package main

import (
	"context"
	"fmt"
	"log"
	"os"
	"time"

	"github.com/gofiber/fiber/v2"
	"github.com/gofiber/fiber/v2/middleware/cors"
	"github.com/gofiber/fiber/v2/middleware/logger"
	"github.com/gooseek/backend/internal/db"
	"github.com/gooseek/backend/internal/files"
	"github.com/gooseek/backend/internal/llm"
	"github.com/gooseek/backend/pkg/config"
	"github.com/gooseek/backend/pkg/middleware"
)

func main() {
	cfg, err := config.Load()
	if err != nil {
		log.Fatal("Failed to load config:", err)
	}

	var database *db.PostgresDB
	var fileRepo *db.FileRepository

	if cfg.DatabaseURL != "" {
		database, err = db.NewPostgresDB(cfg.DatabaseURL)
		if err != nil {
			log.Printf("Database unavailable: %v", err)
		} else {
			ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
			if err := database.RunMigrations(ctx); err != nil {
				log.Printf("Migration warning: %v", err)
			}
			cancel()
			defer database.Close()

			fileRepo = db.NewFileRepository(database)
			log.Println("PostgreSQL connected")
		}
	}

	var llmClient llm.Client
	if cfg.OpenAIAPIKey != "" {
		llmClient, err = llm.NewClient(llm.ProviderConfig{
			ProviderID: "openai",
			ModelKey:   "gpt-4o",
			APIKey:     cfg.OpenAIAPIKey,
		})
		if err != nil {
			log.Printf("Failed to create OpenAI client: %v", err)
		}
	} else if cfg.AnthropicAPIKey != "" {
		llmClient, err = llm.NewClient(llm.ProviderConfig{
			ProviderID: "anthropic",
			ModelKey:   "claude-3-5-sonnet-20241022",
			APIKey:     cfg.AnthropicAPIKey,
		})
		if err != nil {
			log.Printf("Failed to create Anthropic client: %v", err)
		}
	}

	storagePath := os.Getenv("FILE_STORAGE_PATH")
	if storagePath == "" {
		storagePath = "/tmp/gooseek-files"
	}

	var fileAnalyzer *files.FileAnalyzer
	if llmClient != nil {
		fileAnalyzer = files.NewFileAnalyzer(llmClient, storagePath)
	}

	app := fiber.New(fiber.Config{
		BodyLimit:    100 * 1024 * 1024,
		ReadTimeout:  60 * time.Second,
		WriteTimeout: 60 * time.Second,
	})

	app.Use(logger.New())
	app.Use(cors.New())

	if cfg.JWTSecret != "" || cfg.AuthSvcURL != "" {
		app.Use(middleware.JWT(middleware.JWTConfig{
			Secret:     cfg.JWTSecret,
			AuthSvcURL: cfg.AuthSvcURL,
			AllowGuest: false,
			SkipPaths:  []string{"/health", "/ready"},
		}))
	}

	app.Get("/health", func(c *fiber.Ctx) error {
		return c.JSON(fiber.Map{"status": "ok"})
	})

	app.Get("/ready", func(c *fiber.Ctx) error {
		return c.JSON(fiber.Map{"status": "ready"})
	})

	api := app.Group("/api/v1/files")

	api.Post("/upload", func(c *fiber.Ctx) error {
		if fileRepo == nil || fileAnalyzer == nil {
			return c.Status(503).JSON(fiber.Map{"error": "Service unavailable"})
		}

		userID := middleware.GetUserID(c)
		if userID == "" {
			return c.Status(401).JSON(fiber.Map{"error": "Unauthorized"})
		}

		file, err := c.FormFile("file")
		if err != nil {
			return c.Status(400).JSON(fiber.Map{"error": "No file uploaded"})
		}

		if file.Size > 50*1024*1024 {
			return c.Status(400).JSON(fiber.Map{"error": "File too large (max 50MB)"})
		}

		f, err := file.Open()
		if err != nil {
			return c.Status(500).JSON(fiber.Map{"error": "Failed to read file"})
		}
		defer f.Close()

		storagePath, fileSize, err := fileAnalyzer.SaveFile(file.Filename, f)
		if err != nil {
			return c.Status(500).JSON(fiber.Map{"error": "Failed to save file"})
		}

		buf := make([]byte, 512)
		f.Seek(0, 0)
		f.Read(buf)
		mimeType := files.DetectMimeType(file.Filename, buf)

		uploadedFile := &db.UploadedFile{
			UserID:      userID,
			Filename:    file.Filename,
			FileType:    mimeType,
			FileSize:    fileSize,
			StoragePath: storagePath,
			Metadata:    map[string]interface{}{},
		}

		if err := fileRepo.Create(c.Context(), uploadedFile); err != nil {
			fileAnalyzer.DeleteFile(storagePath)
			return c.Status(500).JSON(fiber.Map{"error": "Failed to save file record"})
		}

		go func() {
			ctx, cancel := context.WithTimeout(context.Background(), 5*time.Minute)
			defer cancel()

			result, err := fileAnalyzer.AnalyzeFile(ctx, storagePath, mimeType)
			if err != nil {
				log.Printf("File analysis failed for %s: %v", uploadedFile.ID, err)
				return
			}

			fileRepo.UpdateExtractedText(ctx, uploadedFile.ID, result.ExtractedText)
		}()

		return c.Status(201).JSON(fiber.Map{
			"id":       uploadedFile.ID,
			"filename": uploadedFile.Filename,
			"fileType": uploadedFile.FileType,
			"fileSize": uploadedFile.FileSize,
			"status":   "processing",
		})
	})

	api.Get("/", func(c *fiber.Ctx) error {
		if fileRepo == nil {
			return c.Status(503).JSON(fiber.Map{"error": "Service unavailable"})
		}

		userID := middleware.GetUserID(c)
		if userID == "" {
			return c.Status(401).JSON(fiber.Map{"error": "Unauthorized"})
		}

		limit := c.QueryInt("limit", 50)
		offset := c.QueryInt("offset", 0)

		files, err := fileRepo.GetByUserID(c.Context(), userID, limit, offset)
		if err != nil {
			return c.Status(500).JSON(fiber.Map{"error": "Failed to get files"})
		}

		return c.JSON(fiber.Map{"files": files})
	})

	api.Get("/:id", func(c *fiber.Ctx) error {
		if fileRepo == nil {
			return c.Status(503).JSON(fiber.Map{"error": "Service unavailable"})
		}

		fileID := c.Params("id")
		userID := middleware.GetUserID(c)

		file, err := fileRepo.GetByID(c.Context(), fileID)
		if err != nil || file == nil {
			return c.Status(404).JSON(fiber.Map{"error": "File not found"})
		}

		if file.UserID != userID {
			return c.Status(403).JSON(fiber.Map{"error": "Access denied"})
		}

		return c.JSON(file)
	})

	api.Get("/:id/content", func(c *fiber.Ctx) error {
		if fileRepo == nil {
			return c.Status(503).JSON(fiber.Map{"error": "Service unavailable"})
		}

		fileID := c.Params("id")
		userID := middleware.GetUserID(c)

		file, err := fileRepo.GetByID(c.Context(), fileID)
		if err != nil || file == nil {
			return c.Status(404).JSON(fiber.Map{"error": "File not found"})
		}

		if file.UserID != userID {
			return c.Status(403).JSON(fiber.Map{"error": "Access denied"})
		}

		return c.JSON(fiber.Map{
			"id":            file.ID,
			"filename":      file.Filename,
			"extractedText": file.ExtractedText,
		})
	})

	api.Post("/:id/analyze", func(c *fiber.Ctx) error {
		if fileRepo == nil || fileAnalyzer == nil {
			return c.Status(503).JSON(fiber.Map{"error": "Service unavailable"})
		}

		fileID := c.Params("id")
		userID := middleware.GetUserID(c)

		file, err := fileRepo.GetByID(c.Context(), fileID)
		if err != nil || file == nil {
			return c.Status(404).JSON(fiber.Map{"error": "File not found"})
		}

		if file.UserID != userID {
			return c.Status(403).JSON(fiber.Map{"error": "Access denied"})
		}

		result, err := fileAnalyzer.AnalyzeFile(c.Context(), file.StoragePath, file.FileType)
		if err != nil {
			return c.Status(500).JSON(fiber.Map{"error": "Analysis failed: " + err.Error()})
		}

		fileRepo.UpdateExtractedText(c.Context(), fileID, result.ExtractedText)

		return c.JSON(result)
	})

	api.Delete("/:id", func(c *fiber.Ctx) error {
		if fileRepo == nil || fileAnalyzer == nil {
			return c.Status(503).JSON(fiber.Map{"error": "Service unavailable"})
		}

		fileID := c.Params("id")
		userID := middleware.GetUserID(c)

		file, err := fileRepo.GetByID(c.Context(), fileID)
		if err != nil || file == nil {
			return c.Status(404).JSON(fiber.Map{"error": "File not found"})
		}

		if file.UserID != userID {
			return c.Status(403).JSON(fiber.Map{"error": "Access denied"})
		}

		fileAnalyzer.DeleteFile(file.StoragePath)

		if err := fileRepo.Delete(c.Context(), fileID); err != nil {
			return c.Status(500).JSON(fiber.Map{"error": "Failed to delete file"})
		}

		return c.Status(204).Send(nil)
	})

	port := getEnvInt("FILE_SVC_PORT", 3026)
	log.Printf("file-svc listening on :%d", port)
	log.Fatal(app.Listen(fmt.Sprintf(":%d", port)))
}

func getEnvInt(key string, defaultValue int) int {
	if val := os.Getenv(key); val != "" {
		var result int
		if _, err := fmt.Sscanf(val, "%d", &result); err == nil {
			return result
		}
	}
	return defaultValue
}