import Alpine from './vendor/alpine.js';
import {render, styles, resolveFont} from './renderer.js';
import {translations} from './translations.js';
import {setupPWA} from './pwa.js';

function savePreference(key, value) {
    try { localStorage.setItem(`ascii-pwa-${key}`, value); } catch { /* Storage may be disabled. */ }
}

function copyText(value) {
    const field = document.createElement('textarea');
    const focused = document.activeElement;
    field.value = value;
    field.readOnly = true;
    field.style.cssText = 'position:fixed;left:-9999px;top:0;font-size:16px';
    document.body.append(field);
    try {
        field.focus({preventScroll: true});
        field.select();
        field.setSelectionRange(0, field.value.length);
        if (!document.execCommand('copy')) throw new Error('Copy failed');
    } finally {
        field.remove();
        focused?.focus({preventScroll: true});
    }
}

Alpine.data('asciiApp', () => {
    let drawVersion = 0;
    let drawTimer;
    let pwa;

    return {
        styles,
        text: 'hello world',
        font: 'Standard',
        ascii: '',
        busy: true,
        statusKey: '',
        language: document.documentElement.lang,
        theme: document.documentElement.dataset.theme,
        installAvailable: false,
        updateAvailable: false,
        installed: false,

        get nextFont() {
            return styles[(styles.indexOf(this.font) + 1) % styles.length];
        },
        get canCopy() {
            return !this.busy && !!this.ascii.trim();
        },
        t(key) {
            return translations[this.language][key];
        },
        init() {
            try {
                const saved = localStorage.getItem('ascii-pwa-font');
                if (saved) this.font = resolveFont(saved);
            } catch { /* Use the default when saved preferences are unavailable. */ }
            const params = new URL(window.location.href).searchParams;
            if (params.has('text')) this.text = params.get('text').slice(0, 500);
            if (params.has('font')) this.font = resolveFont(params.get('font'));
            savePreference('font', this.font);

            this.$watch('text', () => this.scheduleDraw());
            this.$watch('font', () => {
                savePreference('font', this.font);
                this.draw();
            });
            this.$watch('language', () => {
                document.documentElement.lang = this.language;
                savePreference('language', this.language);
            });
            this.$watch('theme', () => {
                document.documentElement.dataset.theme = this.theme;
                savePreference('theme', this.theme);
            });
            pwa = setupPWA({
                installAvailable: value => { this.installAvailable = value; },
                updateAvailable: value => { this.updateAvailable = value; },
                installed: value => { this.installed = value; },
                failed: () => { this.statusKey = 'offlineFailed'; },
            });
            this.draw();
        },
        destroy() {
            clearTimeout(drawTimer);
            ++drawVersion;
            pwa?.destroy();
        },
        scheduleDraw() {
            clearTimeout(drawTimer);
            ++drawVersion;
            this.busy = true;
            drawTimer = setTimeout(() => this.draw(), 150);
        },
        async draw() {
            clearTimeout(drawTimer);
            const version = ++drawVersion;
            this.busy = true;
            try {
                const result = await render(this.text, this.font);
                if (version !== drawVersion) return;
                this.ascii = result;
                this.statusKey = '';
            } catch {
                if (version !== drawVersion) return;
                this.ascii = '';
                this.statusKey = 'renderFailed';
            } finally {
                if (version === drawVersion) this.busy = false;
            }
        },
        cycleFont(direction) {
            this.font = styles[(styles.indexOf(this.font) + direction + styles.length) % styles.length];
        },
        copy() {
            try {
                copyText(this.ascii);
                this.statusKey = 'copied';
            } catch {
                const range = document.createRange();
                range.selectNodeContents(this.$refs.output);
                window.getSelection().removeAllRanges();
                window.getSelection().addRange(range);
                this.statusKey = 'copyFailed';
            }
        },
        download() {
            const url = URL.createObjectURL(new Blob([this.ascii + '\n'], {type: 'text/plain;charset=utf-8'}));
            const link = document.createElement('a');
            link.href = url;
            link.download = 'ascii-art.txt';
            document.body.append(link);
            link.click();
            link.remove();
            setTimeout(() => URL.revokeObjectURL(url), 1000);
            this.statusKey = 'downloaded';
        },
        share() {
            const url = new URL('./', window.location.href);
            url.searchParams.set('text', this.text);
            url.searchParams.set('font', this.font);
            try {
                copyText(url.href);
                this.statusKey = 'linkCopied';
            } catch {
                window.history.replaceState(null, '', url);
                this.statusKey = 'linkFailed';
            }
        },
        install() { return pwa.install(); },
        update() { pwa.update(); },
    };
});

Alpine.start();