package handlers

import (
	// Keep context for future use in actual cloud calls
	"fmt"
	"net/http"

	"git.linuxforward.com/byop/byop-engine/cloud"
	"git.linuxforward.com/byop/byop-engine/models"
	"github.com/gin-gonic/gin"
)

// ProviderHandler handles provider-related operations
type ProviderHandler struct {
	// No specific dependencies for now, but a ProviderService might be added later
	// for more complex logic or if providers are stored in a DB.
}

// NewProviderHandler creates a new ProviderHandler
func NewProviderHandler() *ProviderHandler {
	return &ProviderHandler{}
}

// RegisterRoutes registers routes for provider operations
func (h *ProviderHandler) RegisterRoutes(r *gin.RouterGroup) {
	r.GET("/", h.ListProviders)
	// r.POST("/", h.CreateProvider) // Assuming CreateProvider would involve DB interaction
	r.GET("/:id", h.GetProvider)
	// r.PUT("/:id", h.UpdateProvider) // Assuming UpdateProvider would involve DB interaction
	// r.DELETE("/:id", h.DeleteProvider) // Assuming DeleteProvider would involve DB interaction
	r.GET("/:id/regions", h.GetProviderRegions)
	r.POST("/:id/validate", h.ValidateProviderCredentials)
}

// ListProviders returns all supported providers
func (h *ProviderHandler) ListProviders(c *gin.Context) {
	providers := cloud.GetSupportedProviders() // This returns []string
	if len(providers) == 0 {
		appErr := models.NewErrNotFound("no_providers_found", fmt.Errorf("No supported providers found"))
		models.RespondWithError(c, appErr)
		return
	}

	c.JSON(http.StatusOK, providers) // Returns a JSON array of strings
}

// GetProvider returns a specific provider by its ID (name)
func (h *ProviderHandler) GetProvider(c *gin.Context) {
	ctx := c.Request.Context() // Get context, though not used for current static implementation
	_ = ctx                    // Avoid unused variable error if not used yet in this specific function
	providerName := c.Param("id")

	supportedProviders := cloud.GetSupportedProviders()
	found := false
	for _, sp := range supportedProviders {
		if sp == providerName {
			found = true
			break
		}
	}

	if !found {
		appErr := models.NewErrNotFound("provider_not_found", fmt.Errorf("Provider with name '%s' not found or not supported", providerName))
		models.RespondWithError(c, appErr)
		return
	}

	// Return basic information about the provider
	c.JSON(http.StatusOK, gin.H{"name": providerName, "status": "supported"})
}

// GetProviderRegions returns available regions for a provider
func (h *ProviderHandler) GetProviderRegions(c *gin.Context) {
	ctx := c.Request.Context() // Get context, to be used for actual cloud calls
	providerName := c.Param("id")

	// Validate if provider is supported
	supportedProviders := cloud.GetSupportedProviders()
	isSupported := false
	for _, sp := range supportedProviders {
		if sp == providerName {
			isSupported = true
			break
		}
	}

	if !isSupported {
		appErr := models.NewErrNotFound("provider_not_supported", fmt.Errorf("Provider '%s' is not supported", providerName))
		models.RespondWithError(c, appErr)
		return
	}

	// Placeholder: Replace with actual calls to cloud.Provider.ListRegions(ctx)
	// For now, using static list. ctx is available for when real calls are made.
	_ = ctx // Explicitly use ctx to avoid "unused" error if no cloud calls yet

	var regions []string

	switch providerName {
	case "aws":
		regions = []string{"us-east-1", "us-west-2", "eu-west-1"} // Example static regions
	case "digitalocean":
		regions = []string{"nyc1", "sfo3", "lon1"} // Example static regions
	case "ovh":
		regions = []string{"GRA", "SBG", "BHS"} // Example static regions
	default:
		// This case should ideally not be hit if validation above is correct
		// and the switch covers all supported providers from cloud.GetSupportedProviders().
		appErr := models.NewErrInternalServer("provider_regions_not_implemented", fmt.Errorf("Regions not implemented for provider '%s'", providerName))
		models.RespondWithError(c, appErr)
		return
	}

	c.JSON(http.StatusOK, regions)
}

// ValidateProviderCredentials validates provider credentials
func (h *ProviderHandler) ValidateProviderCredentials(c *gin.Context) {
	ctx := c.Request.Context() // Get context, to be used for actual cloud calls
	providerName := c.Param("id")

	// Validate if provider is supported
	supportedProviders := cloud.GetSupportedProviders()
	isSupported := false
	for _, sp := range supportedProviders {
		if sp == providerName {
			isSupported = true
			break
		}
	}

	if !isSupported {
		appErr := models.NewErrNotFound("provider_not_supported_for_validation", fmt.Errorf("Provider '%s' is not supported for credential validation", providerName))
		models.RespondWithError(c, appErr)
		return
	}

	var credsBody struct {
		AccessKeyID     string `json:"access_key_id"`
		SecretAccessKey string `json:"secret_access_key"`
		Token           string `json:"token"`      // For AWS STS, DO API token, OVH tokens etc.
		ProjectID       string `json:"project_id"` // For GCP, OVH
		Region          string `json:"region"`     // Optional, might be needed for some validation endpoints
	}

	if err := c.ShouldBindJSON(&credsBody); err != nil {
		appErr := models.NewErrValidation("invalid_credentials_format", map[string]string{"body": "Invalid request body for credentials"}, err)
		models.RespondWithError(c, appErr)
		return
	}

	// Placeholder: Replace with actual calls to a provider method like provider.ValidateCredentials(ctx, creds)
	// ctx is available for when real calls are made.
	_ = ctx // Explicitly use ctx to avoid "unused" error if no cloud calls yet

	var isValid bool
	var validationError error // To store error from actual validation logic

	switch providerName {
	case "aws":
		// e.g., isValid, validationError = cloud.ValidateAWSCredentials(ctx, credsBody.AccessKeyID, credsBody.SecretAccessKey, credsBody.Token, credsBody.Region)
		isValid = true // Assume valid for now
	case "digitalocean":
		// e.g., isValid, validationError = cloud.ValidateDOCredentials(ctx, credsBody.Token)
		isValid = true // Assume valid for now
	case "ovh":
		// e.g., isValid, validationError = cloud.ValidateOVHCredentials(ctx, ...)
		isValid = true // Assume valid for now
	default:
		// This case should ideally not be hit if validation above is correct.
		appErr := models.NewErrInternalServer("provider_validation_not_implemented", fmt.Errorf("Credential validation not implemented for provider '%s'", providerName))
		models.RespondWithError(c, appErr)
		return
	}

	if validationError != nil {
		appErr := models.NewErrInternalServer("credential_validation_error", fmt.Errorf("Error validating credentials for %s: %w", providerName, validationError))
		models.RespondWithError(c, appErr)
		return
	}

	if !isValid {
		appErr := models.NewErrUnauthorized("invalid_provider_credentials", fmt.Errorf("Credentials for provider %s are invalid", providerName))
		models.RespondWithError(c, appErr)
		return
	}

	c.JSON(http.StatusOK, gin.H{"valid": true, "message": "Credentials validated successfully"})
}
