import { Element } from '@angular/compiler';
import { Rule, SchematicContext, Tree } from '@angular-devkit/schematics';
import { UpdateChanges } from '../common/UpdateChanges';
import { FileChange, getAttribute, findElementNodes, getSourceOffset, hasAttribute, parseFile } from '../common/util';
import { nativeImport } from '../common/import-helper.js';
import { Options } from '../../schematics/interfaces/options';

const version = '12.0.0';

export default (options: Options): Rule =>
    async (host: Tree, context: SchematicContext) => {
        context.logger.info(
            `Applying migration for Ignite UI for Angular to version ${version}`
        );

        const { HtmlParser } = await nativeImport('@angular/compiler') as typeof import('@angular/compiler');

        // eslint-disable-next-line max-len
        const UPDATE_NOTE = `<!--NOTE: This component has been updated by Infragistics migration: v${version}\nPlease check your template whether all bindings/event handlers are correct.-->\n`;

        const COMPONENTS = [
            {
                component: 'igx-bottom-nav',
                tags: ['igx-bottom-nav-item', 'igx-tab-panel', 'igx-tab'],
                tabItem: 'igx-bottom-nav-item',
                headerItem: 'igx-bottom-nav-header',
                panelItem: 'igx-bottom-nav-content',
                iconDirective: 'igxBottomNavHeaderIcon',
                labelDirective: 'igxBottomNavHeaderLabel'
            },
            {
                component: 'igx-tabs',
                tags: ['igx-tabs-group', 'igx-tab-item'],
                tabItem: 'igx-tab-item',
                headerItem: 'igx-tab-header',
                panelItem: 'igx-tab-content',
                iconDirective: 'igxTabHeaderIcon',
                labelDirective: 'igxTabHeaderLabel'
            }
        ];

        const EDITOR_COMPONENTS = [{
            COMPONENT: 'igx-date-picker',
            TEMPLATE_DIRECTIVE: 'igxDatePickerTemplate',
            TEMPLATE_WARN_MSG:
                `\n<!-- igxDatePickerTemplate has been removed.
Label, prefix, suffix and hint can now be projected directly.
See https://www.infragistics.com/products/ignite-ui-angular/angular/components/date-picker -->\n`
        }, {
            COMPONENT: 'igx-time-picker',
            TEMPLATE_DIRECTIVE: 'igxTimePickerTemplate',
            TEMPLATE_WARN_MSG:
                `\n<!-- igxTimePickerTemplate has been removed.
Label, prefix, suffix and hint can now be projected directly.
See https://www.infragistics.com/products/ignite-ui-angular/angular/components/time-picker -->\n`
        }];
        const EDITORS_MODE = ['[mode]', 'mode'];
        const EDITORS_LABEL = ['[label]', 'label'];
        const EDITORS_LABEL_VISIBILITY = ['[labelVisibility]', 'labelVisibility'];

        const update = new UpdateChanges(__dirname, host, context);
        const changes = new Map<string, FileChange[]>();
        const htmlFiles = update.templateFiles;
        const sassFiles = update.sassFiles;
        const _tsFiles = update.tsFiles;
        let applyComment = false;

        const applyChanges = () => {
            for (const [path, change] of changes.entries()) {
                let buffer = host.read(path).toString();

                change.sort((c, c1) => c.position - c1.position)
                    .reverse()
                    .forEach(c => buffer = c.apply(buffer));

                host.overwrite(path, buffer);
                applyComment = true;
            }
        };

        const addChange = (path: string, change: FileChange) => {
            if (changes.has(path)) {
                changes.get(path).push(change);
            } else {
                changes.set(path, [change]);
            }
        };

        const isEmptyOrSpaces = (str) => str === null || str === '' || str === '\n' || str === '\r\n' || str.match(/^[\r\n\t]* *$/) !== null;

        // Replace the tabsType input with tabsAligment
        for (const path of htmlFiles) {
            findElementNodes(parseFile(new HtmlParser(), host, path), 'igx-tabs')
                .forEach(node => {
                    if (hasAttribute(node as Element, 'type')) {
                        const { startTag, file } = getSourceOffset(node as Element);
                        const tabsType = getAttribute(node as Element, 'type')[0];
                        let alignment;
                        if (tabsType.value.toLowerCase() === 'fixed') {
                            alignment = 'justify';
                        } else if (tabsType.value.toLowerCase() === 'contentfit') {
                            alignment = 'start';
                        }
                        const tabAlignment = alignment ? ` tabAlignment="${alignment}"` : '';
                        addChange(file.url, new FileChange(startTag.end - 1, tabAlignment));
                    }
                });
        }
        applyChanges();
        changes.clear();

        for (const comp of COMPONENTS) {
            for (const path of htmlFiles) {
                // Replace the <ng-template igxTab> if any with <igx-tab-item>
                findElementNodes(parseFile(new HtmlParser(), host, path), comp.tags)
                    .map(tab => findElementNodes([tab], 'ng-template'))
                    .reduce((prev, curr) => prev.concat(curr), [])
                    .filter(template => hasAttribute(template as Element, 'igxTab'))
                    .forEach(node => {
                        const { startTag, endTag, file } = getSourceOffset(node as Element);
                        const content = file.content.substring(startTag.end, endTag.start);
                        const textToReplace = file.content.substring(startTag.start, endTag.end);
                        const tabPanel = `<${comp.headerItem}>${content}</${comp.headerItem}>`;
                        addChange(file.url, new FileChange(startTag.start, tabPanel, textToReplace, 'replace'));
                    });

                applyChanges();
                changes.clear();

                // Convert label and icon to igx-tab-header children ->
                // <igx-icon igxTabHeaderIcon> and <span igxTabHeaderLabel>
                findElementNodes(parseFile(new HtmlParser(), host, path), comp.tags).
                    map(node => getSourceOffset(node as Element)).
                    forEach(offset => {
                        const { startTag, file, node } = offset;
                        // Label content
                        let labelText = '';
                        if (hasAttribute(node, 'label')) {
                            const labelAttr = getAttribute(node, 'label')[0];
                            labelText = `\n<span ${comp.labelDirective}>${labelAttr.value}</span>`;
                        }
                        // Icon content
                        let iconText = '';
                        if (hasAttribute(node, 'icon')) {
                            const iconAttr = getAttribute(node, 'icon')[0];
                            iconText = `\n<igx-icon ${comp.iconDirective}>${iconAttr.value}</igx-icon>`;
                        }
                        // RouterLink
                        let routerLinkText = '';
                        if (hasAttribute(node, 'routerLink')) {
                            const routerLink = getAttribute(node, 'routerLink')[0];
                            routerLinkText = ` ${routerLink.name}="${routerLink.value}"`;
                        }

                        let classText = '';
                        if ((node.name === 'igx-tab-item' || node.name === 'igx-tab') && hasAttribute(node, 'class')) {
                            const classAttr = getAttribute(node, 'class')[0].value;
                            classText = !isEmptyOrSpaces(classAttr) ? ` class="${classAttr}"` : '';
                        }

                        if (iconText || labelText || routerLinkText) {
                            // Get igx-tab-header if it's present
                            const headerNode = findElementNodes([offset.node], comp.headerItem)
                                .map(hNode => getSourceOffset(hNode as Element));

                            if (headerNode && headerNode.length > 0) {
                                addChange(file.url, new FileChange(headerNode[0].startTag.end - 1, `${routerLinkText}${classText}`));
                            } else {
                                // eslint-disable-next-line max-len
                                const tabHeader = `\n<${comp.headerItem}${routerLinkText}${classText}>${iconText}${labelText}\n</${comp.headerItem}>`;
                                addChange(file.url, new FileChange(startTag.end, tabHeader));
                            }
                        }
                    });

                applyChanges();
                changes.clear();

                // Grab the content between <igx-tabs-group> and create a <igx-tab-content>
                // Also migrate class from igx-tabs-group to igx-tab-content, if any
                findElementNodes(parseFile(new HtmlParser(), host, path), comp.tags)
                    .map(node => getSourceOffset(node as Element))
                    .forEach(offset => {
                        const tabHeader = offset.node.children.find(c => (c as Element).name === comp.headerItem);
                        let classAttrText = '';
                        if (offset.node.name === 'igx-tab-panel' || offset.node.name === 'igx-tabs-group') {
                            const classAttr = hasAttribute(offset.node, 'class') ? getAttribute(offset.node, 'class')[0].value : '';
                            classAttrText = !isEmptyOrSpaces(classAttr) ? ` class="${classAttr}"` : '';
                        }

                        if (tabHeader) {
                            const content = offset.file.content.substring(tabHeader.sourceSpan.end.offset, offset.endTag.start);
                            // Since igx-tab-item tag is common for old and new igx-tabs
                            // Check whether igx-tab-content is already present!
                            const tabContentTag = new RegExp(String.raw`${comp.panelItem}`);
                            const hasTabContent = content.match(tabContentTag);

                            if (!hasTabContent && !isEmptyOrSpaces(content)) {
                                const tabPanel = `\n<${comp.panelItem}${classAttrText}>${content}</${comp.panelItem}>\n`;
                                addChange(offset.file.url, new FileChange(tabHeader.sourceSpan.end.offset, tabPanel, content, 'replace'));
                            }
                        }
                    });

                applyChanges();
                changes.clear();

                // Insert a comment indicating the change/replacement
                if (applyComment) {
                    findElementNodes(parseFile(new HtmlParser(), host, path), comp.component).
                        map(node => getSourceOffset(node as Element)).
                        forEach(offset => {
                            const { startTag, file } = offset;
                            const commentText = UPDATE_NOTE;
                            addChange(file.url, new FileChange(startTag.start, commentText));
                        });

                    applyChanges();
                    changes.clear();
                }
            }

            for (const sassPath of sassFiles) {
                const origContent = host.read(sassPath).toString();
                let newContent = origContent;
                let changed = false;
                for (const item of comp.tags) {
                    const searchText = new RegExp(String.raw`${item}(?=[\s])`);
                    let replaceText = '';
                    if (comp.component === 'igx-tabs') {
                        if (item === 'igx-tab-item') {
                            replaceText = comp.headerItem;
                        } else if (item === 'igx-tabs-group') {
                            replaceText = comp.panelItem;
                        }
                    }
                    if (comp.component === 'igx-bottom-nav') {
                        if (item === 'igx-tab') {
                            replaceText = comp.headerItem;
                        } else if (item === 'igx-tab-panel') {
                            replaceText = comp.panelItem;
                        }
                    }

                    if (searchText.test(origContent)) {
                        changed = true;
                        newContent = newContent.replace(searchText, replaceText);
                    }
                }
                if (changed) {
                    host.overwrite(sassPath, newContent);
                }
            }
        }

        // igxDatePicker & igxTimePicker migrations
        for (const comp of EDITOR_COMPONENTS) {
            for (const path of htmlFiles) {

                // DatePicker and TimePicker don't support templates anymore.
                // That is why migrations inserts a comment to notify the developer to remove the templates.
                findElementNodes(parseFile(new HtmlParser(), host, path), comp.COMPONENT)
                    .map(editor => findElementNodes([editor], 'ng-template'))
                    .reduce((prev, curr) => prev.concat(curr), [])
                    .filter(template => hasAttribute(template as Element, comp.TEMPLATE_DIRECTIVE))
                    .map(node => getSourceOffset(node as Element))
                    .forEach(offset => {
                        const { startTag, file } = offset;
                        addChange(file.url, new FileChange(startTag.start, comp.TEMPLATE_WARN_MSG));
                    });

                // DatePicker and TimePicker default mode is changed to dropdown.
                // 1. That is why any occurrence of drop down mode is removed and
                // 2. dialog mode is added for those that didn't explicitly set the mode prop.

                // 1. Remove dropdown mode
                findElementNodes(parseFile(new HtmlParser(), host, path), comp.COMPONENT)
                    .filter(template => hasAttribute(template as Element, EDITORS_MODE))
                    .map(node => getSourceOffset(node as Element))
                    .forEach(offset => {
                        const { file } = offset;
                        getAttribute(offset.node as Element, EDITORS_MODE).forEach(attr => {
                            const { sourceSpan, value } = attr;
                            if (value.replace(/'/g, '').replace(/"/g, '') === 'dropdown') {
                                const attrKeyValue = file.content.substring(sourceSpan.start.offset, sourceSpan.end.offset);
                                addChange(file.url, new FileChange(sourceSpan.start.offset, '', attrKeyValue, 'replace'));
                            }
                        });
                    });

                // 2. Insert dialog mode
                findElementNodes(parseFile(new HtmlParser(), host, path), comp.COMPONENT)
                    .filter(template => !hasAttribute(template as Element, EDITORS_MODE))
                    .map(node => getSourceOffset(node as Element))
                    .forEach(offset => {
                        const { startTag, file } = offset;
                        addChange(file.url, new FileChange(startTag.end - 1, ' mode="dialog"'));
                    });


                // Remove label property and project it as <label igxLabel></label>
                // Check also labelVisibility value.
                findElementNodes(parseFile(new HtmlParser(), host, path), comp.COMPONENT)
                    .filter(template => hasAttribute(template as Element, EDITORS_LABEL))
                    .map(node => getSourceOffset(node as Element))
                    .forEach(offset => {
                        const { startTag, file } = offset;
                        let visibilityValue: string | boolean = true;
                        if (hasAttribute(offset.node as Element, EDITORS_LABEL_VISIBILITY)) {
                            const visibility = getAttribute(offset.node as Element, EDITORS_LABEL_VISIBILITY);
                            visibilityValue = visibility[0].value;
                        }

                        getAttribute(offset.node as Element, EDITORS_LABEL).forEach(attr => {
                            const { sourceSpan, name, value } = attr;
                            const attrKeyValue = file.content.substring(sourceSpan.start.offset, sourceSpan.end.offset);
                            let label;
                            const ngIF = (typeof visibilityValue === 'boolean') ? `` : ` *ngIf="${visibilityValue}"`;
                            if (name.startsWith('[')) {
                                label = `\n<label igxLabel${ngIF}>{{${value}}}</label>`;
                            } else {
                                label = `\n<label igxLabel${ngIF}>${value}</label>`;
                            }
                            addChange(file.url, new FileChange(sourceSpan.start.offset, '', attrKeyValue, 'replace'));
                            addChange(file.url, new FileChange(startTag.end, label));
                        });
                    });

                // If label and labelVisibility are not set this means that we should project default labels: "Date" & "Time"
                findElementNodes(parseFile(new HtmlParser(), host, path), comp.COMPONENT)
                    .filter(template => !hasAttribute(template as Element, EDITORS_LABEL) &&
                        !hasAttribute(template as Element, EDITORS_LABEL_VISIBILITY))
                    .map(node => getSourceOffset(node as Element))
                    .forEach(offset => {
                        if (findElementNodes([offset.node], 'label').length === 0) {
                            const { startTag, file } = offset;
                            addChange(file.url,
                                new FileChange(startTag.end, `\n<label igxLabel>${comp.COMPONENT === 'igx-date-picker' ? 'Date' : 'Time'}</label>`));
                        }
                    });

                applyChanges();
                changes.clear();
            }
        }

        // input group disabled property
        const INPUT_GROUP_CHANGES = {
            GROUP_TAG: 'igx-input-group',
            ATTRIBUTES: ['[disabled]', 'disabled'],
            INPUT_TAG: ['input', 'textarea'],
            DIRECTIVE: 'igxInput'
        };

        for (const path of htmlFiles) {
            const inputGroups = findElementNodes(parseFile(new HtmlParser(), host, path), INPUT_GROUP_CHANGES.GROUP_TAG);
            inputGroups.forEach((el) => {
                const parentEl = (el as Element);
                if (hasAttribute(parentEl, INPUT_GROUP_CHANGES.ATTRIBUTES)) {
                    const inputChildren = findElementNodes([el], INPUT_GROUP_CHANGES.INPUT_TAG)
                        .reduce((prev, curr) => prev.concat(curr), [])
                        .filter(template => hasAttribute(template as Element, INPUT_GROUP_CHANGES.DIRECTIVE));
                    INPUT_GROUP_CHANGES.ATTRIBUTES.forEach((a: string) => {
                        const attr = getAttribute(parentEl, a)[0];
                        if (attr) {
                            inputChildren.forEach((node: Element) => {
                                if (!hasAttribute(node, INPUT_GROUP_CHANGES.ATTRIBUTES)) {
                                    const { startTag, file } = getSourceOffset(node as Element);
                                    // input is self-closing, so the element === startTag
                                    const repTxt = file.content.substring(startTag.start, startTag.end);
                                    const matches = repTxt.match(/\/?>/g);
                                    // should always be only 1 match
                                    const lastIndex = repTxt.indexOf(matches[0]);
                                    let property = `${attr.name}`;
                                    if (attr.name === INPUT_GROUP_CHANGES.ATTRIBUTES[0] || attr.value) {
                                        property += `="${attr.value}"`;
                                    }
                                    const addedAttr =
                                        `${repTxt.substring(0, lastIndex)} ${property}${repTxt.substring(lastIndex)}`;
                                    addChange(file.url, new FileChange(startTag.start, addedAttr, repTxt, 'replace'));
                                }
                            });
                        }
                    });
                }
            });
            applyChanges();
            changes.clear();
        }

        // Apply all selector and input changes
        update.shouldInvokeLS = options['shouldInvokeLS'];
        update.applyChanges();

    };