import app from '../app.js';

const api = app.getAPI();
const logger = app.getLogger();

class CodeEditorView extends HTMLElement {
    constructor() {
        super();
        this.editor = null;
        this.file = null;
        this.previousView = null;
        this.isRendered = false;
    }

    connectedCallback() {
        logger.debug('CodeEditorView connected');
    }

    disconnectedCallback() {
        logger.debug('CodeEditorView disconnected');
        this.destroyEditor();
    }

    async setFile(file, previousView = 'files') {
        if (this.isRendered) {
            logger.warn('Editor already rendered, skipping');
            return;
        }

        this.file = file;
        this.previousView = previousView;
        this.isRendered = true;

        try {
            logger.debug('Loading file', { fileName: file.name });
            const blob = await api.downloadFile(file.id);
            const content = await blob.text();

            this.createUI(content);
            this.createEditor(content);
        } catch (error) {
            logger.error('Failed to load file', error);
            document.dispatchEvent(new CustomEvent('show-toast', {
                detail: { message: 'Failed to load file: ' + error.message, type: 'error' }
            }));
            window.history.back();
        }
    }

    createUI(content) {
        this.innerHTML = `
            <div class="code-editor-overlay">
                <div class="code-editor-header">
                    <div class="header-left">
                        <button class="button" id="back-btn">Back</button>
                        <div class="preview-info">
                            <h2 class="preview-file-name">${this.escapeHtml(this.file.name)}</h2>
                            <p class="preview-file-info">${this.formatFileSize(this.file.size)} • ${new Date(this.file.created_at).toLocaleDateString()}</p>
                        </div>
                    </div>
                    <div class="preview-actions">
                        <button class="button" id="download-btn">Download</button>
                        <button class="button button-primary" id="save-btn">Save & Close</button>
                    </div>
                </div>
                <div class="code-editor-body">
                    <textarea id="editor-textarea"></textarea>
                </div>
            </div>
        `;

        const backBtn = this.querySelector('#back-btn');
        const saveBtn = this.querySelector('#save-btn');
        const downloadBtn = this.querySelector('#download-btn');

        backBtn.addEventListener('click', () => this.close());
        saveBtn.addEventListener('click', () => this.save());
        downloadBtn.addEventListener('click', () => this.downloadFile());

        document.addEventListener('keydown', this.handleKeydown.bind(this));
    }

    createEditor(content) {
        const textarea = this.querySelector('#editor-textarea');
        if (!textarea) {
            logger.error('Textarea not found');
            return;
        }

        textarea.value = content;

        const mode = this.getMode(this.file.name);
        logger.debug('Creating CodeMirror editor', { mode, fileSize: content.length });

        this.editor = CodeMirror.fromTextArea(textarea, {
            mode: mode,
            lineNumbers: true,
            lineWrapping: true,
            indentUnit: 4,
            indentWithTabs: false,
            theme: 'default',
            readOnly: false,
            autofocus: true,
            extraKeys: {
                'Ctrl-S': () => { this.save(); return false; },
                'Cmd-S': () => { this.save(); return false; },
                'Esc': () => { this.close(); return false; }
            }
        });

        this.editor.setSize('100%', '100%');

        setTimeout(() => {
            if (this.editor) {
                this.editor.refresh();
                this.editor.focus();
                logger.debug('Editor ready and focused');
            }
        }, 100);
    }

    getMode(filename) {
        const ext = filename.split('.').pop().toLowerCase();
        const modes = {
            'js': 'javascript',
            'json': { name: 'javascript', json: true },
            'py': 'python',
            'md': 'markdown',
            'html': 'htmlmixed',
            'xml': 'xml',
            'css': 'css',
            'txt': 'text/plain',
            'log': 'text/plain',
            'sh': 'shell',
            'yaml': 'yaml',
            'yml': 'yaml'
        };
        return modes[ext] || 'text/plain';
    }

    escapeHtml(text) {
        const div = document.createElement('div');
        div.textContent = text;
        return div.innerHTML;
    }

    async downloadFile() {
        try {
            const blob = await api.downloadFile(this.file.id);
            const url = URL.createObjectURL(blob);
            const a = document.createElement('a');
            a.href = url;
            a.download = this.file.name;
            document.body.appendChild(a);
            a.click();
            window.URL.revokeObjectURL(url);
            document.body.removeChild(a);
        } catch (error) {
            console.error('Failed to download file:', error);
        }
    }

    formatFileSize(bytes) {
        const units = ['B', 'KB', 'MB', 'GB'];
        let size = bytes;
        let unitIndex = 0;
        while (size >= 1024 && unitIndex < units.length - 1) {
            size /= 1024;
            unitIndex++;
        }
        return `${size.toFixed(1)} ${units[unitIndex]}`;
    }

    handleKeydown(e) {
        if (e.key === 'Escape' && !this.editor.getOption('readOnly')) {
            this.close();
        }
    }

    async save() {
        if (!this.editor) {
            logger.warn('No editor instance');
            return;
        }

        const saveBtn = this.querySelector('#save-btn');
        if (!saveBtn) return;

        try {
            saveBtn.disabled = true;
            saveBtn.textContent = 'Saving...';

            const content = this.editor.getValue();
            logger.debug('Saving file', { fileName: this.file.name, size: content.length });

            await api.updateFile(this.file.id, content);

            logger.info('File saved successfully', { fileName: this.file.name });

            document.dispatchEvent(new CustomEvent('show-toast', {
                detail: { message: 'File saved successfully!', type: 'success' }
            }));

            setTimeout(() => {
                this.close();
            }, 500);

        } catch (error) {
            logger.error('Failed to save file', error);
            document.dispatchEvent(new CustomEvent('show-toast', {
                detail: { message: 'Failed to save: ' + error.message, type: 'error' }
            }));

            if (saveBtn) {
                saveBtn.disabled = false;
                saveBtn.textContent = 'Save & Close';
            }
        }
    }

    close() {
        logger.debug('Closing editor');
        window.history.back();
    }

    hide() {
        logger.debug('Hiding editor');
        this.destroyEditor();
        this.remove();
    }

    destroyEditor() {
        if (this.editor) {
            logger.debug('Destroying CodeMirror instance');
            try {
                this.editor.toTextArea();
            } catch (e) {
                logger.warn('Error destroying editor', e);
            }
            this.editor = null;
        }
    }
}

customElements.define('code-editor-view', CodeEditorView);
export { CodeEditorView };