emailler/apps/email.c

426 lines
9.5 KiB
C

/////////////////////////////////////////////////////////////////
// Simple Email User Agent
// Handles INBOX in the format created by POP65
// Bobbi June 2020
/////////////////////////////////////////////////////////////////
// TODO:
// - Saving updated email status -> EMAIL.DB
// - Purging deleted emails
// - Switching folders
// - Moving & copying emails between folders
// - Email composition (reply and forward)
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <conio.h>
#include <string.h>
#define EMAIL_C
#include "email_common.h"
#define MSGS_PER_PAGE 20 // Number of messages shown on summary screen
#define SCROLLBACK 25*80 // How many bytes to go back when paging up
char filename[80];
FILE *fp;
struct emailhdrs *headers;
uint16_t selection, prevselection;
uint16_t num_msgs; // Number of messages shown in current page
uint16_t total_msgs; // Total number of message in mailbox
uint16_t first_msg; // Message number of first message on current page
/*
* Keypress before quit
*/
void confirm_exit(void) {
printf("\nPress any key ");
cgetc();
exit(0);
}
/*
* Called for all non IP65 errors
*/
void error_exit() {
confirm_exit();
}
/*
* Read parms from POP65.CFG
*/
void readconfigfile(void) {
fp = fopen("POP65.CFG", "r");
if (!fp) {
puts("Can't open config file POP65.CFG");
error_exit();
}
fscanf(fp, "%s", cfg_server);
fscanf(fp, "%s", cfg_user);
fscanf(fp, "%s", cfg_pass);
fscanf(fp, "%s", cfg_spooldir);
fscanf(fp, "%s", cfg_inboxdir);
fclose(fp);
}
/*
* Free linked list rooted at headers
*/
void free_headers_list(void) {
struct emailhdrs *h = headers;
while (h) {
free(h);
h = h->next; // Not strictly legal, but will work
}
headers = NULL;
}
/*
* Read EMAIL.DB and populate linked list rooted at headers
* startnum - number of the first message to load (1 is the first)
*/
void read_email_db(uint16_t startnum) {
struct emailhdrs *curr = NULL, *prev = NULL;
uint16_t count = 0;
uint16_t l;
free_headers_list();
sprintf(filename, "%s/EMAIL.DB", cfg_inboxdir);
fp = fopen(filename, "rb");
if (!fp) {
printf("Can't open %s\n", filename);
error_exit();
}
if (fseek(fp, (startnum - 1) * (sizeof(struct emailhdrs) - 2), SEEK_SET)) {
printf("Can't seek in %s\n", filename);
error_exit();
}
total_msgs = num_msgs = 0;
while (1) {
curr = (struct emailhdrs*)malloc(sizeof(struct emailhdrs));
curr->next = NULL;
l = fread(curr, 1, sizeof(struct emailhdrs) - 2, fp);
++count;
if (l != sizeof(struct emailhdrs) - 2) {
free(curr);
fclose(fp);
return;
}
if (count < MSGS_PER_PAGE) {
if (!prev)
headers = curr;
else
prev->next = curr;
prev = curr;
++num_msgs;
}
++total_msgs;
}
}
/*
* Print a header field from char postion start to end,
* padding with spaces as needed
*/
void printfield(char *s, uint8_t start, uint8_t end) {
uint8_t i;
uint8_t l = strlen(s);
for (i = start; i < end; i++)
putchar(i < l ? s[i] : ' ');
}
/*
* Print one line summary of email headers for one message
*/
void print_one_email_summary(struct emailhdrs *h, uint8_t inverse) {
putchar(inverse ? 0xf : 0xe); // INVERSE or NORMAL
switch(h->status) {
case 'N':
putchar('*'); // New
break;
case 'R':
putchar(' '); // Read
break;
case 'D':
putchar('D'); // Deleted
break;
}
printf("%02d|", h->emailnum);
printfield(h->date, 0, 16);
putchar('|');
printfield(h->from, 0, 20);
putchar('|');
printfield(h->subject, 0, 38);
//putchar('\r');
putchar(0xe); // NORMAL
}
/*
* Get emailhdrs for nth email in list of headers
*/
struct emailhdrs *get_headers(uint16_t n) {
uint16_t i = 1;
struct emailhdrs *h = headers;
while (h && (i < n)) {
++i;
h = h->next;
}
return h;
}
/*
* Show email summary
*/
void email_summary(void) {
uint8_t i = 1;
struct emailhdrs *h = headers;
clrscr();
printf("%c%u messages, displaying %u-%u%c",
0x0f, total_msgs, first_msg, first_msg + num_msgs - 1, 0x0e);
printf("\n\n");
while (h) {
print_one_email_summary(h, (i == selection));
++i;
h = h->next;
}
putchar(0x19); // HOME
for (i = 0; i < 22; ++i)
putchar(0x0a); // CURSOR DOWN
printf("%cUp/K Prev | Down/J Next | SPACE/CR Read | D)elete | U)ndel | Q)uit%c", 0x0f, 0x0e);
}
/*
* Show email summary for nth email message in list of headers
*/
void email_summary_for(uint16_t n) {
struct emailhdrs *h = headers;
uint16_t j;
h = get_headers(n);
putchar(0x19); // HOME
for (j = 0; j < n + 1; ++j)
putchar(0x0a); // CURSOR DOWN
print_one_email_summary(h, (n == selection));
}
/*
* Move the highlight bar when user selects different message
*/
void update_highlighted(void) {
email_summary_for(prevselection);
email_summary_for(selection);
}
/*
* Display email with simple pager functionality
*/
void email_pager(void) {
uint32_t pos = 0;
struct emailhdrs *h = get_headers(selection);
uint8_t line, eof;
char c;
clrscr();
sprintf(filename, "%s/EMAIL.%u", cfg_inboxdir, h->emailnum);
fp = fopen(filename, "rb");
if (!fp) {
printf("Can't open %s\n", filename);
printf("[Press any key]");
cgetc();
return;
}
h->status = 'R'; // Mark email read
pos = h->skipbytes;
fseek(fp, pos, SEEK_SET); // Skip over headers
restart:
clrscr();
line = 6;
fputs("Date: ", stdout);
printfield(h->date, 0, 70);
fputs("\nFrom: ", stdout);
printfield(h->from, 0, 70);
fputs("\nTo: ", stdout);
printfield(h->to, 0, 70);
if (h->cc[0] != '\0') {
fputs("\nCC: ", stdout);
printfield(h->cc, 0, 70);
++line;
}
fputs("\nSubject: ", stdout);
printfield(h->subject, 0, 70);
fputs("\n\n", stdout);
while (1) {
c = fgetc(fp);
eof = feof(fp);
if (!eof) {
putchar(c);
++pos;
}
if (c == '\r') {
++line;
if (line == 22) {
putchar(0x0f); // INVERSE
printf("[%05lu] SPACE continue reading | B)ack | T)op | H)drs | Q)uit", pos);
putchar(0x0e); // NORMAL
retry1:
c = cgetc();
switch (c) {
case ' ':
break;
case 'B':
case 'b':
if (pos < h->skipbytes + (uint32_t)(SCROLLBACK)) {
pos = h->skipbytes;
fseek(fp, pos, SEEK_SET);
goto restart;
} else {
pos -= (uint32_t)(SCROLLBACK);
fseek(fp, pos, SEEK_SET);
}
break;
case 'T':
case 't':
pos = h->skipbytes;
fseek(fp, pos, SEEK_SET);
goto restart;
break;
case 'H':
case 'h':
pos = 0;
fseek(fp, pos, SEEK_SET);
goto restart;
break;
case 'Q':
case 'q':
fclose(fp);
return;
default:
putchar(7); // BELL
goto retry1;
}
clrscr();
line = 0;
}
} else if (eof) {
putchar(0x0f); // INVERSE
printf("[%05lu] *** END *** | B)ack | T)op | H)drs | Q)uit", pos);
putchar(0x0e); // NORMAL
retry2:
c = cgetc();
switch (c) {
case 'B':
case 'b':
if (pos < h->skipbytes + (uint32_t)(SCROLLBACK)) {
pos = h->skipbytes;
fseek(fp, pos, SEEK_SET);
goto restart;
} else {
pos -= (uint32_t)(SCROLLBACK);
fseek(fp, pos, SEEK_SET);
}
break;
case 'T':
case 't':
pos = h->skipbytes;
fseek(fp, pos, SEEK_SET);
goto restart;
break;
case 'H':
case 'h':
pos = 0;
fseek(fp, pos, SEEK_SET);
goto restart;
break;
case 'Q':
case 'q':
fclose(fp);
return;
default:
putchar(7); // BELL
goto retry2;
}
clrscr();
line = 0;
}
}
}
/*
* Keyboard handler
*/
void keyboard_hdlr(void) {
struct emailhdrs *h;
while (1) {
char c = cgetc();
switch (c) {
case 'k':
case 'K':
case 0xb: // UP-ARROW
if (selection > 1) {
prevselection = selection;
--selection;
update_highlighted();
} else if (first_msg > MSGS_PER_PAGE) {
first_msg -= MSGS_PER_PAGE;
read_email_db(first_msg);
selection = num_msgs;
email_summary();
}
break;
case 'j':
case 'J':
case 0xa: // DOWN-ARROW
if (selection < num_msgs) {
prevselection = selection;
++selection;
update_highlighted();
} else if (first_msg + selection + 1 < total_msgs) {
first_msg += MSGS_PER_PAGE;
read_email_db(first_msg);
selection = 1;
email_summary();
}
break;
case 0x0d: // RETURN
case ' ':
email_pager();
email_summary();
break;
case 'd':
case 'D':
h = get_headers(selection);
if (h)
h->status = 'D';
email_summary_for(selection);
break;
case 'u':
case 'U':
h = get_headers(selection);
if (h)
h->status = 'R';
email_summary_for(selection);
break;
case 'p':
case 'P':
// TODO: Purge deleted messages
break;
case 'q':
case 'Q':
clrscr();
exit(0);
default:
//printf("[%02x]", c);
putchar(7); // BELL
}
}
}
void main(void) {
videomode(VIDEOMODE_80COL);
readconfigfile();
first_msg = 1;
read_email_db(first_msg);
selection = 1;
email_summary();
keyboard_hdlr();
}