [category: string]: Data.CifFrame }
type FrameLinks = { [k: string]: string }

interface FrameData {
    categories: FrameCategories
    links: FrameLinks
}

type Imports = Map<string, CifFrame[]>

function getImportFrames(d: Data.CifFrame, imports: Imports) {
    const frames: Data.CifFrame[] = [];
    if (!('import' in d.categories)) return frames;

    const importGet = parseImportGet(d.categories['import'].getField('get')!.str(0));
    for (const g of importGet) {
        const { file, save } = g;
        if (!file || !save) {
            console.warn(`missing 'save' or 'file' for import in '${d.header}'`);
            continue;
        }
        const importFrames = imports.get(file);
        if (!importFrames) {
            console.warn(`missing '${file}' entry in imports`);
            continue;
        }
        const importSave = importFrames.find(id => id.header.toLowerCase() === save.toLowerCase());
        if (!importSave) {
            console.warn(`missing '${save}' save frame in '${file}'`);
            continue;
        }

        frames.push(importSave);
    }

    return frames;
}

/** get field from given or linked category */
function getField(category: string, field: string, d: Data.CifFrame, imports: Imports, ctx: FrameData): Data.CifField|undefined {
    const { categories, links } = ctx;
    const cat = d.categories[category];
    if (cat) {
        return cat.getField(field);
    } else if (d.header in links) {
        const linkName = links[d.header];
        if (linkName in categories) {
            return getField(category, field, categories[linkName], imports, ctx);
        } else {
            // console.log(`link '${linkName}' not found`)
        }
    } else {
        const importFrames = getImportFrames(d, imports);
        for (const idf of importFrames) {
            return getField(category, field, idf, imports, ctx);
        }
    }
}

function getEnums(d: Data.CifFrame, imports: Imports, ctx: FrameData) {
    const value = getField('item_enumeration', 'value', d, imports, ctx);
    const enums: string[] = [];
    if (value) {
        for (let i = 0; i < value.rowCount; ++i) {
            enums.push(value.str(i));
            // console.log(value.str(i))
        }
        return enums;
    } else {
        // console.log(`item_enumeration.value not found for '${d.header}'`)
    }
}

function getContainer(d: Data.CifFrame, imports: Imports, ctx: FrameData) {
    const value = getField('type', 'container', d, imports, ctx);
    return value ? value.str(0) : undefined;
}

function getCode(d: Data.CifFrame, imports: Imports, ctx: FrameData): [string, string[] | undefined, string | undefined ] | undefined {
    const code = getField('item_type', 'code', d, imports, ctx) || getField('type', 'contents', d, imports, ctx);
    if (code) {
        return [code.str(0), getEnums(d, imports, ctx), getContainer(d, imports, ctx)];
    } else {
        console.log(`item_type.code or type.contents not found for '${d.header}'`);
    }
}

function getSubCategory(d: Data.CifFrame, imports: Imports, ctx: FrameData): string | undefined {
    const value = getField('item_sub_category', 'id', d, imports, ctx);
    if (value) {
        return value.str(0);
    }
}

function getDescription(d: Data.CifFrame, imports: Imports, ctx: FrameData): string | undefined {
    const value = getField('item_description', 'description', d, imports, ctx) || getField('description', 'text', d, imports, ctx);
    if (value) {
        // trim (after newlines) and remove references to square brackets
        return value.str(0).trim()
            .replace(/(\r\n|\r|\n)([ \t]+)/g, '\n')
            .replace(/(\[[1-3]\])+ element/, 'elements')
            .replace(/(\[[1-3]\])+/, '');
    }
}

function getAliases(d: Data.CifFrame, imports: Imports, ctx: FrameData): string[] | undefined {
    const value = getField('item_aliases', 'alias_name', d, imports, ctx) || getField('alias', 'definition_id', d, imports, ctx);
    return value ? value.toStringArray().map(v => v.substr(1)) : undefined;
}

const reMatrixField = /\[[1-3]\]\[[1-3]\]/;
const reVectorField = /\[[1-3]\]/;

const FORCE_INT_FIELDS = [
    '_atom_site.id',
    '_atom_site.auth_seq_id',
    '_atom_site_anisotrop.id',
    '_pdbx_struct_mod_residue.auth_seq_id',
    '_struct_conf.beg_auth_seq_id',
    '_struct_conf.end_auth_seq_id',
    '_struct_conn.ptnr1_auth_seq_id',
    '_struct_conn.ptnr2_auth_seq_id',
    '_struct_sheet_range.beg_auth_seq_id',
    '_struct_sheet_range.end_auth_seq_id',
];

/**
 * Note that name and mapped name must share a prefix. This is not always the case in
 * the cifCore dictionary, but for downstream code to work a container field with the
 * same prefix as the member fields must be given here and in the field names filter
 * list.
 */
const FORCE_MATRIX_FIELDS_MAP: { [k: string]: string } = {
    'atom_site_aniso.u_11': 'u', // is matrix_u in the the dic
    'atom_site_aniso.u_22': 'u',
    'atom_site_aniso.u_33': 'u',
    'atom_site_aniso.u_23': 'u',
    'atom_site_aniso.u_13': 'u',
    'atom_site_aniso.u_12': 'u',
};
const FORCE_MATRIX_FIELDS = Object.keys(FORCE_MATRIX_FIELDS_MAP);

const EXTRA_ALIASES: Database['aliases'] = {
    'atom_site_aniso.matrix_u': [
        'atom_site_anisotrop_U',
        'atom_site_aniso.U'
    ],
};

const COMMA_SEPARATED_LIST_FIELDS = [
    '_atom_site.pdbx_struct_group_id',
    '_chem_comp.mon_nstd_parent_comp_id',
    '_diffrn_radiation.pdbx_wavelength_list',
    '_diffrn_source.pdbx_wavelength_list',
    '_em_diffraction.tilt_angle_list', // 20,40,50,55
    '_em_entity_assembly.entity_id_list',
    '_entity.pdbx_description', // Endolysin,Beta-2 adrenergic receptor
    '_entity.pdbx_ec',
    '_entity_poly.pdbx_strand_id', // A,B
    '_entity_src_gen.pdbx_gene_src_gene', // ADRB2, ADRB2R, B2AR
    '_pdbx_depui_entry_details.experimental_methods',
    '_pdbx_depui_entry_details.requested_accession_types',
    '_pdbx_soln_scatter_model.software_list', // INSIGHT II, HOMOLOGY, DISCOVERY, BIOPOLYMER, DELPHI
    '_pdbx_soln_scatter_model.software_author_list', // MSI
    '_pdbx_soln_scatter_model.entry_fitting_list', // Odd example: 'PDB CODE 1HFI, 1HCC, 1HFH, 1VCC'
    '_pdbx_struct_assembly_gen.entity_inst_id',
    '_pdbx_struct_assembly_gen.asym_id_list',
    '_pdbx_struct_assembly_gen.auth_asym_id_list',
    '_pdbx_struct_assembly_gen_depositor_info.asym_id_list',
    '_pdbx_struct_assembly_gen_depositor_info.chain_id_list',
    '_pdbx_struct_group_list.group_enumeration_type',
    '_reflns.pdbx_diffrn_id',
    '_refine.pdbx_diffrn_id',
    '_reflns_shell.pdbx_diffrn_id',
    '_struct_keywords.text',
];

const SPACE_SEPARATED_LIST_FIELDS = [
    '_chem_comp.pdbx_subcomponent_list', // TSM DPH HIS CHF EMR
    '_pdbx_soln_scatter.data_reduction_software_list', // OTOKO
    '_pdbx_soln_scatter.data_analysis_software_list', // SCTPL5 GNOM
];

const SEMICOLON_SEPARATED_LIST_FIELDS = [
    '_chem_comp.pdbx_synonyms' // GLYCERIN; PROPANE-1,2,3-TRIOL
];

/**
 * Useful when a dictionary extension will add enum values to an existing dictionary.
 * By adding them here, the dictionary extension can be tested before the added enum
 * values are available in the existing dictionary.
 */
const EXTRA_ENUM_VALUES: { [k: string]: string[] } = {

};

export function generateSchema(frames: CifFrame[], imports: Imports = new Map()): Database {
    const tables: Database['tables'] = {};
    const aliases: Database['aliases'] = { ...EXTRA_ALIASES };

    const categories: FrameCategories = {};
    const links: FrameLinks = {};
    const ctx = { categories, links };

    // get category metadata
    frames.forEach(d => {
        // category definitions in mmCIF start with '_' and don't include a '.'
        // category definitions in cifCore don't include a '.'
        if (d.header[0] === '_'  || d.header.includes('.')) return;
        const categoryName = d.header.toLowerCase();
        // console.log(d.header, d.categoryNames, d.categories)
        let descriptionField: Data.CifField | undefined;
        const categoryKeyNames = new Set<string>();

        if ('category' in d.categories && 'category_key' in d.categories) {
            const category = d.categories['category'];
            const categoryKey = d.categories['category_key'];
            if (categoryKey) {
                const categoryKey_names = categoryKey.getField('name');
                if (categoryKey_names) {
                    for (let i = 0, il = categoryKey_names.rowCount; i < il; ++i) {
                        categoryKeyNames.add(categoryKey_names.str(i));
                    }
                }
            }

            descriptionField = category.getField('description');

            if (categoryKeyNames.size === 0) {
                console.log(`no key given for category '${categoryName}'`);
            }
        }

        if ('description' in d.categories) {
            descriptionField = d.categories['description'].getField('text');
        }

        let description = '';
        if (descriptionField) {
            description = descriptionField.str(0).trim()
                .replace(/(\r\n|\r|\n)([ \t]+)/g, '\n'); // remove padding after newlines
        } else {
            console.log(`no description given for category '${categoryName}'`);
        }

        tables[categoryName] = { description, key: categoryKeyNames, columns: {} };

        // console.log('++++++++++++++++++++++++++++++++++++++++++')
        // console.log('name', categoryName)
        // console.log('desc', description)
        // console.log('key', categoryKeyNames)
    });

    // build list of links between categories
    frames.forEach(d => {
        if (d.header[0] !== '_' && !d.header.includes('.')) return;
        categories[d.header] = d;
        const item_linked = d.categories['item_linked'];
        if (item_linked) {
            const child_name = item_linked.getField('child_name');
            const parent_name = item_linked.getField('parent_name');
            if (child_name && parent_name) {
                for (let i = 0; i < item_linked.rowCount; ++i) {
                    const childName: string = child_name.str(i);
                    const parentName = parent_name.str(i);
                    if (childName in links && links[childName] !== parentName) {
                        console.log(`${childName} linked to ${links[childName]}, ignoring link to ${parentName}`);
                    }
                    links[childName] = parentName;
                }
            }
        }
    });

    // get field data
    Object.keys(categories).forEach(fullName => {
        const d = categories[fullName];
        if (!d) {
            console.log(`'${fullName}' not found, moving on`);
            return;
        }

        const categoryName = d.header.substring(d.header[0] === '_' ? 1 : 0, d.header.indexOf('.'));
        const itemName = d.header.substring(d.header.indexOf('.') + 1);
        let fields: { [k: string]: Column };
        if (categoryName in tables) {
            fields = tables[categoryName].columns;
            tables[categoryName].key.add(itemName);
        } else if (categoryName.toLowerCase() in tables) {
            // take case from category name in 'field' data as it is better if data is from cif dictionaries
            tables[categoryName] = tables[categoryName.toLowerCase()];
            fields = tables[categoryName].columns;
        } else {
            console.log(`category '${categoryName}' has no metadata`);
            fields = {};
            tables[categoryName] = {
                description: '',
                key: new Set(),
                columns: fields
            };
        }

        const itemAliases = getAliases(d, imports, ctx);
        if (itemAliases) aliases[`${categoryName}.${itemName}`] = itemAliases;

        const description = getDescription(d, imports, ctx) || '';

        // need to use regex to check for matrix or vector items
        // as sub_category assignment is missing for some entries
        const subCategory = getSubCategory(d, imports, ctx);
        if (subCategory === 'cartesian_coordinate' || subCategory === 'fractional_coordinate') {
            fields[itemName] = CoordCol(description);
        } else if (FORCE_INT_FIELDS.includes(d.header)) {
            fields[itemName] = IntCol(description);
            console.log(`forcing int: ${d.header}`);
        } else if (FORCE_MATRIX_FIELDS.includes(d.header)) {
            fields[itemName] = FloatCol(description);
            fields[FORCE_MATRIX_FIELDS_MAP[d.header]] = MatrixCol(3, 3, description);
            console.log(`forcing matrix: ${d.header}`);
        } else if (subCategory === 'matrix') {
            fields[itemName.replace(reMatrixField, '')] = MatrixCol(3, 3, description);
        } else if (subCategory === 'vector') {
            fields[itemName.replace(reVectorField, '')] = VectorCol(3, description);
        } else {
            if (itemName.match(reMatrixField)) {
                fields[itemName.replace(reMatrixField, '')] = MatrixCol(3, 3, description);
                console.log(`${d.header} should have 'matrix' _item_sub_category.id`);
            } else if (itemName.match(reVectorField)) {
                fields[itemName.replace(reVectorField, '')] = VectorCol(3, description);
                console.log(`${d.header} should have 'vector' _item_sub_category.id`);
            } else {
                const code = getCode(d, imports, ctx);
                if (code) {
                    let fieldType = getFieldType(code[0], description, code[1], code[2]);
                    if (fieldType.type === 'str') {
                        if (COMMA_SEPARATED_LIST_FIELDS.includes(d.header)) {
                            fieldType = ListCol('str', ',', description);
                            console.log(`forcing comma separated: ${d.header}`);
                        } else if (SPACE_SEPARATED_LIST_FIELDS.includes(d.header)) {
                            fieldType = ListCol('str', ' ', description);
                            console.log(`forcing space separated: ${d.header}`);
                        } else if (SEMICOLON_SEPARATED_LIST_FIELDS.includes(d.header)) {
                            fieldType = ListCol('str', ';', description);
                            console.log(`forcing space separated: ${d.header}`);
                        }
                    }
                    if (d.header in EXTRA_ENUM_VALUES) {
                        if (fieldType.type === 'enum') {
                            fieldType.values.push(...EXTRA_ENUM_VALUES[d.header]);
                        } else {
                            console.warn(`expected enum: ${d.header}`);
                        }
                    }
                    fields[itemName] = fieldType;
                } else {
                    fields[itemName] = StrCol(description);
                    // console.log(`could not determine code for '${d.header}'`)
                }
            }
        }
    });

    return { tables, aliases };
}