import gradio as gr
import joblib
import numpy as np
import pandas as pd
from sklearn.preprocessing import StandardScaler
from fastapi import FastAPI, HTTPException
from pydantic import BaseModel
import uvicorn
import os
import requests
import json
from datetime import datetime, timedelta, timezone
from typing import Dict, List, Optional
from urllib.parse import urlparse
import time

# Create FastAPI app
app = FastAPI(title="Developer Productivity Prediction API", version="1.0.0")

# Load the trained model and scaler
model = joblib.load('dev_productivity_model.joblib')
scaler = joblib.load('scaler.joblib')

# Pydantic models
class ProductivityRequest(BaseModel):
    daily_coding_hours: float
    commits_per_day: int
    pull_requests_per_week: int
    issues_closed_per_week: int
    active_repos: int
    code_reviews_per_week: int

class ProductivityResponse(BaseModel):
    predicted_score: float
    status: str

class GitHubAnalysisRequest(BaseModel):
    repo_url: str
    github_token: str

class GitHubAnalysisResponse(BaseModel):
    repo_metrics: dict
    ml_features: dict
    predicted_score: float
    productivity_indicators: dict
    status: str

# GitHub Repository Analyzer
class RepoProductivityAnalyzer:
    def __init__(self, github_token: str):
        if not github_token or github_token == "YOUR_TOKEN_HERE":
            raise ValueError("Please provide a valid GitHub token")
        
        self.token = github_token
        self.headers = {
            'Authorization': f'token {github_token}',
            'Accept': 'application/vnd.github.v3+json'
        }
        self.days_back = 90
        self.max_retries = 3
    
    def safe_request(self, url: str, retries: int = None) -> Optional[List]:
        if retries is None:
            retries = self.max_retries
            
        for attempt in range(retries):
            try:
                response = requests.get(url, headers=self.headers, timeout=30)
                
                if response.status_code == 200:
                    return response.json()
                elif response.status_code == 403:
                    time.sleep(60)  # Rate limit
                    continue
                elif response.status_code == 404:
                    return []
                else:
                    return []
                    
            except requests.exceptions.RequestException:
                if attempt < retries - 1:
                    time.sleep(2 ** attempt)
                else:
                    return []
        return []
    
    def parse_repo_url(self, repo_url: str) -> tuple:
        try:
            parsed = urlparse(repo_url)
            path = parsed.path.strip('/').split('/')
            if len(path) < 2:
                raise ValueError("Invalid GitHub URL format")
            return path[0], path[1]
        except Exception as e:
            raise ValueError(f"Invalid repo URL: {str(e)}")
    
    def safe_parse_datetime(self, date_str: str) -> Optional[datetime]:
        if not date_str:
            return None
        try:
            dt = datetime.fromisoformat(date_str.replace('Z', '+00:00'))
            if dt.tzinfo is None:
                dt = dt.replace(tzinfo=timezone.utc)
            return dt
        except:
            return None
    
    def get_metrics(self, repo_url: str) -> Dict:
        try:
            owner, repo = self.parse_repo_url(repo_url)
        except ValueError as e:
            return {"error": str(e)}
        
        now = datetime.now(timezone.utc)
        since_dt = now - timedelta(days=self.days_back)
        since = since_dt.isoformat()
        
        metrics = {
            'repo': f"{owner}/{repo}",
            'period_days': self.days_back,
            'analyzed_at': now.isoformat(),
            'status': 'success'
        }
        
        try:
            # Check repo exists
            repo_info = self.safe_request(f"https://api.github.com/repos/{owner}/{repo}")
            if not repo_info:
                return {"error": "Repository not found or inaccessible"}
            
            # Get commits
            commits_url = f"https://api.github.com/repos/{owner}/{repo}/commits?per_page=100&since={since}"
            commits = self.safe_request(commits_url) or []
            metrics['total_commits'] = len(commits)
            
            # Get PRs
            prs_url = f"https://api.github.com/repos/{owner}/{repo}/pulls?state=all&per_page=100"
            prs = self.safe_request(prs_url) or []
            
            recent_prs = []
            for pr in prs:
                created_at = self.safe_parse_datetime(pr.get('created_at'))
                if created_at and created_at >= since_dt:
                    recent_prs.append(pr)
            
            metrics['prs_total'] = len(recent_prs)
            metrics['prs_merged'] = len([p for p in recent_prs if p.get('merged_at')])
            
            # Get issues
            issues_url = f"https://api.github.com/repos/{owner}/{repo}/issues?state=closed&per_page=100"
            issues = self.safe_request(issues_url) or []
            
            recent_issues = []
            for issue in issues:
                closed_at = self.safe_parse_datetime(issue.get('closed_at'))
                if closed_at and closed_at >= since_dt:
                    recent_issues.append(issue)
            
            metrics['issues_total'] = len(recent_issues)
            
            # Calculate rates
            metrics['commits_per_day'] = metrics['total_commits'] / max(self.days_back, 1)
            metrics['prs_per_week'] = metrics['prs_total'] / max((self.days_back / 7), 1)
            metrics['issues_per_week'] = metrics['issues_total'] / max((self.days_back / 7), 1)
            
            return metrics
            
        except Exception as e:
            return {
                "error": f"Analysis failed: {str(e)}",
                "repo": f"{owner}/{repo}",
                "analyzed_at": now.isoformat()
            }

def predict_productivity_core(daily_coding_hours, commits_per_day, pull_requests_per_week, 
                        issues_closed_per_week, active_repos, code_reviews_per_week):
    try:
        # Map the 6 input features to the 7 features the model expects:
        # ['cycle_time', 'pr_size', 'dev_satisfaction', 'deployment_frequency', 
        #  'change_failure_rate', 'cognitive_load', 'test_coverage']
        
        # Create mappings with reasonable defaults
        cycle_time = max(1, 7 - commits_per_day)  # Inverse relationship with commits
        pr_size = max(100, 500 - (pull_requests_per_week * 50))  # Smaller if more PRs
        dev_satisfaction = min(10, 5 + (daily_coding_hours * 0.5))  # Based on coding hours
        deployment_frequency = max(1, 7 - (pull_requests_per_week * 0.5))  # Related to PRs
        change_failure_rate = max(0.1, 0.5 - (code_reviews_per_week * 0.05))  # Lower with more reviews
        cognitive_load = max(1, 8 - daily_coding_hours)  # Inverse of coding hours
        test_coverage = min(1.0, 0.6 + (code_reviews_per_week * 0.05))  # Higher with reviews
        
        features = np.array([[
            cycle_time, pr_size, dev_satisfaction, deployment_frequency,
            change_failure_rate, cognitive_load, test_coverage
        ]])
        features_scaled = scaler.transform(features)
        prediction = model.predict(features_scaled)[0]
        return float(prediction)
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Prediction failed: {str(e)}")

# FastAPI Endpoints
@app.get("/")
async def root():
    return {"message": "Developer Productivity Prediction API", "status": "online"}

@app.post("/predict", response_model=ProductivityResponse)
async def predict_productivity(request: ProductivityRequest):
    try:
        prediction = predict_productivity_core(
            request.daily_coding_hours, request.commits_per_day, request.pull_requests_per_week,
            request.issues_closed_per_week, request.active_repos, request.code_reviews_per_week
        )
        return ProductivityResponse(predicted_score=prediction, status="success")
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))

@app.post("/analyze-github", response_model=GitHubAnalysisResponse)
async def analyze_github_repo(request: GitHubAnalysisRequest):
    try:
        # Validate inputs
        if not request.repo_url or not request.github_token:
            raise HTTPException(status_code=422, detail="repo_url and github_token are required")
        
        analyzer = RepoProductivityAnalyzer(request.github_token)
        metrics = analyzer.get_metrics(request.repo_url)
        
        if "error" in metrics:
            raise HTTPException(status_code=400, detail=metrics["error"])
        
        # Ensure all required metrics exist with defaults
        commits_per_day = float(metrics.get('commits_per_day', 0))
        prs_per_week = float(metrics.get('prs_per_week', 0))
        issues_per_week = float(metrics.get('issues_per_week', 0))
        
        # Transform to ML features
        ml_features = {
            'daily_coding_hours': min(commits_per_day * 2, 8),
            'commits_per_day': max(int(commits_per_day), 0),
            'pull_requests_per_week': max(int(prs_per_week), 0),
            'issues_closed_per_week': max(int(issues_per_week), 0),
            'active_repos': 1,
            'code_reviews_per_week': max(int(prs_per_week), 0)
        }
        
        prediction = predict_productivity_core(**ml_features)
        
        productivity_indicators = {
            'high_commit_frequency': commits_per_day > 1,
            'active_pr_process': prs_per_week > 2,
            'good_issue_resolution': issues_per_week > 1,
            'overall_productivity': prediction > 0.7
        }
        
        return GitHubAnalysisResponse(
            repo_metrics=metrics, 
            ml_features=ml_features,
            predicted_score=float(prediction), 
            productivity_indicators=productivity_indicators,
            status="success"
        )
    except HTTPException:
        raise
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Analysis failed: {str(e)}")

# Gradio Interface Functions
def gradio_predict(daily_coding_hours, commits_per_day, pull_requests_per_week, 
                  issues_closed_per_week, active_repos, code_reviews_per_week):
    try:
        prediction = predict_productivity_core(
            daily_coding_hours, commits_per_day, pull_requests_per_week,
            issues_closed_per_week, active_repos, code_reviews_per_week
        )
        return f"Predicted Score: {prediction:.3f}"
    except Exception as e:
        return f"Error: {str(e)}"

def gradio_github_analysis(repo_url, github_token):
    try:
        analyzer = RepoProductivityAnalyzer(github_token)
        metrics = analyzer.get_metrics(repo_url)
        
        if "error" in metrics:
            return f"Error: {metrics['error']}"
        
        ml_features = {
            'daily_coding_hours': min(metrics['commits_per_day'] * 2, 8),
            'commits_per_day': max(int(metrics['commits_per_day']), 0),
            'pull_requests_per_week': max(int(metrics['prs_per_week']), 0),
            'issues_closed_per_week': max(int(metrics['issues_per_week']), 0),
            'active_repos': 1,
            'code_reviews_per_week': max(int(metrics['prs_per_week']), 0)
        }
        
        prediction = predict_productivity_core(**ml_features)
        
        return f"""🏆 PRODUCTIVITY ANALYSIS
📊 Repository: {metrics['repo']}
⏱️  Period: {metrics['period_days']} days

📈 KEY METRICS:
• Commits/day: {metrics['commits_per_day']:.1f}
• PRs/week: {metrics['prs_per_week']:.1f}  
• Issues/week: {metrics['issues_per_week']:.1f}

🤖 ML PREDICTION: {prediction:.3f}
{'🚀 High Productivity!' if prediction > 0.7 else '⚠️ Room for improvement'}

💡 FEATURES:
• Daily coding hours: {ml_features['daily_coding_hours']}
• Commits/day: {ml_features['commits_per_day']}
• PRs/week: {ml_features['pull_requests_per_week']}
• Issues/week: {ml_features['issues_closed_per_week']}
• Active repos: {ml_features['active_repos']}
• Reviews/week: {ml_features['code_reviews_per_week']}"""
        
    except Exception as e:
        return f"Error: {str(e)}"

# Create Gradio Interface
with gr.Blocks(title="Developer Productivity Predictor") as demo:
    gr.Markdown("# 🏆 Developer Productivity Predictor")
    gr.Markdown("Predict productivity scores and analyze GitHub repositories using ML")
    
    with gr.Tab("Manual Prediction"):
        gr.Markdown("### Enter your development metrics:")
        with gr.Row():
            daily_hours = gr.Slider(1, 12, value=6, label="Daily Coding Hours")
            commits = gr.Slider(0, 20, value=3, label="Commits per Day")
            prs = gr.Slider(0, 10, value=2, label="Pull Requests per Week")
        with gr.Row():
            issues = gr.Slider(0, 15, value=3, label="Issues Closed per Week")
            repos = gr.Slider(1, 10, value=2, label="Active Repositories")
            reviews = gr.Slider(0, 20, value=5, label="Code Reviews per Week")
        
        predict_btn = gr.Button("🚀 Predict Productivity", variant="primary")
        prediction_output = gr.Textbox(label="Prediction Result", lines=2)
        
        predict_btn.click(
            gradio_predict,
            inputs=[daily_hours, commits, prs, issues, repos, reviews],
            outputs=prediction_output
        )
    
    with gr.Tab("GitHub Analysis"):
        gr.Markdown("### Analyze any GitHub repository:")
        
        repo_url_input = gr.Textbox(
            label="GitHub Repository URL",
            placeholder="https://github.com/owner/repo",
            value="https://github.com/microsoft/vscode"
        )
        token_input = gr.Textbox(
            label="GitHub Token",
            type="password",
            placeholder="ghp_xxxxxxxxxxxx"
        )
        
        analyze_btn = gr.Button("🔍 Analyze Repository", variant="primary")
        analysis_output = gr.Textbox(label="Analysis Result", lines=15)
        
        analyze_btn.click(
            gradio_github_analysis,
            inputs=[repo_url_input, token_input],
            outputs=analysis_output
        )

# Mount Gradio app to FastAPI
app = gr.mount_gradio_app(app, demo, path="/")

if __name__ == "__main__":
    uvicorn.run(app, host="0.0.0.0", port=7860)