src/interactive_visualizer.py

"""
Interactive Curriculum Visualizer - FIXED VERSION
Creates CurricularAnalytics-style network graphs
"""
import streamlit as st
import networkx as nx
import plotly.graph_objects as go
import pickle
import json
from typing import Dict, List, Tuple
import numpy as np

class CurriculumVisualizer:
    """
    Creates interactive curriculum dependency graphs
    Similar to CurricularAnalytics.org
    """
    
    def __init__(self, graph: nx.DiGraph):
        self.graph = graph
        self.courses = dict(graph.nodes(data=True))
        self.positions = None
        self.layers = None
        
    def calculate_metrics(self, course_id: str) -> Dict:
        """Calculate blocking factor, delay factor, centrality"""
        
        # Blocking Factor: courses this blocks
        blocking = len(list(nx.descendants(self.graph, course_id)))
        
        # Correctly calculate the delay factor by finding the longest path
        delay = 0
        sinks = [n for n, d in self.graph.out_degree() if d == 0]
        
        max_len = 0
        for sink in sinks:
            try:
                paths = list(nx.all_simple_paths(self.graph, source=course_id, target=sink))
                if paths:
                    current_max = max(len(p) for p in paths)
                    if current_max > max_len:
                        max_len = current_max
            except (nx.NetworkXNoPath, nx.NodeNotFound):
                continue
        delay = max_len
        
        # Centrality: betweenness centrality
        centrality_dict = nx.betweenness_centrality(self.graph)
        centrality = centrality_dict.get(course_id, 0) * 100
        
        # Complexity (from your analyzer)
        complexity = self.courses[course_id].get('complexity', 0)
        
        return {
            'blocking': blocking,
            'delay': delay,
            'centrality': round(centrality, 1),
            'complexity': complexity
        }
    
    def create_hierarchical_layout(self) -> Dict:
        """Create semester-based layout like CurricularAnalytics"""
        
        # Topological sort to get course ordering
        try:
            topo_order = list(nx.topological_sort(self.graph))
        except nx.NetworkXError:
            # Has cycles, use DFS order
            topo_order = list(nx.dfs_preorder_nodes(self.graph))
        
        # Calculate depth for each node (semester level)
        depths = {}
        for node in topo_order:
            predecessors = list(self.graph.predecessors(node))
            if not predecessors:
                depths[node] = 0
            else:
                depths[node] = max(depths.get(p, 0) for p in predecessors) + 1
        
        # Group by depth (semester)
        layers = {}
        for node, depth in depths.items():
            if depth not in layers:
                layers[depth] = []
            layers[depth].append(node)
        
        # Create positions
        positions = {}
        max_width = max(len(nodes) for nodes in layers.values()) if layers else 1
        
        for depth, nodes in layers.items():
            width = len(nodes)
            spacing = 2.0 / (width + 1) if width > 0 else 1
            
            for i, node in enumerate(nodes):
                x = (i + 1) * spacing - 1  # Center around 0
                y = -depth * 2  # Vertical spacing
                positions[node] = (x, y)
        
        self.positions = positions
        self.layers = layers
        return positions
    
    def create_interactive_plot(self, highlight_path: List[str] = None) -> go.Figure:
        """Create Plotly interactive network graph"""
        
        if not self.positions:
            self.create_hierarchical_layout()
        
        # Create edge traces
        edge_traces = []
        
        for edge in self.graph.edges():
            if edge[0] not in self.positions or edge[1] not in self.positions:
                continue
            x0, y0 = self.positions[edge[0]]
            x1, y1 = self.positions[edge[1]]
            
            # Check if edge is on critical path
            is_critical = False
            if highlight_path and edge[0] in highlight_path and edge[1] in highlight_path:
                try:
                    idx0 = highlight_path.index(edge[0])
                    idx1 = highlight_path.index(edge[1])
                    is_critical = idx1 == idx0 + 1
                except ValueError:
                    is_critical = False
            
            edge_trace = go.Scatter(
                x=[x0, x1, None],
                y=[y0, y1, None],
                mode='lines',
                line=dict(
                    width=3 if is_critical else 1,
                    color='red' if is_critical else '#888'
                ),
                hoverinfo='none',
                showlegend=False
            )
            edge_traces.append(edge_trace)
        
        # Create node trace
        node_x = []
        node_y = []
        node_text = []
        node_color = []
        node_size = []
        
        for node in self.graph.nodes():
            if node not in self.positions:
                continue
            x, y = self.positions[node]
            node_x.append(x)
            node_y.append(y)
            
            # Get course info
            course_data = self.courses.get(node, {})
            metrics = self.calculate_metrics(node)
            
            # Create hover text
            hover_text = f"""
            <b>{node}: {course_data.get('name', 'Unknown')}</b><br>
            Credits: {course_data.get('credits', 4)}<br>
            <br><b>Metrics:</b><br>
            Complexity: {metrics['complexity']}<br>
            Blocking Factor: {metrics['blocking']}<br>
            Delay Factor: {metrics['delay']}<br>
            Centrality: {metrics['centrality']}<br>
            Prerequisites: {', '.join(self.graph.predecessors(node)) or 'None'}
            """
            node_text.append(hover_text)
            
            # Color by complexity
            node_color.append(metrics['complexity'])
            
            # Size by blocking factor
            node_size.append(15 + metrics['blocking'] * 2)
        
        node_trace = go.Scatter(
            x=node_x,
            y=node_y,
            mode='markers+text',
            text=[node for node in self.graph.nodes() if node in self.positions],
            textposition="top center",
            textfont=dict(size=10),
            hovertext=node_text,
            hoverinfo='text',
            marker=dict(
                showscale=True,
                colorscale='Viridis',
                size=node_size,
                color=node_color,
                colorbar=dict(
                    thickness=15,
                    title=dict(text="Complexity", side="right"), 
                    xanchor="left"
                ),
                line=dict(width=2, color='white')
            )
        )
        
        # Create figure
        fig = go.Figure(data=edge_traces + [node_trace])
        
        # FIXED: Updated layout with proper title syntax (no more titlefont_size)
        fig.update_layout(
            title=dict(
                text="Interactive Curriculum Map", 
                font=dict(size=20)
            ),
            showlegend=False,
            hovermode='closest',
            margin=dict(b=0, l=0, r=0, t=40),
            xaxis=dict(showgrid=False, zeroline=False, showticklabels=False),
            yaxis=dict(showgrid=False, zeroline=False, showticklabels=False),
            plot_bgcolor='white',
            height=800
        )
        
        return fig
    
    def find_critical_path(self) -> List[str]:
        """Find the longest path (critical path) in curriculum"""
        
        if not nx.is_directed_acyclic_graph(self.graph):
            return []
        
        # Find all paths from sources to sinks
        sources = [n for n in self.graph.nodes() if self.graph.in_degree(n) == 0]
        sinks = [n for n in self.graph.nodes() if self.graph.out_degree(n) == 0]
        
        longest_path = []
        max_length = 0
        
        for source in sources:
            for sink in sinks:
                try:
                    paths = list(nx.all_simple_paths(self.graph, source, sink))
                    for path in paths:
                        if len(path) > max_length:
                            max_length = len(path)
                            longest_path = path
                except nx.NetworkXNoPath:
                    continue
        
        return longest_path
    
    def export_to_curricular_analytics_format(self, plan: Dict) -> Dict:
        """Export plan in CurricularAnalytics JSON format"""
        
        ca_format = {
            "curriculum": {
                "name": "Generated Curriculum",
                "courses": [],
                "dependencies": []
            },
            "metrics": {}
        }
        
        # Add courses
        for course_id in self.graph.nodes():
            course_data = self.courses.get(course_id, {})
            metrics = self.calculate_metrics(course_id)
            
            ca_format["curriculum"]["courses"].append({
                "id": course_id,
                "name": course_data.get('name', ''),
                "credits": course_data.get('credits', 4),
                "complexity": metrics['complexity'],
                "blocking_factor": metrics['blocking'],
                "delay_factor": metrics['delay'],
                "centrality": metrics['centrality']
            })
        
        # Add dependencies
        for edge in self.graph.edges():
            ca_format["curriculum"]["dependencies"].append({
                "source": edge[0],
                "target": edge[1],
                "type": "prerequisite"
            })
        
        return ca_format

def run_visualizer():
    """Streamlit app for visualization"""
    
    st.set_page_config(page_title="Curriculum Visualizer", layout="wide")
    st.title("🗺️ Interactive Curriculum Visualizer")
    
    # Sidebar
    with st.sidebar:
        st.header("Controls")
        
        # File upload
        uploaded_file = st.file_uploader("Upload curriculum graph", type=['pkl'])
        
        # Display options
        show_critical = st.checkbox("Highlight Critical Path", value=True)
        show_metrics = st.checkbox("Show Metrics Panel", value=True)
        
        # Filter options
        st.subheader("Filter Courses")
        min_complexity = st.slider("Min Complexity", 0, 200, 0)
        subjects = st.multiselect("Subjects", ["CS", "DS", "MATH", "IS", "CY"])
    
    # Main content
    if uploaded_file:
        # Load graph
        graph = pickle.load(uploaded_file)
        visualizer = CurriculumVisualizer(graph)
        
        # Apply filters
        if subjects:
            nodes_to_keep = [
                n for n in graph.nodes() 
                if graph.nodes[n].get('subject') in subjects
            ]
            filtered_graph = graph.subgraph(nodes_to_keep).copy()
            visualizer = CurriculumVisualizer(filtered_graph)
        
        # Create visualization
        col1, col2 = st.columns([3, 1] if show_metrics else [1])
        
        with col1:
            # Find critical path
            critical_path = []
            if show_critical:
                critical_path = visualizer.find_critical_path()
                if critical_path:
                    st.info(f"Critical Path: {' → '.join(critical_path[:5])}...")
            
            # Create and display plot
            fig = visualizer.create_interactive_plot(critical_path)
            st.plotly_chart(fig, use_container_width=True)
        
        if show_metrics:
            with col2:
                st.subheader("📊 Curriculum Metrics")
                
                # Overall metrics
                total_courses = visualizer.graph.number_of_nodes()
                total_prereqs = visualizer.graph.number_of_edges()
                
                st.metric("Total Courses", total_courses)
                st.metric("Total Prerequisites", total_prereqs)
                if total_courses > 0:
                    st.metric("Avg Prerequisites", f"{total_prereqs/total_courses:.1f}")
                
                st.divider()
                
                # Most complex courses
                st.subheader("Most Complex Courses")
                complexities = []
                for node in visualizer.graph.nodes():
                    metrics = visualizer.calculate_metrics(node)
                    complexities.append((node, metrics['complexity']))
                
                complexities.sort(key=lambda x: x[1], reverse=True)
                
                for course, complexity in complexities[:5]:
                    name = visualizer.courses.get(course, {}).get('name', course)
                    st.write(f"**{course}**: {name}")
                    st.progress(min(complexity/200, 1.0) if complexity else 0.0)
                
                # Export button
                st.divider()
                if st.button("Export to CA Format"):
                    ca_json = visualizer.export_to_curricular_analytics_format({})
                    st.download_button(
                        "Download JSON",
                        json.dumps(ca_json, indent=2),
                        "curriculum_analytics.json",
                        "application/json"
                    )
    else:
        # Demo/instruction
        st.info("Upload a curriculum graph file to visualize")
        
        with st.expander("About this Visualizer"):
            st.write("""
            This tool creates interactive curriculum dependency graphs similar to CurricularAnalytics.org.
            
            **Features:**
            - Hierarchical layout by semester level
            - Color coding by complexity
            - Node size by blocking factor
            - Critical path highlighting
            - Interactive hover details
            - Export to CurricularAnalytics format
            
            **Metrics Calculated:**
            - **Blocking Factor**: Number of courses this prerequisite blocks
            - **Delay Factor**: Length of longest path through this course
            - **Centrality**: Importance in the curriculum network
            - **Complexity**: Combined metric from all factors
            """)

if __name__ == "__main__":
    run_visualizer()