package cmd

import (
	"fmt"
	"io/fs"
	"os"
	"path/filepath"
	"strings"

	"git.fernandovideira.com/FernandoJVideira/draft/assets"
	"github.com/spf13/cobra"
)

func init() {
	newCmd.AddCommand(apiCmd)
}

var apiCmd = &cobra.Command{
	Use:   "api",
	Short: "Create a new Draft API project",
	Long:  `Create a new Draft API project with the necessary structure and files.`,
	Run:   genAPI,
}

func genAPI(cmd *cobra.Command, args []string) {
	runNewProject(scaffoldRecipe{label: "API"})
}

func scaffoldAPI(projectDir, destSubdir, moduleName, serviceName string, useGRPC bool) error {

	destRoot := filepath.Join(projectDir, destSubdir)

	err := os.MkdirAll(destRoot, 0755)
	if err != nil {
		return fmt.Errorf("error creating project directory: %w", err)
	}

	root := "embedded/api"
	err = fs.WalkDir(assets.EmbedFS, root, func(path string, d fs.DirEntry, err error) error {

		relPath, _ := filepath.Rel(root, path)

		if !useGRPC {
			// If User chose HTTP: Remove gRPC stuff
			if strings.HasPrefix(relPath, "pb") ||
				strings.HasPrefix(relPath, "proto") ||
				strings.Contains(relPath, "handlers/grpc") ||
				strings.HasPrefix(relPath, "docs/statik") ||
				strings.HasPrefix(relPath, "docs/swagger") {
				return nil
			}
		} else {
			// If User chose gRPC: Remove HTTP stuff
			if strings.Contains(relPath, "handlers/http") {
				return nil
			}
		}

		if strings.HasSuffix(relPath, "cmd/api/main.go") {
			return nil
		}

		if d.IsDir() {
			return nil
		}

		contentBytes, err := assets.EmbedFS.ReadFile(path)
		if err != nil {
			return fmt.Errorf("error reading embedded file %s: %w", path, err)
		}
		content := string(contentBytes)

		targetPath := filepath.Join(destRoot, relPath)

		targetPath = strings.TrimSuffix(targetPath, ".tmpl")

		if err := os.MkdirAll(filepath.Dir(targetPath), 0755); err != nil {
			return fmt.Errorf("error creating directory %s: %w", filepath.Dir(targetPath), err)
		}

		newContent := strings.ReplaceAll(content, oldModuleName, moduleName)
		newContent = strings.ReplaceAll(newContent, "{{ .ModuleName }}", moduleName)
		newContent = strings.ReplaceAll(newContent, "AppTmpl", serviceName)

		return os.WriteFile(targetPath, []byte(newContent), 0644)
	})

	if err != nil {
		return fmt.Errorf("error copying template files: %w", err)
	}

	if useGRPC {
		if err := regenerateProto(destRoot, serviceName); err != nil {
			return fmt.Errorf("error regenerating proto: %w", err)
		}
	}

	// Generate main.go from template
	return genFile(
		"templates/main.go.tpl",
		"main",
		filepath.Join(destRoot, "cmd/api", "main.go"),
		MainTemplateData{
			ModuleName:  moduleName,
			ServiceName: serviceName,
			UseGRPC:     useGRPC,
		},
	)
}

func regenerateProto(projectDir, serviceName string) error {
	protoPath := filepath.Join(projectDir, "proto", fmt.Sprintf("service_%s.proto", oldModuleName))
	content, err := os.ReadFile(protoPath)
	if err != nil {
		return fmt.Errorf("error reading service proto: %w", err)
	}
	newContent := strings.Replace(string(content), "service AppTmpl {", "service "+serviceName+" {", 1)
	if err := os.WriteFile(protoPath, []byte(newContent), 0644); err != nil {
		return fmt.Errorf("error rewriting service proto: %w", err)
	}

	protoFiles, err := filepath.Glob(filepath.Join(projectDir, "proto", "*.proto"))
	if err != nil {
		return fmt.Errorf("error globbing proto files: %w", err)
	}
	args := []string{
		"--proto_path=proto",
		"--go_out=pb", "--go_opt=paths=source_relative",
		"--go-grpc_out=pb", "--go-grpc_opt=paths=source_relative",
		"--grpc-gateway_out=pb", "--grpc-gateway_opt=paths=source_relative",
		"--openapiv2_out=docs/swagger", "--openapiv2_opt=allow_merge=true,merge_file_name=" + filepath.Base(projectDir),
	}
	for _, f := range protoFiles {
		rel, _ := filepath.Rel(projectDir, f)
		args = append(args, rel)
	}
	if err := runCommand(projectDir, "protoc", args...); err != nil {
		return fmt.Errorf("error running protoc: %w", err)
	}

	return runCommand(projectDir, "statik", "-src=./docs/swagger", "-dest=./docs")
}

func installTools(useGrpc bool) error {
	tools := []string{
		"github.com/air-verse/air@latest",
		"github.com/golangci/golangci-lint/cmd/golangci-lint@latest",
		"go.uber.org/mock/mockgen@latest",
		"github.com/sqlc-dev/sqlc/cmd/sqlc@latest",
		"github.com/golang-migrate/migrate/v4/cmd/migrate@latest",
	}

	if useGrpc {
		tools = append(tools,
			"google.golang.org/protobuf/cmd/protoc-gen-go@latest",
			"google.golang.org/grpc/cmd/protoc-gen-go-grpc@latest",
			"github.com/grpc-ecosystem/grpc-gateway/v2/protoc-gen-grpc-gateway@latest",
			"github.com/grpc-ecosystem/grpc-gateway/v2/protoc-gen-openapiv2@latest",
		)
	} else {
		tools = append(tools,
			"github.com/swaggo/swag/cmd/swag@latest",
		)
	}

	for _, tool := range tools {
		if err := runCommand("", "go", "install", tool); err != nil {
			return fmt.Errorf("error installing tool %s: %w", tool, err)
		}
	}

	return nil
}