package build

import (
	"fmt"
	"github.com/leaanthony/slicer"
	"github.com/wailsapp/wails/v2/pkg/buildassets"
	"io/ioutil"
	"path/filepath"

	"github.com/wailsapp/wails/v2/internal/fs"
	"github.com/wailsapp/wails/v2/internal/html"
)

// DesktopBuilder builds applications for the desktop
type DesktopBuilder struct {
	*BaseBuilder
}

func newDesktopBuilder(options *Options) *DesktopBuilder {
	return &DesktopBuilder{
		BaseBuilder: NewBaseBuilder(options),
	}
}

// BuildAssets builds the assets for the desktop application
func (d *DesktopBuilder) BuildAssets(options *Options) error {
	var err error

	// Check assets directory exists
	if !fs.DirExists(options.ProjectData.BuildDir) {
		// Path to default assets
		err := buildassets.Install(options.ProjectData.Path, options.ProjectData.Name)
		if err != nil {
			return err
		}
	}

	// We only build assets for cgo builds
	userTags := slicer.String(options.UserTags)
	if userTags.Contains("experimental") {
		return nil
	}

	// Get a list of assets from the HTML
	assets, err := d.BaseBuilder.ExtractAssets()
	if err != nil {
		return err
	}

	// Build base assets (HTML/JS/CSS/etc)
	err = d.BuildBaseAssets(assets, options)
	if err != nil {
		return err
	}

	return nil
}

// BuildBaseAssets builds the assets for the desktop application
func (d *DesktopBuilder) BuildBaseAssets(assets *html.AssetBundle, options *Options) error {
	var err error

	outputLogger := options.Logger
	outputLogger.Print("Building assets: ")

	// Get target asset directory
	assetDir, err := fs.RelativeToCwd("build")
	if err != nil {
		return err
	}

	// Make dir if it doesn't exist
	if !fs.DirExists(assetDir) {
		err := fs.Mkdir(assetDir)
		if err != nil {
			return err
		}
	}

	// Dump assets as C
	assetsFile, err := assets.WriteToCFile(assetDir)
	if err != nil {
		return err
	}
	d.addFileToDelete(assetsFile)

	// Process Icon
	err = d.processApplicationIcon(assetDir)
	if err != nil {
		return err
	}

	// Process Tray Icons
	err = d.processTrayIcons(assetDir, options)
	if err != nil {
		return err
	}

	// Process Dialog Icons
	err = d.processDialogIcons(assetDir, options)
	if err != nil {
		return err
	}

	outputLogger.Println("Done.")

	return nil
}

// processApplicationIcon will copy a default icon if one doesn't exist, then, if
// needed, will compile the icon
func (d *DesktopBuilder) processApplicationIcon(assetDir string) error {

	// Copy default icon if one doesn't exist
	iconFile := filepath.Join(d.projectData.BuildDir, "appicon.png")
	if !fs.FileExists(iconFile) {
		err := buildassets.RegenerateAppIcon(iconFile)
		if err != nil {
			return err
		}
	}

	// Compile Icon
	return d.compileIcon(assetDir, iconFile)
}

// BuildRuntime builds the Wails javascript runtime and then converts it into a C file
func (d *DesktopBuilder) BuildRuntime(options *Options) error {

	outputLogger := options.Logger

	sourceDir := fs.RelativePath("../../../internal/runtime/js")

	if err := d.NpmInstall(sourceDir, options.Verbosity == VERBOSE); err != nil {
		return err
	}

	outputLogger.Print("Embedding Runtime: ")
	envvars := []string{"WAILSPLATFORM=" + options.Platform}
	if err := d.NpmRunWithEnvironment(sourceDir, "build:desktop", false, envvars); err != nil {
		return err
	}

	wailsJS := fs.RelativePath("../../../internal/runtime/assets/desktop.js")
	runtimeData, err := ioutil.ReadFile(wailsJS)
	if err != nil {
		return err
	}
	outputLogger.Println("done.")

	// Convert to C structure
	runtimeC := `
// runtime.c (c) 2019-Present Lea Anthony.
// Cynhyrchwyd y ffeil hon yn awtomatig. PEIDIWCH Â MODIWL
// This file was auto-generated. DO NOT MODIFY.
const unsigned char runtime[]={`
	for _, b := range runtimeData {
		runtimeC += fmt.Sprintf("0x%x, ", b)
	}
	runtimeC += "0x00};"

	// Save file
	outputFile := fs.RelativePath("../../../internal/ffenestri/runtime.c")

	if err := ioutil.WriteFile(outputFile, []byte(runtimeC), 0600); err != nil {
		return err
	}

	return nil
}