1//
  2// Copyright (c) 2019 Ted Unangst <tedu@tedunangst.com>
  3//
  4// Permission to use, copy, modify, and distribute this software for any
  5// purpose with or without fee is hereby granted, provided that the above
  6// copyright notice and this permission notice appear in all copies.
  7//
  8// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  9// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 10// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 11// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 12// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 13// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 14// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 15
 16package main
 17
 18import (
 19	"bufio"
 20	"bytes"
 21	"crypto/sha512"
 22	"fmt"
 23	"image"
 24	"image/png"
 25	"net/http"
 26	"regexp"
 27	"strconv"
 28	"strings"
 29
 30	"github.com/gorilla/mux"
 31)
 32
 33var avatarcolors = [4][4]byte{
 34	{16, 0, 48, 255},
 35	{48, 0, 96, 255},
 36	{72, 0, 144, 255},
 37	{96, 0, 192, 255},
 38}
 39
 40func loadAvatarColors() {
 41	var colors string
 42	getconfig("avatarcolors", &colors)
 43	if colors == "" {
 44		return
 45	}
 46	r := bufio.NewReader(strings.NewReader(colors))
 47	for i := 0; i < 4; i++ {
 48		l, _ := r.ReadString(' ')
 49		for l == " " {
 50			l, _ = r.ReadString(' ')
 51		}
 52		l = strings.Trim(l, "# \n")
 53		if len(l) == 6 {
 54			l = l + "ff"
 55		}
 56		c, err := strconv.ParseUint(l, 16, 32)
 57		if err != nil {
 58			elog.Printf("error reading avatar color %d: %s", i, err)
 59			continue
 60		}
 61		avatarcolors[i][0] = byte(c >> 24 & 0xff)
 62		avatarcolors[i][1] = byte(c >> 16 & 0xff)
 63		avatarcolors[i][2] = byte(c >> 8 & 0xff)
 64		avatarcolors[i][3] = byte(c >> 0 & 0xff)
 65	}
 66}
 67
 68func genAvatar(name string) []byte {
 69	h := sha512.New()
 70	h.Write([]byte(name))
 71	s := h.Sum(nil)
 72	img := image.NewNRGBA(image.Rect(0, 0, 64, 64))
 73	for i := 0; i < 64; i++ {
 74		for j := 0; j < 64; j++ {
 75			p := i*img.Stride + j*4
 76			xx := i/16*16 + j/16
 77			x := s[xx]
 78			if x < 64 {
 79				img.Pix[p+0] = avatarcolors[0][0]
 80				img.Pix[p+1] = avatarcolors[0][1]
 81				img.Pix[p+2] = avatarcolors[0][2]
 82				img.Pix[p+3] = avatarcolors[0][3]
 83			} else if x < 128 {
 84				img.Pix[p+0] = avatarcolors[1][0]
 85				img.Pix[p+1] = avatarcolors[1][1]
 86				img.Pix[p+2] = avatarcolors[1][2]
 87				img.Pix[p+3] = avatarcolors[1][3]
 88			} else if x < 192 {
 89				img.Pix[p+0] = avatarcolors[2][0]
 90				img.Pix[p+1] = avatarcolors[2][1]
 91				img.Pix[p+2] = avatarcolors[2][2]
 92				img.Pix[p+3] = avatarcolors[2][3]
 93			} else {
 94				img.Pix[p+0] = avatarcolors[3][0]
 95				img.Pix[p+1] = avatarcolors[3][1]
 96				img.Pix[p+2] = avatarcolors[3][2]
 97				img.Pix[p+3] = avatarcolors[3][3]
 98			}
 99		}
100	}
101	var buf bytes.Buffer
102	png.Encode(&buf, img)
103	return buf.Bytes()
104}
105
106func showflag(writer http.ResponseWriter, req *http.Request) {
107	code := mux.Vars(req)["code"]
108	colors := strings.Split(code, ",")
109	numcolors := len(colors)
110	vert := false
111	if colors[0] == "vert" {
112		vert = true
113		colors = colors[1:]
114		numcolors--
115		if numcolors == 0 {
116			http.Error(writer, "bad flag", 400)
117			return
118		}
119	}
120	pixels := make([][4]byte, numcolors)
121	for i := 0; i < numcolors; i++ {
122		hex := colors[i]
123		if len(hex) == 3 {
124			hex = fmt.Sprintf("%c%c%c%c%c%c",
125				hex[0], hex[0], hex[1], hex[1], hex[2], hex[2])
126		}
127		c, _ := strconv.ParseUint(hex, 16, 32)
128		r := byte(c >> 16 & 0xff)
129		g := byte(c >> 8 & 0xff)
130		b := byte(c >> 0 & 0xff)
131		pixels[i][0] = r
132		pixels[i][1] = g
133		pixels[i][2] = b
134		pixels[i][3] = 255
135	}
136
137	h := 128
138	w := h * 3 / 2
139	img := image.NewRGBA(image.Rect(0, 0, w, h))
140	if vert {
141		for j := 0; j < w; j++ {
142			pix := pixels[j*numcolors/w][:]
143			for i := 0; i < h; i++ {
144				p := i*img.Stride + j*4
145				copy(img.Pix[p:], pix)
146			}
147		}
148	} else {
149		for i := 0; i < h; i++ {
150			pix := pixels[i*numcolors/h][:]
151			for j := 0; j < w; j++ {
152				p := i*img.Stride + j*4
153				copy(img.Pix[p:], pix)
154			}
155		}
156	}
157
158	writer.Header().Set("Cache-Control", "max-age="+somedays())
159	png.Encode(writer, img)
160}
161
162var re_flags = regexp.MustCompile("flag:[[:alnum:],]+")
163
164func fixupflags(h *Honk) []Emu {
165	var emus []Emu
166	count := 0
167	h.Noise = re_flags.ReplaceAllStringFunc(h.Noise, func(m string) string {
168		count++
169		var e Emu
170		e.Name = fmt.Sprintf(":flag%d:", count)
171		e.ID = fmt.Sprintf("https://%s/flag/%s", serverName, m[5:])
172		emus = append(emus, e)
173		return e.Name
174	})
175	return emus
176}
177
178func renderflags(h *Honk) {
179	h.Noise = re_flags.ReplaceAllStringFunc(h.Noise, func(m string) string {
180		code := m[5:]
181		src := fmt.Sprintf("https://%s/flag/%s", serverName, code)
182		return fmt.Sprintf(`<img class="emu" title="%s" src="%s">`, "flag", src)
183	})
184}