/*
   ELYSIA MARKDOWN STUDIO v1.0 - Editor Module
   Markdown editor with toolbar actions
*/

import Utils from "./utils.js";

const Editor = {
    textarea: null,
    currentDoc: null,
    autoSaveInterval: null,
    autoSaveInProgress: false, // Prevent race conditions

    init() {
        this.textarea = document.getElementById("markdown-editor");
        this.setupEventListeners();
        this.setupToolbar();
        // Don't start auto-save yet - wait for app to be fully initialized
    },

    setupEventListeners() {
        // Input event for stats update
        this.textarea.addEventListener(
            "input",
            Utils.debounce(() => {
                this.updateStats();

                // Check if live preview is enabled
                const livePreview = Utils.storage.get("livePreview", true);
                if (livePreview && window.app?.preview) {
                    window.app.preview.update();
                }

                // Mark unsaved changes
                if (window.app) {
                    window.app.unsavedChanges = true;
                }
            }, 300)
        );

        // Drag & drop for images
        this.textarea.addEventListener("dragover", e => {
            e.preventDefault();
            this.textarea.classList.add("drag-over");
        });

        this.textarea.addEventListener("dragleave", e => {
            e.preventDefault();
            this.textarea.classList.remove("drag-over");
        });

        this.textarea.addEventListener("drop", e => {
            e.preventDefault();
            this.textarea.classList.remove("drag-over");
            this.handleImageDrop(e);
        });

        // Paste images from clipboard
        this.textarea.addEventListener("paste", e => {
            const items = e.clipboardData?.items;
            if (!items) return;

            for (const item of items) {
                if (item.type.startsWith("image/")) {
                    e.preventDefault();
                    this.handleImagePaste(item);
                    break;
                }
            }
        });

        // Keyboard shortcuts
        this.textarea.addEventListener("keydown", e => {
            if (e.ctrlKey || e.metaKey) {
                switch (e.key.toLowerCase()) {
                    case "s":
                        e.preventDefault();
                        window.app?.saveDocument();
                        break;
                    case "b":
                        e.preventDefault();
                        this.wrapSelection("**", "**");
                        break;
                    case "i":
                        e.preventDefault();
                        this.wrapSelection("*", "*");
                        break;
                }
            }
        });
    },

    setupToolbar() {
        document.querySelectorAll(".toolbar-btn").forEach(btn => {
            btn.addEventListener("click", () => {
                const action = btn.getAttribute("data-action");
                this.handleToolbarAction(action);
            });
        });
    },

    handleToolbarAction(action) {
        switch (action) {
            case "bold":
                this.wrapSelection("**", "**");
                break;
            case "italic":
                this.wrapSelection("*", "*");
                break;
            case "strikethrough":
                this.wrapSelection("~~", "~~");
                break;
            case "heading1":
                this.insertAtLineStart("# ");
                break;
            case "heading2":
                this.insertAtLineStart("## ");
                break;
            case "heading3":
                this.insertAtLineStart("### ");
                break;
            case "link":
                this.insertLink();
                break;
            case "image":
                this.insertImage();
                break;
            case "code":
                this.wrapSelection("`", "`");
                break;
            case "quote":
                this.insertAtLineStart("> ");
                break;
            case "ul":
                this.insertAtLineStart("- ");
                break;
            case "ol":
                this.insertAtLineStart("1. ");
                break;
            case "task":
                this.insertAtLineStart("- [ ] ");
                break;
            case "table":
                this.insertTable();
                break;
            case "hr":
                this.insertLine("\n---\n");
                break;
        }

        this.textarea.focus();
    },

    wrapSelection(before, after) {
        const start = this.textarea.selectionStart;
        const end = this.textarea.selectionEnd;
        const text = this.textarea.value;
        const selected = text.substring(start, end);

        const wrapped = before + (selected || "text") + after;
        this.textarea.setRangeText(wrapped, start, end, "select");

        this.textarea.dispatchEvent(new Event("input"));
    },

    insertAtLineStart(prefix) {
        const start = this.textarea.selectionStart;
        const text = this.textarea.value;

        // Find line start
        let lineStart = start;
        while (lineStart > 0 && text[lineStart - 1] !== "\n") {
            lineStart--;
        }

        this.textarea.setRangeText(prefix, lineStart, lineStart, "end");
        this.textarea.dispatchEvent(new Event("input"));
    },

    insertLine(text) {
        const start = this.textarea.selectionStart;
        this.textarea.setRangeText(text, start, start, "end");
        this.textarea.dispatchEvent(new Event("input"));
    },

    insertLink() {
        const url = prompt("Enter URL:");
        if (!url) return;

        const text = prompt("Link text (optional):") || url;
        this.wrapSelection(`[${text}](`, `)`);
    },

    insertImage() {
        const url = prompt("Enter image URL:");
        if (!url) return;

        const alt = prompt("Alt text (optional):") || "image";
        const markdown = `![${alt}](${url})`;

        const start = this.textarea.selectionStart;
        this.textarea.setRangeText(markdown, start, start, "end");
        this.textarea.dispatchEvent(new Event("input"));
    },

    insertTable() {
        const table = `\n| Header 1 | Header 2 | Header 3 |\n|----------|----------|----------|\n| Cell 1   | Cell 2   | Cell 3   |\n| Cell 4   | Cell 5   | Cell 6   |\n`;
        this.insertLine(table);
    },

    updateStats() {
        const content = this.textarea.value;

        const wordCount = Utils.countWords(content);
        const charCount = Utils.countChars(content);
        const lineCount = Utils.countLines(content);
        const readingTime = Utils.readingTime(wordCount);

        document.getElementById("word-count").textContent = `${wordCount} words`;
        document.getElementById("char-count").textContent = `${charCount} chars`;
        document.getElementById("line-count").textContent = `${lineCount} lines`;

        // Add reading time if element exists
        const readingTimeEl = document.getElementById("reading-time");
        if (readingTimeEl) {
            readingTimeEl.textContent = readingTime;
        }

        // Update current doc stats if exists
        if (this.currentDoc) {
            this.currentDoc.wordCount = wordCount;
            this.currentDoc.charCount = charCount;
        }
    },

    getContent() {
        return this.textarea.value;
    },

    setContent(content) {
        this.textarea.value = content || "";
        this.updateStats();
        window.app?.preview.update();
    },

    clear() {
        this.setContent("");
    },

    startAutoSave() {
        // Stop any existing interval
        this.stopAutoSave();

        const autoSaveEnabled = Utils.storage.get("autoSave", true);
        if (!autoSaveEnabled) return;

        // Only start if app is fully initialized
        if (!window.app) {
            console.warn("Auto-save deferred - app not initialized yet");
            return;
        }

        this.autoSaveInterval = setInterval(async () => {
            // Prevent concurrent auto-saves
            if (this.autoSaveInProgress) {
                console.log("⏭️ Skipping auto-save - already in progress");
                return;
            }

            if (window.app?.unsavedChanges && this.textarea.value) {
                try {
                    this.autoSaveInProgress = true;
                    await window.app.saveDocument(true); // Silent save
                    console.log("💾 Auto-saved");
                } catch (err) {
                    console.error("Auto-save failed:", err);
                } finally {
                    this.autoSaveInProgress = false;
                }
            }
        }, 30000); // 30 seconds

        console.log("✅ Auto-save enabled (every 30s)");
    },

    stopAutoSave() {
        if (this.autoSaveInterval) {
            clearInterval(this.autoSaveInterval);
            this.autoSaveInterval = null;
        }
    },

    // Handle image drop
    handleImageDrop(e) {
        const files = e.dataTransfer?.files;
        if (!files || files.length === 0) return;

        for (const file of files) {
            if (file.type.startsWith("image/")) {
                this.insertImageFromFile(file);
            }
        }
    },

    // Handle image paste
    handleImagePaste(item) {
        const file = item.getAsFile();
        if (file) {
            this.insertImageFromFile(file);
        }
    },

    // Insert image from file (convert to base64 data URL)
    insertImageFromFile(file) {
        const reader = new FileReader();

        reader.onload = e => {
            const dataUrl = e.target.result;
            const altText = file.name.replace(/\.[^/.]+$/, ""); // Remove extension
            const markdown = `\n![${altText}](${dataUrl})\n`;

            const start = this.textarea.selectionStart;
            this.textarea.setRangeText(markdown, start, start, "end");
            this.textarea.dispatchEvent(new Event("input"));

            Utils.toast.success(`Image "${file.name}" inserted!`);
        };

        reader.onerror = () => {
            Utils.toast.error("Failed to read image file");
        };

        reader.readAsDataURL(file);
    }
};

export default Editor;