/*
 * Copyright (C) 2016-2020  Yomichan Authors
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

/* global
 * JsonSchemaValidator
 */

class OptionsUtil {
    constructor() {
        this._schemaValidator = new JsonSchemaValidator();
        this._optionsSchema = null;
    }

    async prepare() {
        this._optionsSchema = await this._fetchAsset('/bg/data/options-schema.json', true);
    }

    async update(options) {
        // Invalid options
        if (!isObject(options)) {
            options = {};
        }

        // Check for legacy options
        let defaultProfileOptions = {};
        if (!Array.isArray(options.profiles)) {
            defaultProfileOptions = options;
            options = {};
        }

        // Ensure profiles is an array
        if (!Array.isArray(options.profiles)) {
            options.profiles = [];
        }

        // Remove invalid profiles
        const profiles = options.profiles;
        for (let i = profiles.length - 1; i >= 0; --i) {
            if (!isObject(profiles[i])) {
                profiles.splice(i, 1);
            }
        }

        // Require at least one profile
        if (profiles.length === 0) {
            profiles.push({
                name: 'Default',
                options: defaultProfileOptions,
                conditionGroups: []
            });
        }

        // Ensure profileCurrent is valid
        const profileCurrent = options.profileCurrent;
        if (!(
            typeof profileCurrent === 'number' &&
            Number.isFinite(profileCurrent) &&
            Math.floor(profileCurrent) === profileCurrent &&
            profileCurrent >= 0 &&
            profileCurrent < profiles.length
        )) {
            options.profileCurrent = 0;
        }

        // Version
        if (typeof options.version !== 'number') {
            options.version = 0;
        }

        // Generic updates
        return await this._applyUpdates(options, this._getVersionUpdates());
    }

    async load() {
        let options;
        try {
            const optionsStr = await new Promise((resolve, reject) => {
                chrome.storage.local.get(['options'], (store) => {
                    const error = chrome.runtime.lastError;
                    if (error) {
                        reject(new Error(error.message));
                    } else {
                        resolve(store.options);
                    }
                });
            });
            options = JSON.parse(optionsStr);
        } catch (e) {
            // NOP
        }

        if (typeof options !== 'undefined') {
            options = await this.update(options);
        }

        options = this._schemaValidator.getValidValueOrDefault(this._optionsSchema, options);

        return options;
    }

    save(options) {
        return new Promise((resolve, reject) => {
            chrome.storage.local.set({options: JSON.stringify(options)}, () => {
                const error = chrome.runtime.lastError;
                if (error) {
                    reject(new Error(error.message));
                } else {
                    resolve();
                }
            });
        });
    }

    getDefault() {
        return this._schemaValidator.getValidValueOrDefault(this._optionsSchema);
    }

    createValidatingProxy(options) {
        return this._schemaValidator.createProxy(options, this._optionsSchema);
    }

    validate(options) {
        return this._schemaValidator.validate(options, this._optionsSchema);
    }

    // Legacy profile updating

    _legacyProfileUpdateGetUpdates() {
        return [
            null,
            null,
            null,
            null,
            (options) => {
                options.general.audioSource = options.general.audioPlayback ? 'jpod101' : 'disabled';
            },
            (options) => {
                options.general.showGuide = false;
            },
            (options) => {
                options.scanning.modifier = options.scanning.requireShift ? 'shift' : 'none';
            },
            (options) => {
                options.general.resultOutputMode = options.general.groupResults ? 'group' : 'split';
                options.anki.fieldTemplates = null;
            },
            (options) => {
                if (this._getStringHashCode(options.anki.fieldTemplates) === 1285806040) {
                    options.anki.fieldTemplates = null;
                }
            },
            (options) => {
                if (this._getStringHashCode(options.anki.fieldTemplates) === -250091611) {
                    options.anki.fieldTemplates = null;
                }
            },
            (options) => {
                const oldAudioSource = options.general.audioSource;
                const disabled = oldAudioSource === 'disabled';
                options.audio.enabled = !disabled;
                options.audio.volume = options.general.audioVolume;
                options.audio.autoPlay = options.general.autoPlayAudio;
                options.audio.sources = [disabled ? 'jpod101' : oldAudioSource];

                delete options.general.audioSource;
                delete options.general.audioVolume;
                delete options.general.autoPlayAudio;
            },
            (options) => {
                // Version 12 changes:
                //  The preferred default value of options.anki.fieldTemplates has been changed to null.
                if (this._getStringHashCode(options.anki.fieldTemplates) === 1444379824) {
                    options.anki.fieldTemplates = null;
                }
            },
            (options) => {
                // Version 13 changes:
                //  Default anki field tempaltes updated to include {document-title}.
                let fieldTemplates = options.anki.fieldTemplates;
                if (typeof fieldTemplates === 'string') {
                    fieldTemplates += '\n\n{{#*inline "document-title"}}\n    {{~context.document.title~}}\n{{/inline}}';
                    options.anki.fieldTemplates = fieldTemplates;
                }
            },
            (options) => {
                // Version 14 changes:
                //  Changed template for Anki audio and tags.
                let fieldTemplates = options.anki.fieldTemplates;
                if (typeof fieldTemplates !== 'string') { return; }

                const replacements = [
                    [
                        '{{#*inline "audio"}}{{/inline}}',
                        '{{#*inline "audio"}}\n    {{~#if definition.audioFileName~}}\n        [sound:{{definition.audioFileName}}]\n    {{~/if~}}\n{{/inline}}'
                    ],
                    [
                        '{{#*inline "tags"}}\n    {{~#each definition.definitionTags}}{{name}}{{#unless @last}}, {{/unless}}{{/each~}}\n{{/inline}}',
                        '{{#*inline "tags"}}\n    {{~#mergeTags definition group merge}}{{this}}{{/mergeTags~}}\n{{/inline}}'
                    ]
                ];

                for (const [pattern, replacement] of replacements) {
                    let replaced = false;
                    fieldTemplates = fieldTemplates.replace(new RegExp(escapeRegExp(pattern), 'g'), () => {
                        replaced = true;
                        return replacement;
                    });

                    if (!replaced) {
                        fieldTemplates += '\n\n' + replacement;
                    }
                }

                options.anki.fieldTemplates = fieldTemplates;
            }
        ];
    }

    _legacyProfileUpdateGetDefaults() {
        return {
            general: {
                enable: true,
                enableClipboardPopups: false,
                resultOutputMode: 'group',
                debugInfo: false,
                maxResults: 32,
                showAdvanced: false,
                popupDisplayMode: 'default',
                popupWidth: 400,
                popupHeight: 250,
                popupHorizontalOffset: 0,
                popupVerticalOffset: 10,
                popupHorizontalOffset2: 10,
                popupVerticalOffset2: 0,
                popupHorizontalTextPosition: 'below',
                popupVerticalTextPosition: 'before',
                popupScalingFactor: 1,
                popupScaleRelativeToPageZoom: false,
                popupScaleRelativeToVisualViewport: true,
                showGuide: true,
                compactTags: false,
                compactGlossaries: false,
                mainDictionary: '',
                popupTheme: 'default',
                popupOuterTheme: 'default',
                customPopupCss: '',
                customPopupOuterCss: '',
                enableWanakana: true,
                enableClipboardMonitor: false,
                showPitchAccentDownstepNotation: true,
                showPitchAccentPositionNotation: true,
                showPitchAccentGraph: false,
                showIframePopupsInRootFrame: false,
                useSecurePopupFrameUrl: true,
                usePopupShadowDom: true
            },

            audio: {
                enabled: true,
                sources: ['jpod101'],
                volume: 100,
                autoPlay: false,
                customSourceUrl: '',
                textToSpeechVoice: ''
            },

            scanning: {
                middleMouse: true,
                touchInputEnabled: true,
                selectText: true,
                alphanumeric: true,
                autoHideResults: false,
                delay: 20,
                length: 10,
                modifier: 'shift',
                deepDomScan: false,
                popupNestingMaxDepth: 0,
                enablePopupSearch: false,
                enableOnPopupExpressions: false,
                enableOnSearchPage: true,
                enableSearchTags: false,
                layoutAwareScan: false
            },

            translation: {
                convertHalfWidthCharacters: 'false',
                convertNumericCharacters: 'false',
                convertAlphabeticCharacters: 'false',
                convertHiraganaToKatakana: 'false',
                convertKatakanaToHiragana: 'variant',
                collapseEmphaticSequences: 'false'
            },

            dictionaries: {},

            parsing: {
                enableScanningParser: true,
                enableMecabParser: false,
                selectedParser: null,
                termSpacing: true,
                readingMode: 'hiragana'
            },

            anki: {
                enable: false,
                server: 'http://127.0.0.1:8765',
                tags: ['yomichan'],
                sentenceExt: 200,
                screenshot: {format: 'png', quality: 92},
                terms: {deck: '', model: '', fields: {}},
                kanji: {deck: '', model: '', fields: {}},
                duplicateScope: 'collection',
                fieldTemplates: null
            }
        };
    }

    _legacyProfileUpdateAssignDefaults(options) {
        const defaults = this._legacyProfileUpdateGetDefaults();

        const combine = (target, source) => {
            for (const key in source) {
                if (!hasOwn(target, key)) {
                    target[key] = source[key];
                }
            }
        };

        combine(options, defaults);
        combine(options.general, defaults.general);
        combine(options.scanning, defaults.scanning);
        combine(options.anki, defaults.anki);
        combine(options.anki.terms, defaults.anki.terms);
        combine(options.anki.kanji, defaults.anki.kanji);

        return options;
    }

    _legacyProfileUpdateUpdateVersion(options) {
        const updates = this._legacyProfileUpdateGetUpdates();
        this._legacyProfileUpdateAssignDefaults(options);

        const targetVersion = updates.length;
        const currentVersion = options.version;

        if (typeof currentVersion === 'number' && Number.isFinite(currentVersion)) {
            for (let i = Math.max(0, Math.floor(currentVersion)); i < targetVersion; ++i) {
                const update = updates[i];
                if (update !== null) {
                    update(options);
                }
            }
        }

        options.version = targetVersion;
        return options;
    }

    // Private

    async _addFieldTemplatesToOptions(options, additionSourceUrl) {
        let addition = null;
        for (const {options: profileOptions} of options.profiles) {
            const fieldTemplates = profileOptions.anki.fieldTemplates;
            if (fieldTemplates !== null) {
                if (addition === null) {
                    addition = await this._fetchAsset(additionSourceUrl);
                }
                profileOptions.anki.fieldTemplates = this._addFieldTemplatesBeforeEnd(fieldTemplates, addition);
            }
        }
    }

    async _addFieldTemplatesBeforeEnd(fieldTemplates, addition) {
        const pattern = /[ \t]*\{\{~?>\s*\(\s*lookup\s*\.\s*"marker"\s*\)\s*~?\}\}/;
        const newline = '\n';
        let replaced = false;
        fieldTemplates = fieldTemplates.replace(pattern, (g0) => {
            replaced = true;
            return `${addition}${newline}${g0}`;
        });
        if (!replaced) {
            fieldTemplates += newline;
            fieldTemplates += addition;
        }
        return fieldTemplates;
    }

    async _fetchAsset(url, json=false) {
        url = chrome.runtime.getURL(url);
        const response = await fetch(url, {
            method: 'GET',
            mode: 'no-cors',
            cache: 'default',
            credentials: 'omit',
            redirect: 'follow',
            referrerPolicy: 'no-referrer'
        });
        if (!response.ok) {
            throw new Error(`Failed to fetch ${url}: ${response.status}`);
        }
        return await (json ? response.json() : response.text());
    }

    _getStringHashCode(string) {
        let hashCode = 0;

        if (typeof string !== 'string') { return hashCode; }

        for (let i = 0, charCode = string.charCodeAt(i); i < string.length; charCode = string.charCodeAt(++i)) {
            hashCode = ((hashCode << 5) - hashCode) + charCode;
            hashCode |= 0;
        }

        return hashCode;
    }

    async _applyUpdates(options, updates) {
        const targetVersion = updates.length;
        let currentVersion = options.version;

        if (typeof currentVersion !== 'number' || !Number.isFinite(currentVersion)) {
            currentVersion = 0;
        }

        for (let i = Math.max(0, Math.floor(currentVersion)); i < targetVersion; ++i) {
            const {update, async} = updates[i];
            const result = update(options);
            options = (async ? await result : result);
        }

        options.version = targetVersion;
        return options;
    }

    _getVersionUpdates() {
        return [
            {
                async: false,
                update: this._updateVersion1.bind(this)
            },
            {
                async: false,
                update: this._updateVersion2.bind(this)
            },
            {
                async: true,
                update: this._updateVersion3.bind(this)
            },
            {
                async: true,
                update: this._updateVersion4.bind(this)
            }
        ];
    }

    _updateVersion1(options) {
        // Version 1 changes:
        //  Added options.global.database.prefixWildcardsSupported = false.
        options.global = {
            database: {
                prefixWildcardsSupported: false
            }
        };
        return options;
    }

    _updateVersion2(options) {
        // Version 2 changes:
        //  Legacy profile update process moved into this upgrade function.
        for (const profile of options.profiles) {
            if (!Array.isArray(profile.conditionGroups)) {
                profile.conditionGroups = [];
            }
            profile.options = this._legacyProfileUpdateUpdateVersion(profile.options);
        }
        return options;
    }

    async _updateVersion3(options) {
        // Version 3 changes:
        //  Pitch accent Anki field templates added.
        await this._addFieldTemplatesToOptions(options, '/bg/data/anki-field-templates-upgrade-v2.handlebars');
        return options;
    }

    async _updateVersion4(options) {
        // Version 4 changes:
        //  Options conditions converted to string representations.
        //  Added usePopupWindow.
        //  Updated handlebars templates to include "clipboard-image" definition.
        //  Added hideDelay.
        //  Added inputs to profileOptions.scanning.
        //  Added pointerEventsEnabled to profileOptions.scanning.
        for (const {conditionGroups} of options.profiles) {
            for (const {conditions} of conditionGroups) {
                for (const condition of conditions) {
                    const value = condition.value;
                    condition.value = (
                        Array.isArray(value) ?
                        value.join(', ') :
                        `${value}`
                    );
                }
            }
        }
        const createInputDefaultOptions = () => ({
            showAdvanced: false,
            scanOnPenHover: true,
            scanOnPenPress: true,
            scanOnPenRelease: false
        });
        for (const {options: profileOptions} of options.profiles) {
            profileOptions.general.usePopupWindow = false;
            profileOptions.scanning.hideDelay = 0;
            profileOptions.scanning.pointerEventsEnabled = false;

            const {modifier, middleMouse, touchInputEnabled} = profileOptions.scanning;
            const scanningInputs = [];
            let modifierInput = '';
            switch (modifier) {
                case 'alt':
                case 'ctrl':
                case 'shift':
                case 'meta':
                    modifierInput = modifier;
                    break;
                case 'none':
                    modifierInput = '';
                    break;
            }
            scanningInputs.push({
                include: modifierInput,
                exclude: '',
                types: {mouse: true, touch: false, pen: false},
                options: createInputDefaultOptions()
            });
            if (middleMouse) {
                scanningInputs.push({
                    include: 'mouse2',
                    exclude: '',
                    types: {mouse: true, touch: false, pen: false},
                    options: createInputDefaultOptions()
                });
            }
            if (touchInputEnabled) {
                scanningInputs.push({
                    include: '',
                    exclude: '',
                    types: {mouse: false, touch: true, pen: true},
                    options: createInputDefaultOptions()
                });
            }
            profileOptions.scanning.inputs = scanningInputs;
        }
        await this._addFieldTemplatesToOptions(options, '/bg/data/anki-field-templates-upgrade-v4.handlebars');
        return options;
    }
}