67 lines
1.1 KiB
Go
67 lines
1.1 KiB
Go
package utils
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import (
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"crypto/rand"
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"encoding/hex"
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"fmt"
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"github.com/dslipak/pdf"
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"io"
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)
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func GenerateSessionId(length int) string {
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bytes := make([]byte, length) // 16 bytes = 128 bits
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_, err := rand.Read(bytes)
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if err != nil {
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panic("failed to generate session ID")
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}
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return hex.EncodeToString(bytes)
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}
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func GenerateToken() string {
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return GenerateSessionId(16)
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}
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const match = "/Page\x00"
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// Pages reads the given io.ByteReader until EOF is reached, returning the
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// number of pages encountered.
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func Pages(reader io.ByteReader) (pages int) {
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i := 0
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for {
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b, err := reader.ReadByte()
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if err != nil {
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fmt.Println(err)
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return
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}
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check:
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switch match[i] {
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case 0:
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if !(b >= 'A' && b <= 'Z' || b >= 'a' && b <= 'z') {
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pages++
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}
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i = 0
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goto check
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case b:
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i++
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default:
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i = 0
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}
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}
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}
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// PagesAtPath opens a PDF file at the given file path, returning the number
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// of pages found.
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func CountPagesAtPath(path string) (pages int) {
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r, err := pdf.Open(path)
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if err != nil {
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fmt.Println("LOL")
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fmt.Println(err)
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return 0
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}
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pages = r.NumPage()
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return
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}
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