from flask import Flask, render_template, request, redirect, url_for, session, flash, jsonify
from flask_bcrypt import Bcrypt
from pymongo import MongoClient
from bson.objectid import ObjectId
from datetime import datetime, timedelta
import os
from dotenv import load_dotenv

load_dotenv()

app = Flask(__name__)
app.config['SECRET_KEY'] = os.getenv('SECRET_KEY')

client = MongoClient(os.getenv('MONGO_URI'))
db = client.get_default_database()
bcrypt = Bcrypt(app)

# --- Helpers ---
def get_user_id():
    return session.get('user_id')

def is_logged_in():
    return 'user_id' in session

# --- Routes ---

@app.route('/')
def index():
    # If not logged in, show the landing page instead of redirecting
    if not is_logged_in():
        return render_template('landing.html')
    
    user_id = get_user_id()
    
    # Get all activities
    activities = list(db.activities.find({'user_id': user_id}))
    
    # Check for active time entry
    current_entry = db.time_entries.find_one({
        'user_id': user_id,
        'end_time': None
    })
    
    active_tasks = []
    if current_entry:
        # Get tasks associated with the active activity type
        active_activity = db.activities.find_one({'_id': current_entry['activity_id']})
        if active_activity:
            current_entry['activity_name'] = active_activity['name']
            current_entry['activity_color'] = active_activity.get('color', '#3498db')
        
        # Logic for fetching tasks:
        # 1. Fetch Session Specific Tasks (linked via time_entry_id)
        session_tasks = list(db.tasks.find({
            'user_id': user_id,
            'status': 'open',
            'time_entry_id': current_entry['_id']
        }))
        
        # 2. Fetch Contextual Tasks (linked via activity_id, no time_entry_id)
        context_criteria = {
            'user_id': user_id,
            'status': 'open',
            'activity_id': current_entry['activity_id'],
            'is_template': False,
            'time_entry_id': None
        }
        
        current_subcat = current_entry.get('subcategory')
        
        if current_subcat:
            # If active entry has subcategory: Show tasks matching that subcategory OR general tasks (no subcategory)
            context_criteria['$or'] = [
                {'subcategory': current_subcat},
                {'subcategory': {'$in': [None, '']}}
            ]
        else:
            # If active entry has NO subcategory: Show only General tasks (no subcategory assigned)
            # This hides specific subcategory tasks when just tracking the general activity
            context_criteria['subcategory'] = {'$in': [None, '']}
            
        context_tasks = list(db.tasks.find(context_criteria))
        
        active_tasks = session_tasks + context_tasks

    return render_template('dashboard.html', 
                           activities=activities, 
                           current_entry=current_entry,
                           tasks=active_tasks)

@app.route('/register', methods=['GET', 'POST'])
def register():
    if request.method == 'POST':
        username = request.form['username']
        password = request.form['password']
        
        if db.users.find_one({'username': username}):
            flash('Username already exists')
            return redirect(url_for('register'))
            
        hashed_password = bcrypt.generate_password_hash(password).decode('utf-8')
        user_id = db.users.insert_one({'username': username, 'password': hashed_password}).inserted_id
        
        # Auto login
        session['user_id'] = str(user_id)
        flash('Account created! You are now logged in.')
        return redirect(url_for('index'))
        
    return render_template('register.html')

@app.route('/login', methods=['GET', 'POST'])
def login():
    if request.method == 'POST':
        user = db.users.find_one({'username': request.form['username']})
        if user and bcrypt.check_password_hash(user['password'], request.form['password']):
            session['user_id'] = str(user['_id'])
            return redirect(url_for('index'))
        flash('Login Unsuccessful. Please check username and password')
    return render_template('login.html')

@app.route('/logout')
def logout():
    session.clear()
    return redirect(url_for('login'))

@app.route('/roadmap')
def roadmap():
    return render_template('roadmap.html')

@app.route('/add_activity', methods=['POST'])
def add_activity():
    if not is_logged_in(): return redirect(url_for('login'))
    name = request.form['name']
    color = request.form.get('color', '#3498db')
    
    activity_id = db.activities.insert_one({
        'user_id': get_user_id(),
        'name': name,
        'color': color,
        'subcategories': []
    }).inserted_id
    
    # Add optional default tasks (Revised from list input)
    tasks_str = request.form.get('tasks_list_data', '')
    if tasks_str:
        tasks = [t.strip() for t in tasks_str.split(',') if t.strip()]
        for t in tasks:
            db.tasks.insert_one({
                'user_id': get_user_id(),
                'name': t,
                'activity_id': ObjectId(activity_id),
                'is_template': True,
                'status': 'open',
                'time_entry_id': None,
                'created_at': datetime.now(),
                'comments': []
            })
            
    return redirect(url_for('index'))

@app.route('/edit_activity/<activity_id>', methods=['GET', 'POST'])
def edit_activity(activity_id):
    if not is_logged_in(): return redirect(url_for('login'))
    user_id = get_user_id()
    
    if request.method == 'POST':
        name = request.form['name']
        color = request.form.get('color', '#3498db')
        subcats_str = request.form.get('subcategories', '')
        
        # Parse comma-separated string into list
        subcategories = [s.strip() for s in subcats_str.split(',') if s.strip()]
        
        db.activities.update_one(
            {'_id': ObjectId(activity_id), 'user_id': user_id},
            {'$set': {'name': name, 'color': color, 'subcategories': subcategories}}
        )
        return redirect(url_for('index'))
        
    activity = db.activities.find_one({'_id': ObjectId(activity_id), 'user_id': user_id})
    if not activity: return "Activity not found", 404
    
    return render_template('edit_activity.html', activity=activity)

@app.route('/start_timer_bg/<activity_id>', methods=['POST'])
def start_timer_bg(activity_id):
    if not is_logged_in(): return jsonify({'error': 'auth'}), 401
    user_id = get_user_id()
    
    # Stop ANY running timer
    db.time_entries.update_many(
        {'user_id': user_id, 'end_time': None},
        {'$set': {'end_time': datetime.now()}}
    )
    
    # Start new
    start_time = datetime.now()
    new_entry_id = db.time_entries.insert_one({
        'user_id': user_id,
        'activity_id': ObjectId(activity_id),
        'start_time': start_time,
        'end_time': None,
        'note': '',
        'subcategory': ''
    }).inserted_id

    # Auto-add templates
    templates = db.tasks.find({
        'user_id': user_id,
        'activity_id': ObjectId(activity_id),
        'is_template': True
    })
    
    for t in templates:
        db.tasks.insert_one({
            'user_id': user_id,
            'name': t['name'],
            'activity_id': ObjectId(activity_id),
            'time_entry_id': new_entry_id, 
            'status': 'open',
            'is_template': False,
            'source': 'auto', # Mark as auto-generated
            'created_at': datetime.now(),
            'comments': []
        })
        
    activity = db.activities.find_one({'_id': ObjectId(activity_id)})
    
    return jsonify({
        'status': 'success', 
        'start_time': start_time.isoformat(),
        'activity_name': activity['name'],
        'activity_color': activity.get('color', '#3498db')
    })

@app.route('/update_active_entry', methods=['POST'])
def update_active_entry():
    if not is_logged_in(): return redirect(url_for('login'))
    user_id = get_user_id()
    
    note = request.form.get('note', '')
    subcategory = request.form.get('subcategory', '')
    
    db.time_entries.update_one(
        {'user_id': user_id, 'end_time': None},
        {'$set': {'note': note, 'subcategory': subcategory}}
    )
    return redirect(url_for('index'))

@app.route('/toggle_timer/<activity_id>', methods=['POST'])
def toggle_timer(activity_id):
    if not is_logged_in(): return redirect(url_for('login'))
    user_id = get_user_id()
    note = request.form.get('note', '')
    subcategory = request.form.get('subcategory', '') # Get subcategory

    # Check if this activity is currently running
    current = db.time_entries.find_one({
        'user_id': user_id, 
        'activity_id': ObjectId(activity_id),
        'end_time': None
    })

    if current:
        # Stop it
        db.time_entries.update_one(
            {'_id': current['_id']},
            {'$set': {'end_time': datetime.now()}}
        )
    else:
        # Stop ANY other running timer first
        db.time_entries.update_many(
            {'user_id': user_id, 'end_time': None},
            {'$set': {'end_time': datetime.now()}}
        )
        # Start new
        db.time_entries.insert_one({
            'user_id': user_id,
            'activity_id': ObjectId(activity_id),
            'start_time': datetime.now(),
            'end_time': None,
            'note': note,
            'subcategory': subcategory # Store it
        })
        
        # Check for Task Templates and auto-add them
        templates = db.tasks.find({
            'user_id': user_id,
            'activity_id': ObjectId(activity_id),
            'is_template': True
        })
        
        for t in templates:
            db.tasks.insert_one({
                'user_id': user_id,
                'name': t['name'],
                'activity_id': ObjectId(activity_id),
                'time_entry_id': new_entry_id, 
                'status': 'open',
                'is_template': False,
                'source': 'auto', # Mark as auto-generated
                'created_at': datetime.now(),
                'comments': []
            })
        
    return redirect(url_for('index'))

@app.route('/stop_timer', methods=['POST'])
def stop_timer():
    if not is_logged_in(): return redirect(url_for('login'))
    db.time_entries.update_many(
        {'user_id': get_user_id(), 'end_time': None},
        {'$set': {'end_time': datetime.now()}}
    )
    return redirect(url_for('index'))

@app.route('/complete_task', methods=['POST'])
def complete_task():
    if not is_logged_in(): return jsonify({'error': 'auth'}), 401
    
    user_id = get_user_id()
    task_id = request.form['task_id']
    is_checked = request.form['is_checked'] == 'true'
    
    status = 'completed' if is_checked else 'open'
    completed_at = datetime.now() if is_checked else None

    update_doc = {
        'status': status, 
        'completed_at': completed_at
    }

    # If the task is being completed, try to link it to the currently active timer
    if is_checked:
        current_entry = db.time_entries.find_one({
            'user_id': user_id,
            'end_time': None
        })
        if current_entry:
            update_doc['time_entry_id'] = current_entry['_id']

    db.tasks.update_one(
        {'_id': ObjectId(task_id), 'user_id': user_id},
        {'$set': update_doc}
    )

    return jsonify({'status': 'success'})

# --- New Task Management Routes ---

@app.route('/tasks')
def tasks():
    if not is_logged_in(): return redirect(url_for('login'))
    user_id = get_user_id()
    
    # Fetch all activities for the dropdown
    activities = list(db.activities.find({'user_id': user_id}))
    
    # Categorize tasks
    # Shows Manual Tasks (Open OR Completed). Hides "source: auto" (Session checklists)
    tasks_list = list(db.tasks.find({
        'user_id': user_id, 
        'is_template': False, 
        'source': {'$ne': 'auto'} # Show everything except explicitly auto-generated tasks
    }).sort('due_date', 1))

    # 2. Templates
    templates = list(db.tasks.find({'user_id': user_id, 'is_template': True}))
    
    # Enhance tasks with activity names
    act_map = {str(a['_id']): a for a in activities}
    for t in tasks_list + templates:
        if t.get('activity_id'):
            aid = str(t['activity_id'])
            if aid in act_map:
                t['activity_name'] = act_map[aid]['name']
                t['activity_color'] = act_map[aid].get('color', '#ccc')

    return render_template('tasks.html', tasks=tasks_list, templates=templates, activities=activities)

@app.route('/create_task', methods=['POST'])
def create_task():
    if not is_logged_in(): return redirect(url_for('login'))
    
    name = request.form['name']
    activity_id = request.form.get('activity_id')
    subcategory = request.form.get('subcategory', '') # Get subcategory
    due_date_str = request.form.get('due_date')
    is_template = 'is_template' in request.form
    
    task_doc = {
        'user_id': get_user_id(),
        'name': name,
        'status': 'open',
        'is_template': is_template,
        'source': 'manual', # Mark as manually created
        'created_at': datetime.now(),
        'comments': [],
        'subcategory': subcategory # Save subcategory
    }
    
    if activity_id:
        task_doc['activity_id'] = ObjectId(activity_id)
        
    if due_date_str:
        task_doc['due_date'] = datetime.strptime(due_date_str, '%Y-%m-%dT%H:%M')
        
    # Standard task or template doesn't belong to a specific time entry yet
    task_doc['time_entry_id'] = None
    
    db.tasks.insert_one(task_doc)
    return redirect(url_for('tasks'))

@app.route('/task/<task_id>', methods=['GET', 'POST'])
def task_detail(task_id):
    if not is_logged_in(): return redirect(url_for('login'))
    
    task = db.tasks.find_one({'_id': ObjectId(task_id), 'user_id': get_user_id()})
    if not task: return "Task not found", 404
    
    if request.method == 'POST':
        comment = request.form['comment']
        if comment:
            db.tasks.update_one(
                {'_id': ObjectId(task_id)},
                {'$push': {'comments': {
                    'text': comment, 
                    'created_at': datetime.now(),
                    'user_id': get_user_id() # In case we add teams later
                }}}
            )
            return redirect(url_for('task_detail', task_id=task_id))

    return render_template('task_detail.html', task=task)

@app.route('/logbook')
def logbook():
    if not is_logged_in(): return redirect(url_for('login'))
    user_id = get_user_id()
    
    # --- Statistics Logic ---
    time_range = request.args.get('range', '24h')
    now = datetime.now()
    
    if time_range == '24h':
        start_date = now - timedelta(hours=24)
    elif time_range == 'week':
        start_date = now - timedelta(days=7)
    elif time_range == 'month':
        start_date = now - timedelta(days=30)
    elif time_range == 'year':
        start_date = now - timedelta(days=365)
    else:
        start_date = now - timedelta(hours=24)

    # Calculate sums per activity
    pipeline_stats = [
        {'$match': {
            'user_id': user_id, 
            'end_time': {'$ne': None},
            'start_time': {'$gte': start_date}
        }},
        {'$project': {
            'activity_id': 1,
            'duration': {'$subtract': ['$end_time', '$start_time']}
        }},
        {'$group': {
            '_id': '$activity_id',
            'total_ms': {'$sum': '$duration'}
        }}
    ]
    
    stats_raw = list(db.time_entries.aggregate(pipeline_stats))
    
    chart_data = {
        'labels': [],
        'chart_values': [], # Renamed from 'values' to avoid method conflict
        'colors': []
    }
    
    total_ms_all = 0

    for s in stats_raw:
        # Sum total for all activities
        total_ms_all += s['total_ms']
        
        act = db.activities.find_one({'_id': s['_id']})
        if act:
            chart_data['labels'].append(act['name'])
            chart_data['colors'].append(act.get('color', '#ccc'))
            # Convert milliseconds to hours
            hours = s['total_ms'] / (1000 * 60 * 60)
            chart_data['chart_values'].append(round(hours, 2))
    
    # Format total time display
    if total_ms_all > 0:
        total_hours_val = total_ms_all / (1000 * 60 * 60)
        # If less than 1 hour, show minutes? Or just 0.Xh? 
        # Keeps consistency with pie chart to use hours, but let's make it look nice.
        total_time_display = f"{round(total_hours_val, 1)}h"
    else:
        total_time_display = "0h"

    # --- Existing Logbook Logic ---
    # Agrregation to join activities and tasks
    pipeline = [
        {'$match': {'user_id': user_id, 'end_time': {'$ne': None}}},
        {'$sort': {'start_time': -1}},
        {'$lookup': {
            'from': 'activities',
            'localField': 'activity_id',
            'foreignField': '_id',
            'as': 'activity'
        }},
        {'$unwind': '$activity'},
        # Join with tasks collection instead of completed_tasks
        {'$lookup': {
            'from': 'tasks', 
            'localField': '_id',
            'foreignField': 'time_entry_id',
            'as': 'tasks'
        }},
    ]
    
    log = list(db.time_entries.aggregate(pipeline))
    
    # Basic formatting
    for entry in log:
        # Filter tasks to only completed ones for display cleanly in list view
        entry['tasks'] = [t for t in entry['tasks'] if t['status'] == 'completed']
        duration = entry['end_time'] - entry['start_time']
        entry['duration_str'] = str(duration).split('.')[0] # HH:MM:SS
        
    return render_template('logbook.html', log=log, chart_data=chart_data, current_range=time_range, total_time_display=total_time_display)

@app.route('/logbook/<entry_id>', methods=['GET', 'POST'])
def log_entry_detail(entry_id):
    if not is_logged_in(): return redirect(url_for('login'))
    
    # Handle Updates and Deletion
    if request.method == 'POST':
        action = request.form.get('action')
        
        if action == 'delete':
            db.time_entries.delete_one({'_id': ObjectId(entry_id), 'user_id': get_user_id()})
            flash('Entry deleted')
            return redirect(url_for('logbook'))
            
        elif action == 'update':
            new_note = request.form.get('note')
            start_str = request.form.get('start_time')
            end_str = request.form.get('end_time')
            subcategory = request.form.get('subcategory', '')
            
            update_fields = {
                'note': new_note,
                'subcategory': subcategory
            }
            
            try:
                if start_str:
                    update_fields['start_time'] = datetime.strptime(start_str, '%Y-%m-%dT%H:%M')
                if end_str:
                    update_fields['end_time'] = datetime.strptime(end_str, '%Y-%m-%dT%H:%M')
            except ValueError:
                flash('Invalid date format')
                return redirect(url_for('log_entry_detail', entry_id=entry_id))

            db.time_entries.update_one(
                {'_id': ObjectId(entry_id), 'user_id': get_user_id()},
                {'$set': update_fields}
            )
            flash('Entry updated')
            return redirect(url_for('log_entry_detail', entry_id=entry_id))

    # Fetch Entry with Activity info
    pipeline = [
        {'$match': {'_id': ObjectId(entry_id), 'user_id': get_user_id()}},
        {'$lookup': {
            'from': 'activities',
            'localField': 'activity_id',
            'foreignField': '_id',
            'as': 'activity'
        }},
        {'$unwind': '$activity'}
    ]
    
    results = list(db.time_entries.aggregate(pipeline))
    if not results:
        return "Entry not found", 404
    
    entry = results[0]
    
    # Calculate duration
    if entry.get('end_time') and entry.get('start_time'):
        duration = entry['end_time'] - entry['start_time']
        entry['duration_str'] = str(duration).split('.')[0]
    else:
        entry['duration_str'] = "Running..."

    # Fetch ALL Tasks linked to this entry (completed or not)
    tasks = list(db.tasks.find({'time_entry_id': ObjectId(entry_id)}))
    
    return render_template('logbook_detail.html', entry=entry, tasks=tasks)

@app.route('/goals', methods=['GET', 'POST'])
def goals():
    if not is_logged_in(): return redirect(url_for('login'))
    user_id = get_user_id()
    
    # Handle creating new goal
    if request.method == 'POST':
        name = request.form['name']
        target_hours = float(request.form['target_hours'])
        frequency = request.form['frequency'] # daily, weekly, monthly, yearly
        activity_id = request.form.get('activity_id') # Required now
        subcategory = request.form.get('subcategory', '')
        
        if not activity_id:
            flash("You must select an activity for this goal.")
            return redirect(url_for('goals'))
        
        db.goals.insert_one({
            'user_id': user_id,
            'name': name,
            'target_hours': target_hours,
            'frequency': frequency,
            'activity_id': ObjectId(activity_id),
            'subcategory': subcategory,
            'created_at': datetime.now()
        })
        return redirect(url_for('goals'))
    
    # Fetch goals and calculate progress
    goals_list = list(db.goals.find({'user_id': user_id}))
    activities = list(db.activities.find({'user_id': user_id}))
    
    today = datetime.now()
    start_of_today = today.replace(hour=0, minute=0, second=0, microsecond=0)
    
    # Determine date ranges
    ranges = {
        'daily': start_of_today,
        'weekly': start_of_today - timedelta(days=today.weekday()), # Monday
        'monthly': start_of_today.replace(day=1),
        'yearly': start_of_today.replace(month=1, day=1)
    }
    
    for goal in goals_list:
        start_date = ranges.get(goal['frequency'], start_of_today)
        
        query = {
            'user_id': user_id,
            'start_time': {'$gte': start_date},
            'end_time': {'$ne': None} 
        }
        
        if goal.get('activity_id'):
            query['activity_id'] = goal['activity_id']
        
        if goal.get('subcategory'):
            query['subcategory'] = goal['subcategory']
            
        entries = list(db.time_entries.find(query))
        
        total_seconds = sum([(e['end_time'] - e['start_time']).total_seconds() for e in entries])
        current_hours = total_seconds / 3600
        
        # Display formatting: Show minutes if < 1 hour, else show hours
        if current_hours > 0 and current_hours < 1:
            minutes = int(total_seconds / 60)
            goal['display_progress'] = f"{minutes}m"
        else:
            goal['display_progress'] = f"{round(current_hours, 1)}h"
            
        goal['current_hours'] = round(current_hours, 1) # Keep purely numeric for math/sorting if needed
        goal['percent'] = min(100, int((current_hours / goal['target_hours']) * 100))
        
        # Link activity name for display
        if goal.get('activity_id'):
            act = db.activities.find_one({'_id': goal['activity_id']})
            goal['activity_name'] = act['name'] if act else 'Unknown'
            goal['activity_color'] = act['color'] if act else '#ccc'

    return render_template('goals.html', goals=goals_list, activities=activities)

@app.route('/edit_goal/<goal_id>', methods=['GET', 'POST'])
def edit_goal(goal_id):
    if not is_logged_in(): return redirect(url_for('login'))
    user_id = get_user_id()
    
    if request.method == 'POST':
        name = request.form['name']
        target_hours = float(request.form['target_hours'])
        frequency = request.form['frequency']
        activity_id = request.form.get('activity_id')
        subcategory = request.form.get('subcategory', '')
        
        db.goals.update_one(
            {'_id': ObjectId(goal_id), 'user_id': user_id},
            {'$set': {
                'name': name,
                'target_hours': target_hours,
                'frequency': frequency,
                'activity_id': ObjectId(activity_id),
                'subcategory': subcategory
            }}
        )
        return redirect(url_for('goals'))

    goal = db.goals.find_one({'_id': ObjectId(goal_id), 'user_id': user_id})
    if not goal: return "Goal not found", 404
    
    activities = list(db.activities.find({'user_id': user_id}))
    return render_template('edit_goal.html', goal=goal, activities=activities)

@app.route('/delete_goal/<goal_id>')
def delete_goal(goal_id):
    if not is_logged_in(): return redirect(url_for('login'))
    db.goals.delete_one({'_id': ObjectId(goal_id), 'user_id': get_user_id()})
    return redirect(url_for('goals'))

debug = os.getenv('DEBUG') == 'False'
host = os.getenv('HOST')
port = int(os.getenv('PORT', 80))


if __name__ == '__main__':
    app.run(debug=False, host=host, port=port)