package main

import (
	"bufio"
	"context"
	"fmt"
	"log"
	"os"
	"os/signal"
	"strings"
	"syscall"

	"tell-me/config"
	"tell-me/llm"
	"tell-me/mcp"

	"github.com/sashabaranov/go-openai"
)

func main() {
	// Load configuration
	cfg, err := config.Load()
	if err != nil {
		fmt.Fprintf(os.Stderr, "Error loading configuration: %v\n", err)
		fmt.Fprintf(os.Stderr, "Please create ~/.config/tell-me.yaml from tell-me.yaml.example\n")
		os.Exit(1)
	}

	ctx := context.Background()

	// Initialize MCP manager
	mcpManager := mcp.NewManager(ctx)
	defer mcpManager.Close()

	// Connect to MCP servers if configured
	if len(cfg.MCPServers) > 0 {
		if err := mcpManager.ConnectServers(cfg.MCPServers); err != nil {
			log.Printf("Warning: Failed to connect to some MCP servers: %v", err)
		}
	}

	// Create LLM client with MCP manager
	client := llm.NewClient(
		cfg.APIURL,
		cfg.APIKey,
		cfg.Model,
		cfg.ContextSize,
		cfg.SearXNGURL,
		mcpManager,
	)

	// Initialize conversation with system prompt from config
	messages := []openai.ChatCompletionMessage{
		{
			Role:    openai.ChatMessageRoleSystem,
			Content: llm.GetSystemPrompt(cfg.Prompt),
		},
	}

	// Check if arguments are provided (non-interactive mode)
	if len(os.Args) > 1 {
		query := strings.Join(os.Args[1:], " ")
		// Display MCP status in non-interactive mode if servers are configured
		if len(cfg.MCPServers) > 0 {
			displayMCPStatusInline(mcpManager)
		}
		processQuery(ctx, client, messages, query)
		return
	}

	// Setup signal handling for Ctrl-C
	sigChan := make(chan os.Signal, 1)
	signal.Notify(sigChan, os.Interrupt, syscall.SIGTERM)
	go func() {
		<-sigChan
		fmt.Println("\n\nGoodbye!")
		os.Exit(0)
	}()

	// Print welcome message with MCP status
	fmt.Println("╔════════════════════════════════════════════════════════════════╗")
	fmt.Println("║                         Tell-Me CLI                            ║")
	fmt.Println("║          AI-powered search with local LLM support              ║")
	fmt.Println("╚════════════════════════════════════════════════════════════════╝")
	fmt.Println()
	fmt.Printf("Using model: %s\n", cfg.Model)
	fmt.Printf("SearXNG: %s\n", cfg.SearXNGURL)

	// Display MCP server status
	if len(cfg.MCPServers) > 0 {
		fmt.Println()
		displayMCPStatusInline(mcpManager)
	}

	fmt.Println()
	fmt.Println("Type your questions below. Type 'exit' or 'quit' to exit, or press Ctrl-C.")
	fmt.Println("────────────────────────────────────────────────────────────────")
	fmt.Println()

	// Create scanner for user input
	scanner := bufio.NewScanner(os.Stdin)

	for {
		// Prompt for user input
		fmt.Print("❯ ")
		if !scanner.Scan() {
			break
		}

		userInput := strings.TrimSpace(scanner.Text())

		// Check for exit commands
		if userInput == "exit" || userInput == "quit" {
			fmt.Println("\nGoodbye!")
			break
		}

		// Skip empty input
		if userInput == "" {
			continue
		}

		// Process the query
		messages = processQuery(ctx, client, messages, userInput)
	}

	if err := scanner.Err(); err != nil {
		fmt.Fprintf(os.Stderr, "Error reading input: %v\n", err)
		os.Exit(1)
	}
}

// processQuery handles a single query and returns updated messages
func processQuery(ctx context.Context, client *llm.Client, messages []openai.ChatCompletionMessage, userInput string) []openai.ChatCompletionMessage {
	// Add user message to conversation
	messages = append(messages, openai.ChatCompletionMessage{
		Role:    openai.ChatMessageRoleUser,
		Content: userInput,
	})

	// Print blank line before streaming starts
	fmt.Println()

	// Get response from LLM with streaming
	_, updatedMessages, err := client.Chat(ctx, messages, func(chunk string) {
		fmt.Print(chunk)
	})
	if err != nil {
		fmt.Fprintf(os.Stderr, "\nError: %v\n\n", err)
		// Remove the failed user message
		return messages[:len(messages)-1]
	}

	// Update messages with the full conversation history
	messages = updatedMessages

	// Print newline after streaming completes
	fmt.Println()
	fmt.Println()

	return messages
}

// displayMCPStatusInline shows MCP server status in the header
func displayMCPStatusInline(manager *mcp.Manager) {
	statuses := manager.GetDetailedStatus()

	if len(statuses) == 0 {
		return
	}

	fmt.Print("MCP Servers: ")

	for i, status := range statuses {
		if i > 0 {
			fmt.Print(", ")
		}

		if status.Error != "" {
			// Red X for error
			fmt.Printf("\033[31m✗\033[0m %s", status.Name)
		} else {
			// Green checkmark for OK
			fmt.Printf("\033[32m✓\033[0m %s (%d tools)", status.Name, len(status.Tools))
		}
	}
	fmt.Println()
}