/*
 * I/O and support routines.
 *
 * SPDX-FileCopyrightText: (C) 1977, 2005 by Will Crowther and Don Woods
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include <ctype.h>
#include <editline/readline.h>
#include <inttypes.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <unistd.h>

#include "advent.h"
#include "dungeon.h"

static void *xcalloc(size_t size) {
	void *ptr = calloc(size, 1);
	if (ptr == NULL) {
		// LCOV_EXCL_START
		// exclude from coverage analysis because we can't simulate an
		// out of memory error in testing
		fprintf(stderr, "Out of memory!\n");
		exit(EXIT_FAILURE);
		// LCOV_EXCL_STOP
	}
	return (ptr);
}

/*  I/O routines (speak, pspeak, rspeak, sspeak, get_input, yes) */

static void vspeak(const char *msg, bool blank, va_list ap) {
	/* Engine for various speak functions */
	// Do nothing if we got a null pointer.
	if (msg == NULL) {
		return;
	}

	// Do nothing if we got an empty string.
	if (strlen(msg) == 0) {
		return;
	}

	if (blank == true) {
		printf("\n");
	}

	int msglen = strlen(msg);

	// Rendered string
	ssize_t size = 2000; /* msglen > 50 ? msglen*2 : 100; */
	char *rendered = xcalloc(size);
	char *renderp = rendered;

	// Handle format specifiers (including the custom %S) by
	// adjusting the parameter accordingly, and replacing the
	// specifier with %s.
	bool pluralize = false;
	for (int i = 0; i < msglen; i++) {
		if (msg[i] != '%') {
			/* Ugh.  Least obtrusive way to deal with artifacts "on
			 * the floor" being dropped outside of both cave and
			 * building. */
			if (strncmp(msg + i, "floor", 5) == 0 &&
			    strchr(" .", msg[i + 5]) && !INSIDE(game.loc)) {
				strcpy(renderp, "ground");
				renderp += 6;
				i += 4;
				size -= 5;
			} else {
				*renderp++ = msg[i];
				size--;
			}
		} else {
			i++;
			// Integer specifier.
			if (msg[i] == 'd') {
				int32_t arg = va_arg(ap, int32_t);
				int ret =
				    snprintf(renderp, size, "%" PRId32, arg);
				if (ret < size) {
					renderp += ret;
					size -= ret;
				}
				pluralize = (arg != 1);
			}

			// Unmodified string specifier.
			if (msg[i] == 's') {
				char *arg = va_arg(ap, char *);
				strncat(renderp, arg, size - 1);
				size_t len = strlen(renderp);
				renderp += len;
				size -= len;
			}

			// Singular/plural specifier.
			if (msg[i] == 'S') {
				// look at the *previous* numeric parameter
				if (pluralize) {
					*renderp++ = 's';
					size--;
				}
			}

			// LCOV_EXCL_START - doesn't occur in test suite.
			/* Version specifier */
			if (msg[i] == 'V') {
				strcpy(renderp, VERSION);
				size_t len = strlen(VERSION);
				renderp += len;
				size -= len;
			}
			// LCOV_EXCL_STOP
		}
	}
	*renderp = 0;

	// Print the message.
	printf("%s\n", rendered);

	free(rendered);
}

void speak(const char *msg, ...) {
	/* speak a specified string */
	va_list ap;
	va_start(ap, msg);
	vspeak(msg, true, ap);
	va_end(ap);
}

void sspeak(const int msg, ...) {
	/* Speak a message from the arbitrary-messages list */
	va_list ap;
	va_start(ap, msg);
	fputc('\n', stdout);
	vprintf(arbitrary_messages[msg], ap);
	fputc('\n', stdout);
	va_end(ap);
}

void pspeak(vocab_t msg, enum speaktype mode, bool blank, int skip, ...) {
	/* Find the skip+1st message from msg and print it.  Modes are:
	 * feel = for inventory, what you can touch
	 * look = the full description for the state the object is in
	 * listen = the sound for the state the object is in
	 * study = text on the object. */
	va_list ap;
	va_start(ap, skip);
	switch (mode) {
	case touch:
		vspeak(objects[msg].inventory, blank, ap);
		break;
	case look:
		vspeak(objects[msg].descriptions[skip], blank, ap);
		break;
	case hear:
		vspeak(objects[msg].sounds[skip], blank, ap);
		break;
	case study:
		vspeak(objects[msg].texts[skip], blank, ap);
		break;
	case change:
		vspeak(objects[msg].changes[skip], blank, ap);
		break;
	}
	va_end(ap);
}

void rspeak(vocab_t i, ...) {
	/* Print the i-th "random" message (section 6 of database). */
	va_list ap;
	va_start(ap, i);
	vspeak(arbitrary_messages[i], true, ap);
	va_end(ap);
}

void echo_input(FILE *destination, const char *input_prompt,
                const char *input) {
	size_t len = strlen(input_prompt) + strlen(input) + 1;
	char *prompt_and_input = (char *)xcalloc(len);
	strcpy(prompt_and_input, input_prompt);
	strcat(prompt_and_input, input);
	fprintf(destination, "%s\n", prompt_and_input);
	free(prompt_and_input);
}

static int word_count(char *str) {
	char delims[] = " \t";
	int count = 0;
	int inblanks = true;

	for (char *s = str; *s; s++)
		if (inblanks) {
			if (strchr(delims, *s) == 0) {
				++count;
				inblanks = false;
			}
		} else {
			if (strchr(delims, *s) != 0) {
				inblanks = true;
			}
		}

	return (count);
}

static char *get_input(void) {
	// Set up the prompt
	char input_prompt[] = PROMPT;
	if (!settings.prompt)
		input_prompt[0] = '\0';

	// Print a blank line
	printf("\n");

	char *input;
	for (;;) {
		input = myreadline(input_prompt);

		if (input == NULL) // Got EOF; return with it.
			return (input);
		if (input[0] == '#') { // Ignore comments.
			free(input);
			continue;
		}
		// We have a 'normal' line; leave the loop.
		break;
	}

	// Strip trailing newlines from the input
	input[strcspn(input, "\n")] = 0;

	add_history(input);

	if (!isatty(0))
		echo_input(stdout, input_prompt, input);

	if (settings.logfp)
		echo_input(settings.logfp, "", input);

	return (input);
}

bool silent_yes_or_no(void) {
	bool outcome = false;

	for (;;) {
		char *reply = get_input();
		if (reply == NULL) {
			// LCOV_EXCL_START
			// Should be unreachable. Reply should never be NULL
			free(reply);
			exit(EXIT_SUCCESS);
			// LCOV_EXCL_STOP
		}
		if (strlen(reply) == 0) {
			free(reply);
			rspeak(PLEASE_ANSWER);
			continue;
		}

		char *firstword = (char *)xcalloc(strlen(reply) + 1);
		sscanf(reply, "%s", firstword);

		free(reply);

		for (int i = 0; i < (int)strlen(firstword); ++i)
			firstword[i] = tolower(firstword[i]);

		int yes = strncmp("yes", firstword, sizeof("yes") - 1);
		int y = strncmp("y", firstword, sizeof("y") - 1);
		int no = strncmp("no", firstword, sizeof("no") - 1);
		int n = strncmp("n", firstword, sizeof("n") - 1);

		free(firstword);

		if (yes == 0 || y == 0) {
			outcome = true;
			break;
		} else if (no == 0 || n == 0) {
			outcome = false;
			break;
		} else
			rspeak(PLEASE_ANSWER);
	}
	return (outcome);
}

bool yes_or_no(const char *question, const char *yes_response,
               const char *no_response) {
	/*  Print message X, wait for yes/no answer.  If yes, print Y and return
	 * true; if no, print Z and return false. */
	bool outcome = false;

	for (;;) {
		speak(question);

		char *reply = get_input();
		if (reply == NULL) {
			// LCOV_EXCL_START
			// Should be unreachable. Reply should never be NULL
			free(reply);
			exit(EXIT_SUCCESS);
			// LCOV_EXCL_STOP
		}

		if (strlen(reply) == 0) {
			free(reply);
			rspeak(PLEASE_ANSWER);
			continue;
		}

		char *firstword = (char *)xcalloc(strlen(reply) + 1);
		sscanf(reply, "%s", firstword);

		free(reply);

		for (int i = 0; i < (int)strlen(firstword); ++i) {
			firstword[i] = tolower(firstword[i]);
		}

		int yes = strncmp("yes", firstword, sizeof("yes") - 1);
		int y = strncmp("y", firstword, sizeof("y") - 1);
		int no = strncmp("no", firstword, sizeof("no") - 1);
		int n = strncmp("n", firstword, sizeof("n") - 1);

		free(firstword);

		if (yes == 0 || y == 0) {
			speak(yes_response);
			outcome = true;
			break;
		} else if (no == 0 || n == 0) {
			speak(no_response);
			outcome = false;
			break;
		} else
			rspeak(PLEASE_ANSWER);
	}

	return (outcome);
}

/*  Data structure routines */

static int get_motion_vocab_id(const char *word) {
	// Return the first motion number that has 'word' as one of its words.
	for (int i = 0; i < NMOTIONS; ++i) {
		for (int j = 0; j < motions[i].words.n; ++j) {
			if (strncasecmp(word, motions[i].words.strs[j],
			                TOKLEN) == 0 &&
			    (strlen(word) > 1 ||
			     strchr(ignore, word[0]) == NULL ||
			     !settings.oldstyle))
				return (i);
		}
	}
	// If execution reaches here, we didn't find the word.
	return (WORD_NOT_FOUND);
}

static int get_object_vocab_id(const char *word) {
	// Return the first object number that has 'word' as one of its words.
	for (int i = 0; i < NOBJECTS + 1;
	     ++i) { // FIXME: the + 1 should go when 1-indexing for objects is
		    // removed
		for (int j = 0; j < objects[i].words.n; ++j) {
			if (strncasecmp(word, objects[i].words.strs[j],
			                TOKLEN) == 0)
				return (i);
		}
	}
	// If execution reaches here, we didn't find the word.
	return (WORD_NOT_FOUND);
}

static int get_action_vocab_id(const char *word) {
	// Return the first motion number that has 'word' as one of its words.
	for (int i = 0; i < NACTIONS; ++i) {
		for (int j = 0; j < actions[i].words.n; ++j) {
			if (strncasecmp(word, actions[i].words.strs[j],
			                TOKLEN) == 0 &&
			    (strlen(word) > 1 ||
			     strchr(ignore, word[0]) == NULL ||
			     !settings.oldstyle)) {
				return (i);
			}
		}
	}
	// If execution reaches here, we didn't find the word.
	return (WORD_NOT_FOUND);
}

static bool is_valid_int(const char *str) {
	/* Returns true if the string passed in is represents a valid integer,
	 * that could then be parsed by atoi() */
	// Handle negative number
	if (*str == '-') {
		++str;
	}

	// Handle empty string or just "-". Should never reach this
	// point, because this is only used with transitive verbs.
	if (!*str) {
		return false; // LCOV_EXCL_LINE
	}

	// Check for non-digit chars in the rest of the string.
	while (*str) {
		if (!isdigit(*str)) {
			return false;
		} else {
			++str;
		}
	}

	return true;
}

static void get_vocab_metadata(const char *word, vocab_t *id,
                               word_type_t *type) {
	/* Check for an empty string */
	if (strncmp(word, "", sizeof("")) == 0) {
		*id = WORD_EMPTY;
		*type = NO_WORD_TYPE;
		return;
	}

	vocab_t ref_num;

	ref_num = get_motion_vocab_id(word);
	// Second conjunct is because the magic-word placeholder is a bit
	// special
	if (ref_num != WORD_NOT_FOUND) {
		*id = ref_num;
		*type = MOTION;
		return;
	}

	ref_num = get_object_vocab_id(word);
	if (ref_num != WORD_NOT_FOUND) {
		*id = ref_num;
		*type = OBJECT;
		return;
	}

	ref_num = get_action_vocab_id(word);
	if (ref_num != WORD_NOT_FOUND && ref_num != PART) {
		*id = ref_num;
		*type = ACTION;
		return;
	}

	// Check for the reservoir magic word.
	if (strcasecmp(word, game.zzword) == 0) {
		*id = PART;
		*type = ACTION;
		return;
	}

	// Check words that are actually numbers.
	if (is_valid_int(word)) {
		*id = WORD_EMPTY;
		*type = NUMERIC;
		return;
	}

	*id = WORD_NOT_FOUND;
	*type = NO_WORD_TYPE;
	return;
}

static void tokenize(char *raw, command_t *cmd) {
	/*
	 * Be careful about modifying this. We do not want to nuke the
	 * the speech part or ID from the previous turn.
	 */
	memset(&cmd->word[0].raw, '\0', sizeof(cmd->word[0].raw));
	memset(&cmd->word[1].raw, '\0', sizeof(cmd->word[1].raw));

	/* Bound prefix on the %s would be needed to prevent buffer
	 * overflow.  but we shortstop this more simply by making each
	 * raw-input buffer as int as the entire input buffer. */
	sscanf(raw, "%s%s", cmd->word[0].raw, cmd->word[1].raw);

	/* (ESR) In oldstyle mode, simulate the uppercasing and truncating
	 * effect on raw tokens of packing them into sixbit characters, 5
	 * to a 32-bit word.  This is something the FORTRAN version did
	 * because archaic FORTRAN had no string types.  Don Wood's
	 * mechanical translation of 2.5 to C retained the packing and
	 * thus this misfeature.
	 *
	 * It's philosophically questionable whether this is the right
	 * thing to do even in oldstyle mode.  On one hand, the text
	 * mangling was not authorial intent, but a result of limitations
	 * in their tools. On the other, not simulating this misbehavior
	 * goes against the goal of making oldstyle as accurate as
	 * possible an emulation of the original UI.
	 */
	if (settings.oldstyle) {
		cmd->word[0].raw[TOKLEN + TOKLEN] =
		    cmd->word[1].raw[TOKLEN + TOKLEN] = '\0';
		for (size_t i = 0; i < strlen(cmd->word[0].raw); i++) {
			cmd->word[0].raw[i] = toupper(cmd->word[0].raw[i]);
		}
		for (size_t i = 0; i < strlen(cmd->word[1].raw); i++) {
			cmd->word[1].raw[i] = toupper(cmd->word[1].raw[i]);
		}
	}

	/* populate command with parsed vocabulary metadata */
	get_vocab_metadata(cmd->word[0].raw, &(cmd->word[0].id),
	                   &(cmd->word[0].type));
	get_vocab_metadata(cmd->word[1].raw, &(cmd->word[1].id),
	                   &(cmd->word[1].type));
	cmd->state = TOKENIZED;
}

bool get_command_input(command_t *command) {
	/* Get user input on stdin, parse and map to command */
	char inputbuf[LINESIZE];
	char *input;

	for (;;) {
		input = get_input();
		if (input == NULL)
			return false;
		if (word_count(input) > 2) {
			rspeak(TWO_WORDS);
			free(input);
			continue;
		}
		if (strcmp(input, "") != 0) {
			break;
		}
		free(input);
	}

	strncpy(inputbuf, input, LINESIZE - 1);
	free(input);

	tokenize(inputbuf, command);

#ifdef GDEBUG
	/* Needs to stay synced with enum word_type_t */
	const char *types[] = {"NO_WORD_TYPE", "MOTION", "OBJECT", "ACTION",
	                       "NUMERIC"};
	/* needs to stay synced with enum speechpart */
	const char *roles[] = {"unknown", "intransitive", "transitive"};
	printf(
	    "Command: role = %s type1 = %s, id1 = %d, type2 = %s, id2 = %d\n",
	    roles[command->part], types[command->word[0].type],
	    command->word[0].id, types[command->word[1].type],
	    command->word[1].id);
#endif

	command->state = GIVEN;
	return true;
}

void clear_command(command_t *cmd) {
	/* Resets the state of the command to empty */
	cmd->verb = ACT_NULL;
	cmd->part = unknown;
	game.oldobj = cmd->obj;
	cmd->obj = NO_OBJECT;
	cmd->state = EMPTY;
}

void juggle(obj_t object) {
	/*  Juggle an object by picking it up and putting it down again, the
	 * purpose being to get the object to the front of the chain of things
	 * at its loc. */
	loc_t i, j;

	i = game.objects[object].place;
	j = game.objects[object].fixed;
	move(object, i);
	move(object + NOBJECTS, j);
}

void move(obj_t object, loc_t where) {
	/*  Place any object anywhere by picking it up and dropping it.  May
	 *  already be toting, in which case the carry is a no-op.  Mustn't
	 *  pick up objects which are not at any loc, since carry wants to
	 *  remove objects from game atloc chains. */
	loc_t from;

	if (object > NOBJECTS) {
		from = game.objects[object - NOBJECTS].fixed;
	} else {
		from = game.objects[object].place;
	}
	/* (ESR) Used to check for !SPECIAL(from). I *think* that was wrong...
	 */
	if (from != LOC_NOWHERE && from != CARRIED) {
		carry(object, from);
	}
	drop(object, where);
}

void put(obj_t object, loc_t where, int pval) {
	/*  put() is the same as move(), except it returns a value used to set
	 * up the negated game.prop values for the repository objects. */
	move(object, where);
	/* (ESR) Read this in combination with the macro defintions in advebt.h.
	 */
	game.objects[object].prop = PROP_STASHIFY(pval);
#ifdef PROP_SET_SEEN
	PROP_SET_SEEN(object);
#endif
}

void carry(obj_t object, loc_t where) {
	/*  Start toting an object, removing it from the list of things at its
	 * former location.  Incr holdng unless it was already being toted.  If
	 * object>NOBJECTS (moving "fixed" second loc), don't change game.place
	 * or game.holdng. */
	int temp;

	if (object <= NOBJECTS) {
		if (game.objects[object].place == CARRIED) {
			return;
		}
		game.objects[object].place = CARRIED;

		/*
		 * Without this conditional your inventory is overcounted
		 * when you pick up the bird while it's caged. This fixes
		 * a cosmetic bug in the original.
		 *
		 * Possibly this check should be skipped whwn oldstyle is on.
		 */
		if (object != BIRD)
			++game.holdng;
	}
	if (game.locs[where].atloc == object) {
		game.locs[where].atloc = game.link[object];
		return;
	}
	temp = game.locs[where].atloc;
	while (game.link[temp] != object) {
		temp = game.link[temp];
	}
	game.link[temp] = game.link[object];
}

void drop(obj_t object, loc_t where) {
	/*  Place an object at a given loc, prefixing it onto the game atloc
	 * list.  Decr game.holdng if the object was being toted. No state
	 * change on the object. */
	if (object > NOBJECTS) {
		game.objects[object - NOBJECTS].fixed = where;
	} else {
		if (game.objects[object].place == CARRIED)
			if (object != BIRD)
				/* The bird has to be weightless.  This ugly
				 * hack (and the corresponding code in the carry
				 * function) brought to you by the fact that
				 * when the bird is caged, we need to be able to
				 * either 'take bird' or 'take cage' and have
				 * the right thing happen.
				 */
				--game.holdng;
		game.objects[object].place = where;
	}
	if (where == LOC_NOWHERE || where == CARRIED) {
		return;
	}
	game.link[object] = game.locs[where].atloc;
	game.locs[where].atloc = object;
}

int atdwrf(loc_t where) {
	/*  Return the index of first dwarf at the given location, zero if no
	 * dwarf is there (or if dwarves not active yet), -1 if all dwarves are
	 * dead.  Ignore the pirate (6th dwarf). */
	int at;

	at = 0;
	if (game.dflag < 2) {
		return at;
	}
	at = -1;
	for (int i = 1; i <= NDWARVES - 1; i++) {
		if (game.dwarves[i].loc == where) {
			return i;
		}
		if (game.dwarves[i].loc != 0) {
			at = 0;
		}
	}
	return at;
}

/*  Utility routines (setbit, tstbit, set_seed, get_next_lcg_value,
 *  randrange) */

int setbit(int bit) {
	/*  Returns 2**bit for use in constructing bit-masks. */
	return (1L << bit);
}

bool tstbit(int mask, int bit) {
	/*  Returns true if the specified bit is set in the mask. */
	return (mask & (1 << bit)) != 0;
}

void set_seed(int32_t seedval) {
	/* Set the LCG1 seed */
	game.lcg_x = seedval % LCG_M;
	if (game.lcg_x < 0) {
		game.lcg_x = LCG_M + game.lcg_x;
	}
	// once seed is set, we need to generate the Z`ZZZ word
	for (int i = 0; i < 5; ++i) {
		game.zzword[i] = 'A' + randrange(26);
	}
	game.zzword[1] = '\''; // force second char to apostrophe
	game.zzword[5] = '\0';
}

static int32_t get_next_lcg_value(void) {
	/* Return the LCG's current value, and then iterate it. */
	int32_t old_x = game.lcg_x;
	game.lcg_x = (LCG_A * game.lcg_x + LCG_C) % LCG_M;
	if (settings.debug) {
		printf("# random %d\n", old_x); // LCOV_EXCL_LINE
	}
	return old_x;
}

int32_t randrange(int32_t range) {
	/* Return a random integer from [0, range). */
	return range * get_next_lcg_value() / LCG_M;
}

// LCOV_EXCL_START
void bug(enum bugtype num, const char *error_string) {
	fprintf(stderr, "Fatal error %d, %s.\n", num, error_string);
	exit(EXIT_FAILURE);
}
// LCOV_EXCL_STOP

void state_change(obj_t obj, int state) {
	/* Object must have a change-message list for this to be useful; only
	 * some do */
	game.objects[obj].prop = state;
	pspeak(obj, change, true, state);
}

/* end */