// Copyright (c) 2013 GPMGo Members. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.

package cmd

import (
	"encoding/json"
	"fmt"
	"os"
	"runtime"
	"strings"

	"github.com/GPMGo/gopm/utils"
	"github.com/GPMGo/node"
)

var (
	removeCache map[string]bool // Saves packages that have been removed.
)

var CmdRemove = &Command{
	UsageLine: "remove [remove flags] <packages|bundles|snapshots>",
}

func init() {
	removeCache = make(map[string]bool)
	CmdRemove.Run = runRemove
}

func runRemove(cmd *Command, args []string) {
	// Check length of arguments.
	if len(args) < 1 {
		fmt.Printf(fmt.Sprintf("%s\n", PromptMsg["NoPackage"]))
		return
	}

	var nodes []*node.Node
	// Check if it is a bundle or snapshot.
	switch {
	case CmdRemove.Flags["-b"]:
		bundle := args[0]
		// Check local bundles.
		nodes = checkLocalBundles(bundle)
		if len(nodes) > 0 {
			// Check with users if continue.
			utils.ColorPrint(fmt.Sprintf(fmt.Sprintf("%s\n", PromptMsg["BundleInfo"]), bundle))
			for _, n := range nodes {
				fmt.Printf("[%s] -> %s: %s.\n", n.ImportPath, n.Type, n.Value)
			}
			fmt.Printf(fmt.Sprintf("%s\n", PromptMsg["ContinueRemove"]))
			var option string
			fmt.Fscan(os.Stdin, &option)
			if strings.ToLower(option) != "y" {
				os.Exit(0)
				return
			}
		} else {
			// Check from server.
			// TODO: api.GetBundleInfo()
			fmt.Println("Unable to find bundle, and we cannot check with server right now.")
		}
	case CmdRemove.Flags["-s"]:
		fmt.Println("gopm has not supported snapshot yet.")
		// TODO: api.GetSnapshotInfo()
	default:
		// Generate temporary nodes.
		nodes = make([]*node.Node, len(args))
		for i := range nodes {
			nodes[i] = new(node.Node)
			nodes[i].ImportPath = args[i]
		}
	}

	// Removes packages.
	removePackages(nodes)

	// Save local nodes to file.
	fw, err := os.Create(AppPath + "data/nodes.json")
	if err != nil {
		utils.ColorPrint(fmt.Sprintf(fmt.Sprintf("[ERROR] runRemove -> %s\n", PromptMsg["OpenFile"]), err))
		return
	}
	defer fw.Close()
	fbytes, err := json.MarshalIndent(&LocalNodes, "", "\t")
	if err != nil {
		utils.ColorPrint(fmt.Sprintf(fmt.Sprintf("[ERROR] runRemove -> %s\n", PromptMsg["ParseJSON"]), err))
		return
	}
	fw.Write(fbytes)
}

// removePackages removes packages from local file system.
func removePackages(nodes []*node.Node) {
	// Check all packages, they may be bundles, snapshots or raw packages path.
	for _, n := range nodes {
		// Check if it is a bundle or snapshot.
		if utils.IsValidRemotePath(n.ImportPath) {
			if !removeCache[n.ImportPath] {
				// Remove package.
				nod, imports := removePackage(n)
				if len(imports) > 0 {
					fmt.Println("Check denpendencies for removing package has not been supported.")
				}

				// Remove record in local nodes.
				if nod != nil {
					removeNode(nod)
				}
			}
		} else {
			// Invalid import path.
			fmt.Printf(fmt.Sprintf("%s\n", PromptMsg["SkipInvalidPath"]), n.ImportPath)
		}
	}
}

// removeNode removes node from local nodes.
func removeNode(n *node.Node) {
	// Check if this node exists.
	for i, v := range LocalNodes {
		if n.ImportPath == v.ImportPath {
			LocalNodes = append(LocalNodes[:i], LocalNodes[i+1:]...)
			return
		}
	}
}

// removePackage removes package from local file system.
func removePackage(nod *node.Node) (*node.Node, []string) {
	// Find package in GOPATH.
	paths := utils.GetGOPATH()
	for _, p := range paths {
		absPath := p + "/src/" + utils.GetProjectPath(nod.ImportPath) + "/"
		if utils.IsExist(absPath) {
			fmt.Printf(fmt.Sprintf("%s\n", PromptMsg["RemovePackage"]), nod.ImportPath)
			// Remove files.
			os.RemoveAll(absPath)
			// Remove file in GOPATH/bin
			proName := utils.GetExecuteName(nod.ImportPath)
			paths := utils.GetGOPATH()
			var gopath string

			for _, v := range paths {
				if utils.IsExist(v + "/bin/" + proName) {
					gopath = v // Don't need to find again.
					os.Remove(v + "/bin/" + proName)
				}
			}

			pkgList := []string{nod.ImportPath}
			removePackageFiles(gopath, pkgList)

			return nod, nil
		}
	}

	// Cannot find package.
	fmt.Printf(fmt.Sprintf("%s\n", PromptMsg["PackageNotFound"]), nod.ImportPath)
	return nil, nil
}

// removePackageFiles removes package files in $GOPATH/pkg.
func removePackageFiles(gopath string, pkgList []string) {
	var paths []string
	// Check if need to find GOPATH.
	if len(gopath) == 0 {
		paths = utils.GetGOPATH()
	} else {
		paths = append(paths, gopath)
	}

	pkgPath := "/pkg/" + runtime.GOOS + "_" + runtime.GOARCH + "/"
	for _, p := range pkgList {
		for _, g := range paths {
			os.RemoveAll(g + pkgPath + p + "/")
			os.Remove(g + pkgPath + p + ".a")
		}
	}
}