// Copyright 2014 The Gogs Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.

package base

import (
	"crypto/md5"
	"encoding/hex"
	"fmt"
	"html/template"
	"time"
)

// Encode string to md5 hex value
func EncodeMd5(str string) string {
	m := md5.New()
	m.Write([]byte(str))
	return hex.EncodeToString(m.Sum(nil))
}

// Seconds-based time units
const (
	Minute = 60
	Hour   = 60 * Minute
	Day    = 24 * Hour
	Week   = 7 * Day
	Month  = 30 * Day
	Year   = 12 * Month
)

func Str2html(raw string) template.HTML {
	return template.HTML(raw)
}

// TimeSince calculates the time interval and generate user-friendly string.
func TimeSince(then time.Time) string {
	now := time.Now()

	lbl := "ago"
	diff := now.Unix() - then.Unix()
	if then.After(now) {
		lbl = "from now"
		diff = then.Unix() - now.Unix()
	}

	switch {

	case diff <= 0:
		return "now"
	case diff <= 2:
		return fmt.Sprintf("1 second %s", lbl)
	case diff < 1*Minute:
		return fmt.Sprintf("%d seconds %s", diff, lbl)

	case diff < 2*Minute:
		return fmt.Sprintf("1 minute %s", lbl)
	case diff < 1*Hour:
		return fmt.Sprintf("%d minutes %s", diff/Minute, lbl)

	case diff < 2*Hour:
		return fmt.Sprintf("1 hour %s", lbl)
	case diff < 1*Day:
		return fmt.Sprintf("%d hours %s", diff/Hour, lbl)

	case diff < 2*Day:
		return fmt.Sprintf("1 day %s", lbl)
	case diff < 1*Week:
		return fmt.Sprintf("%d days %s", diff/Day, lbl)

	case diff < 2*Week:
		return fmt.Sprintf("1 week %s", lbl)
	case diff < 1*Month:
		return fmt.Sprintf("%d weeks %s", diff/Week, lbl)

	case diff < 2*Month:
		return fmt.Sprintf("1 month %s", lbl)
	case diff < 1*Year:
		return fmt.Sprintf("%d months %s", diff/Month, lbl)

	case diff < 18*Month:
		return fmt.Sprintf("1 year %s", lbl)
	}
	return then.String()
}

// Subtract deals with subtraction of all types of number.
func Subtract(left interface{}, right interface{}) interface{} {
	var rleft, rright int64
	var fleft, fright float64
	var isInt bool = true
	switch left.(type) {
	case int:
		rleft = int64(left.(int))
	case int8:
		rleft = int64(left.(int8))
	case int16:
		rleft = int64(left.(int16))
	case int32:
		rleft = int64(left.(int32))
	case int64:
		rleft = left.(int64)
	case float32:
		fleft = float64(left.(float32))
		isInt = false
	case float64:
		fleft = left.(float64)
		isInt = false
	}

	switch right.(type) {
	case int:
		rright = int64(right.(int))
	case int8:
		rright = int64(right.(int8))
	case int16:
		rright = int64(right.(int16))
	case int32:
		rright = int64(right.(int32))
	case int64:
		rright = right.(int64)
	case float32:
		fright = float64(left.(float32))
		isInt = false
	case float64:
		fleft = left.(float64)
		isInt = false
	}

	if isInt {
		return rleft - rright
	} else {
		return fleft + float64(rleft) - (fright + float64(rright))
	}
}

type Actioner interface {
	GetOpType() int
	GetActUserName() string
	GetRepoName() string
}

// ActionIcon accepts a int that represents action operation type
// and returns a icon class name.
func ActionIcon(opType int) string {
	switch opType {
	case 1: // Create repository.
		return "plus-circle"
	default:
		return "invalid type"
	}
}

const (
	CreateRepoTpl = `<a href="/user/%s">%s</a> created repository <a href="/%s/%s">%s</a>`
)

// ActionDesc accepts int that represents action operation type
// and returns the description.
func ActionDesc(act Actioner) string {
	actUserName := act.GetActUserName()
	repoName := act.GetRepoName()
	switch act.GetOpType() {
	case 1: // Create repository.
		return fmt.Sprintf(CreateRepoTpl, actUserName, actUserName, actUserName, repoName, repoName)
	default:
		return "invalid type"
	}
}