package main

import (
	_ "embed"
	"fmt"
	"golang.org/x/text/cases"
	"golang.org/x/text/language"
	"os"
	"os/exec"
	"strings"
	"text/template"
)

//go:embed templates/vue/AboutView.vue.tmpl
var aboutViewTemplate string

//go:embed templates/vue/HomeView.vue.tmpl
var homeViewTemplate string

//go:embed templates/vue/SideNavBar.vue.tmpl
var sideNavBarTemplate string

//go:embed templates/vue/Header.vue.tmpl
var headerTemplateSource string

//go:embed templates/vue/LoginLayout.vue.tmpl
var loginLayoutTemplate string

//go:embed templates/vue/MainLayout.vue.tmpl
var mainLayoutTemplate string

//go:embed templates/vue/Password.vue.tmpl
var passwordTemplate string

//go:embed templates/vue/authentication.ts.tmpl
var authenticationTemplate string

//go:embed templates/vue/App.vue.tmpl
var vueAppTemplate string

//go:embed templates/vue/router-index.ts.tmpl
var routerIndexTemplate string

//go:embed templates/vue/IconArrowFromShapeRight.vue.tmpl
var iconArrowFromShapeRightTemplate string

//go:embed templates/vue/IconHome.vue.tmpl
var iconHomeTemplate string

//go:embed templates/vue/IconGear.vue.tmpl
var iconGearTemplate string

func setupWebapp(name string) error {
	fmt.Println("Setting up webapp with Vue 3, TypeScript, Vue Router, Pinia, and ESLint with Prettier")
	cmd := exec.Command("npm", "create", "vue@latest", "--", "--ts", "--router", "--pinia", "--eslint-with-prettier", name)
	err := cmd.Run()
	if err != nil {
		return fmt.Errorf("error setting up webapp | %w", err)
	}

	fmt.Println("Switching to the new directory")
	// cd into the new directory
	err = os.Chdir(name)
	if err != nil {
		return fmt.Errorf("error changing directory | %w", err)
	}

	fmt.Println("Installing base dependencies")
	// install all dependencies and format the code
	cmd = exec.Command("npm", "install", "&&", "npm", "run", "format")
	err = cmd.Run()
	if err != nil {
		return fmt.Errorf("error changing directory | %w", err)
	}

	// make src/assets/base.css and src/assets/main.css mostly empty files
	err = os.WriteFile("src/assets/base.css", []byte(""), 0644)
	if err != nil {
		return fmt.Errorf("error writing base.css | %w", err)
	}
	err = os.WriteFile("src/assets/main.css", []byte("@import './base.css';"), 0644)
	if err != nil {
		return fmt.Errorf("error writing main.css | %w", err)
	}

	fmt.Println("Setting up Tailwind CSS")
	err = setupTailwind()
	if err != nil {
		return fmt.Errorf("error setting up tailwind | %w", err)
	}

	// clean up the default example files
	err = removeListOfFiles([]string{
		"src/components/HelloWorld.vue",
		"src/components/TheWelcome.vue",
		"src/components/WelcomeItem.vue",
		"src/views/AboutView.vue", // replace with new AboutView.vue
		"src/components/icons/IconCommunity.vue",
		"src/components/icons/IconDocumentation.vue",
		"src/components/icons/IconEcosystem.vue",
		"src/components/icons/IconSupport.vue",
		"src/components/icons/IconTooling.vue",
		"src/assets/logo.svg",
	})

	// make sure "src/layouts/" exists
	err = os.Mkdir("src/layouts", 0755)
	if err != nil {
		return fmt.Errorf("error creating layouts directory | %w", err)
	}

	// create a new about view from the aboutViewTemplate
	err = os.WriteFile("src/views/AboutView.vue", []byte(aboutViewTemplate), 0644)
	if err != nil {
		return fmt.Errorf("error writing new AboutView.vue | %w", err)
	}
	// create a new home view from the homeViewTemplate
	err = os.WriteFile("src/views/HomeView.vue", []byte(homeViewTemplate), 0644)
	if err != nil {
		return fmt.Errorf("error writing new HomeView.vue | %w", err)
	}

	// create src/components/SideNavBar.vue from a template
	err = os.WriteFile("src/components/SideNavBar.vue", []byte(sideNavBarTemplate), 0644)
	if err != nil {
		return fmt.Errorf("error writing new SideNavBar.vue | %w", err)
	}

	titleMaker := cases.Title(language.English)

	// create src/components/Header.vue from a template
	err = renderTemplate("src/components/Header.vue", headerTemplateSource, map[string]string{"AppName": strings.ToLower(name), "AppNameCaps": titleMaker.String(name)})
	if err != nil {
		return fmt.Errorf("error writing new Header.vue | %w", err)
	}

	err = renderTemplate("src/layouts/MainLayout.vue", mainLayoutTemplate, map[string]string{"AppName": strings.ToLower(name), "AppNameCaps": titleMaker.String(name)})
	if err != nil {
		return fmt.Errorf("error writing new MainLayout.vue | %w", err)
	}

	// create src/layouts/Login.vue from a template
	err = os.WriteFile("src/layouts/Login.vue", []byte(loginLayoutTemplate), 0644)
	if err != nil {
		return fmt.Errorf("error writing new Login.vue | %w", err)
	}

	straightCopies := []struct{ src, dest string }{
		{vueAppTemplate, "src/App.vue"},
		{passwordTemplate, "src/views/Password.vue"},
		{authenticationTemplate, "src/stores/authentication.ts"},
		{routerIndexTemplate, "src/router/index.ts"},
		{iconArrowFromShapeRightTemplate, "src/components/icons/IconArrowFromShapeRight.vue"},
		{iconHomeTemplate, "src/components/icons/IconHome.vue"},
		{iconGearTemplate, "src/components/icons/IconGear.vue"},
	}

	for _, srcDest := range straightCopies {
		err = os.WriteFile(srcDest.dest, []byte(srcDest.src), 0644)
		if err != nil {
			return fmt.Errorf("error writing new file %s | %w", srcDest.dest, err)
		}
	}

	fmt.Println("Exiting the new directory")
	err = os.Chdir("..")
	if err != nil {
		return fmt.Errorf("error changing directory | %w", err)
	}

	return nil
}

func renderTemplate(fileLocation string, templateSource string, templateData map[string]string) error {
	headerFile, err := os.Create(fileLocation)
	if err != nil {
		return fmt.Errorf("error creating new file %s | %w", fileLocation, err)
	}
	defer headerFile.Close()
	headerTemplate := template.Must(template.New("header").Parse(templateSource))
	err = headerTemplate.Execute(headerFile, templateData)
	if err != nil {
		return fmt.Errorf("error rendering file %s | %w", fileLocation, err)
	}
	return nil
}

func setupTailwind() error {
	// check that there is a vite.config.ts file and a package.json file
	_, err := os.Stat("vite.config.ts")
	if err != nil {
		return fmt.Errorf("error checking for vite.config.ts | %w", err)
	}
	_, err = os.Stat("package.json")
	if err != nil {
		return fmt.Errorf("error checking for package.json | %w", err)
	}

	cmd := exec.Command("npm", "install", "tailwindcss", "@tailwindcss/vite")
	err = cmd.Run()
	if err != nil {
		return fmt.Errorf("error installing tailwindcss | %w", err)
	}

	// In the vite.config.ts insert the following code after the last import statement `import tailwindcss from '@tailwindcss/vite'`
	err = insertImportStatement("import tailwindcss from '@tailwindcss/vite'", "vite.config.ts")
	if err != nil {
		return fmt.Errorf("error inserting import statement | %w", err)
	}

	// In the vite.config.ts insert the following code after the last plugin usage `tailwindcss(),`
	err = insertPluginUsage("    tailwindcss(),", "vite.config.ts")
	if err != nil {
		return fmt.Errorf("error inserting plugin usage | %w", err)
	}

	// in the base.css file add an @import statement for tailwind
	// check that './src/assets/base.css' exists
	_, err = os.Stat("./src/assets/base.css")
	if err != nil {
		return fmt.Errorf("error checking for base.css | %w", err)
	}
	err = insertAtTopLineOfFile("@import \"tailwindcss\";", "./src/assets/base.css")
	if err != nil {
		return fmt.Errorf("error inserting import statement | %w", err)
	}
	return nil
}

func insertImportStatement(importStatement string, filename string) error {
	fileContent, err := os.ReadFile(fmt.Sprintf(".%c%s", os.PathSeparator, filename))
	if err != nil {
		return fmt.Errorf("error reading %s | %w", filename, err)
	}

	fileLines := strings.Split(strings.ReplaceAll(string(fileContent), "\r\n", "\n"), "\n")
	lastImportIndex := -1
	// finds the last import statement in the file and appends after that one
	for i, line := range fileLines {
		if strings.HasPrefix(line, "import") {
			lastImportIndex = i
		}
	}
	if lastImportIndex != -1 {
		fileLines = append(fileLines[:lastImportIndex+1], append([]string{importStatement}, fileLines[lastImportIndex+1:]...)...)
	} else {
		// add the import to the top of the file
		fileLines = append([]string{importStatement}, fileLines...)
	}

	err = os.WriteFile(filename, []byte(strings.Join(fileLines, "\n")), 0644)
	if err != nil {
		return fmt.Errorf("error writing vite.config.ts | %w", err)
	}
	return nil
}

func insertPluginUsage(pluginUsage string, filename string) error {
	fileContent, err := os.ReadFile(fmt.Sprintf(".%c%s", os.PathSeparator, filename))
	if err != nil {
		return fmt.Errorf("error reading %s | %w", filename, err)
	}

	fileLines := strings.Split(strings.ReplaceAll(string(fileContent), "\r\n", "\n"), "\n")
	startOfPluginsIndex := -1
	// finds the `plugins: [` line in the file and appends after that one
	for i, line := range fileLines {
		if strings.Contains(line, "plugins: [") {
			startOfPluginsIndex = i
		}
	}
	if startOfPluginsIndex != -1 {
		fileLines = append(fileLines[:startOfPluginsIndex+1], append([]string{pluginUsage}, fileLines[startOfPluginsIndex+1:]...)...)
	} else {
		// add the import to the top of the file
		fileLines = append([]string{pluginUsage}, fileLines...)
	}

	err = os.WriteFile(filename, []byte(strings.Join(fileLines, "\n")), 0644)
	if err != nil {
		return fmt.Errorf("error writing vite.config.ts | %w", err)
	}
	return nil
}

func insertAtTopLineOfFile(content string, filename string) error {
	fileContent, err := os.ReadFile(fmt.Sprintf(".%c%s", os.PathSeparator, filename))
	if err != nil {
		return fmt.Errorf("error reading %s | %w", filename, err)
	}

	fileLines := strings.Split(strings.ReplaceAll(string(fileContent), "\r\n", "\n"), "\n")
	fileLines = append([]string{content}, fileLines...)

	err = os.WriteFile(filename, []byte(strings.Join(fileLines, "\n")), 0644)
	if err != nil {
		return fmt.Errorf("error writing vite.config.ts | %w", err)
	}
	return nil
}

func removeListOfFiles(files []string) error {

	for _, file := range files {
		err := os.Remove(file)
		if err != nil {
			return fmt.Errorf("error removing %s | %w", file, err)
		}
	}

	return nil
}