#include "repl_history.h"
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <readline/history.h>

RavaREPLHistory_t* rava_repl_history_create(size_t max_size) {
    RavaREPLHistory_t *history = malloc(sizeof(RavaREPLHistory_t));
    if (!history) return NULL;
    history->capacity = max_size;
    history->entries = calloc(max_size, sizeof(char*));
    if (!history->entries) {
        free(history);
        return NULL;
    }
    history->count = 0;
    history->position = 0;
    return history;
}

void rava_repl_history_destroy(RavaREPLHistory_t *history) {
    if (!history) return;
    for (size_t i = 0; i < history->count; i++) {
        free(history->entries[i]);
    }
    free(history->entries);
    free(history);
}

void rava_repl_history_add(RavaREPLHistory_t *history, const char *entry) {
    if (!history || !entry || strlen(entry) == 0) return;
    if (history->count > 0) {
        if (strcmp(history->entries[history->count - 1], entry) == 0) {
            return;
        }
    }
    if (history->count >= history->capacity) {
        free(history->entries[0]);
        memmove(history->entries, history->entries + 1, (history->capacity - 1) * sizeof(char*));
        history->count--;
    }
    history->entries[history->count++] = strdup(entry);
    history->position = history->count;
    add_history(entry);
}

const char* rava_repl_history_get(RavaREPLHistory_t *history, size_t index) {
    if (!history || index >= history->count) return NULL;
    return history->entries[index];
}

const char* rava_repl_history_prev(RavaREPLHistory_t *history) {
    if (!history || history->count == 0) return NULL;
    if (history->position > 0) {
        history->position--;
    }
    return history->entries[history->position];
}

const char* rava_repl_history_next(RavaREPLHistory_t *history) {
    if (!history || history->count == 0) return NULL;
    if (history->position < history->count - 1) {
        history->position++;
        return history->entries[history->position];
    }
    history->position = history->count;
    return NULL;
}

void rava_repl_history_reset_position(RavaREPLHistory_t *history) {
    if (!history) return;
    history->position = history->count;
}

bool rava_repl_history_save(RavaREPLHistory_t *history, const char *filename) {
    if (!history || !filename) return false;
    FILE *f = fopen(filename, "w");
    if (!f) return false;
    for (size_t i = 0; i < history->count; i++) {
        fprintf(f, "%s\n", history->entries[i]);
    }
    fclose(f);
    return true;
}

bool rava_repl_history_load(RavaREPLHistory_t *history, const char *filename) {
    if (!history || !filename) return false;
    FILE *f = fopen(filename, "r");
    if (!f) return false;
    char line[RAVA_REPL_MAX_INPUT];
    while (fgets(line, sizeof(line), f)) {
        size_t len = strlen(line);
        if (len > 0 && line[len - 1] == '\n') {
            line[len - 1] = '\0';
        }
        if (strlen(line) > 0) {
            rava_repl_history_add(history, line);
        }
    }
    fclose(f);
    return true;
}