// LinkSync API Client
// Handles all communication with LinkSyncServer

const API = {
    baseUrl: "",
    token: "",
    maxRetries: 3,
    retryDelay: 1000,
    timeout: 10000,

    async init() {
        const settings = await this.getSettings();
        this.baseUrl = (settings.serverUrl || "http://localhost:5000").replace(/\/+$/, "");
        this.token = settings.apiKey || "";
    },

    async getSettings() {
        return new Promise((resolve) => {
            browser.storage.local.get(
                ["linksync_server_url", "linksync_api_key"],
                (result) => resolve(result)
            );
        });
    },

    async request(method, path, body = null) {
        await this.init();

        if (!this.token) {
            throw new Error("Not authenticated. Set your API key in settings.");
        }

        let lastError;
        for (let attempt = 1; attempt <= this.maxRetries; attempt++) {
            try {
                const controller = new AbortController();
                const timeoutId = setTimeout(() => controller.abort(), this.timeout);

                const options = {
                    method,
                    headers: {
                        "Content-Type": "application/json",
                        Authorization: `Bearer ${this.token}`,
                    },
                    signal: controller.signal,
                };

                if (body && method !== "GET") {
                    options.body = JSON.stringify(body);
                }

                const response = await fetch(`${this.baseUrl}${path}`, options);
                clearTimeout(timeoutId);

                if (response.status === 401) {
                    throw new Error("Authentication failed. Check your API key.");
                }

                if (response.status === 429) {
                    const retryAfter = parseInt(response.headers.get("Retry-After"), 10) || this.retryDelay * attempt;
                    await this.delay(retryAfter);
                    continue;
                }

                if (!response.ok) {
                    const errorData = await response.json().catch(() => null);
                    throw new Error(
                        errorData?.detail || `Server error: ${response.status} ${response.statusText}`
                    );
                }

                const contentType = response.headers.get("content-type");
                if (contentType && contentType.includes("application/json")) {
                    return await response.json();
                }
                return null;
            } catch (error) {
                lastError = error;
                if (error.name === "AbortError") {
                    lastError = new Error("Request timed out");
                }
                if (attempt < this.maxRetries) {
                    await this.delay(this.retryDelay * attempt);
                }
            }
        }

        throw lastError || new Error("Request failed after retries");
    },

    async get(path) {
        return this.request("GET", path);
    },

    async post(path, body) {
        return this.request("POST", path, body);
    },

    async put(path, body) {
        return this.request("PUT", path, body);
    },

    async delete(path) {
        return this.request("DELETE", path);
    },

    async login(username, password) {
        const controller = new AbortController();
        const timeoutId = setTimeout(() => controller.abort(), this.timeout);

        const formData = new URLSearchParams();
        formData.append("username", username);
        formData.append("password", password);

        const settings = await this.getSettings();
        this.baseUrl = (settings.serverUrl || "http://localhost:5000").replace(/\/+$/, "");

        const response = await fetch(`${this.baseUrl}/api/auth/login`, {
            method: "POST",
            headers: { "Content-Type": "application/x-www-form-urlencoded" },
            body: formData.toString(),
            signal: controller.signal,
        });
        clearTimeout(timeoutId);

        if (!response.ok) {
            const error = await response.json().catch(() => null);
            throw new Error(error?.detail || "Login failed");
        }

        const data = await response.json();
        this.token = data.access_token;

        await browser.storage.local.set({ linksync_api_key: data.access_token });
        return data;
    },

    async testConnection() {
        await this.init();
        const response = await fetch(`${this.baseUrl}/health`, {
            method: "GET",
            signal: AbortSignal.timeout(this.timeout),
        });
        if (!response.ok) throw new Error(`Server returned ${response.status}`);
        return await response.json();
    },

    // Links
    async getLinks(params = {}) {
        const qs = new URLSearchParams(params).toString();
        return this.get(`/api/links/${qs ? "?" + qs : ""}`);
    },

    async createLink(data) {
        return this.post("/api/links/", data);
    },

    async updateLink(id, data) {
        return this.put(`/api/links/${id}/`, data);
    },

    async deleteLink(id) {
        return this.delete(`/api/links/${id}/`);
    },

    // Collections
    async getCollections() {
        return this.get("/api/collections/");
    },

    async createCollection(data) {
        return this.post("/api/collections/", data);
    },

    async updateCollection(id, data) {
        return this.put(`/api/collections/${id}/`, data);
    },

    async deleteCollection(id) {
        return this.delete(`/api/collections/${id}/`);
    },

    async refreshCollection(id) {
        return this.post(`/api/collections/${id}/refresh`, {});
    },

    // Queries
    async parseQuery(expression) {
        return this.post(`/api/queries/parse?expression=${encodeURIComponent(expression)}`);
    },

    async executeQuery(expression, limit = 50) {
        return this.post(
            `/api/queries/execute?expression=${encodeURIComponent(expression)}&limit=${limit}`
        );
    },

    // Sync
    async sync(config, browserBookmarks) {
        return this.post("/api/sync/", {
            mode: config.mode,
            deletions_enabled: config.deletions,
            browser_bookmarks: browserBookmarks,
        });
    },

    // Admin
    async getAdminStats() {
        return this.get("/api/admin/stats");
    },

    delay(ms) {
        return new Promise((resolve) => setTimeout(resolve, ms));
    },
};