feat: Add mobile-first frontend for training tracker

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/js/api.js

@@ -0,0 +1,139 @@
+// API Client for Training Tracker
+
+const API_BASE_URL = 'http://localhost:8080/api';
+
+class ApiClient {
+    constructor(baseUrl = API_BASE_URL) {
+        this.baseUrl = baseUrl;
+    }
+
+    async request(endpoint, options = {}) {
+        const url = `${this.baseUrl}${endpoint}`;
+        const config = {
+            headers: {
+                'Content-Type': 'application/json',
+                ...options.headers,
+            },
+            ...options,
+        };
+
+        if (config.body && typeof config.body === 'object') {
+            config.body = JSON.stringify(config.body);
+        }
+
+        try {
+            const response = await fetch(url, config);
+
+            if (response.status === 204) {
+                return null;
+            }
+
+            const data = await response.json();
+
+            if (!response.ok) {
+                throw new Error(data.error || 'API request failed');
+            }
+
+            return data;
+        } catch (error) {
+            console.error('API Error:', error);
+            throw error;
+        }
+    }
+
+    // Exercises
+    async getExercises() {
+        return this.request('/exercises');
+    }
+
+    async getExercise(id) {
+        return this.request(`/exercises/${id}`);
+    }
+
+    async createExercise(data) {
+        return this.request('/exercises', {
+            method: 'POST',
+            body: data,
+        });
+    }
+
+    async updateExercise(id, data) {
+        return this.request(`/exercises/${id}`, {
+            method: 'PUT',
+            body: data,
+        });
+    }
+
+    async deleteExercise(id) {
+        return this.request(`/exercises/${id}`, {
+            method: 'DELETE',
+        });
+    }
+
+    // Training Plans
+    async getPlans() {
+        return this.request('/plans');
+    }
+
+    async getPlan(id) {
+        return this.request(`/plans/${id}`);
+    }
+
+    async createPlan(data) {
+        return this.request('/plans', {
+            method: 'POST',
+            body: data,
+        });
+    }
+
+    async updatePlan(id, data) {
+        return this.request(`/plans/${id}`, {
+            method: 'PUT',
+            body: data,
+        });
+    }
+
+    async deletePlan(id) {
+        return this.request(`/plans/${id}`, {
+            method: 'DELETE',
+        });
+    }
+
+    // Sessions
+    async getSessions() {
+        return this.request('/sessions');
+    }
+
+    async getSession(id) {
+        return this.request(`/sessions/${id}`);
+    }
+
+    async createSession(data) {
+        return this.request('/sessions', {
+            method: 'POST',
+            body: data,
+        });
+    }
+
+    async updateSession(id, data) {
+        return this.request(`/sessions/${id}`, {
+            method: 'PUT',
+            body: data,
+        });
+    }
+
+    async deleteSession(id) {
+        return this.request(`/sessions/${id}`, {
+            method: 'DELETE',
+        });
+    }
+
+    async addSessionEntry(sessionId, data) {
+        return this.request(`/sessions/${sessionId}/entries`, {
+            method: 'POST',
+            body: data,
+        });
+    }
+}
+
+const api = new ApiClient();