#include <stdio.h>
#include <string.h>
#include "btree.h"

struct user {
    char *first;
    char *last;
    int age;
};

int user_compare(const void *a, const void *b, void *udata) {
    const struct user *ua = a;
    const struct user *ub = b;
    int cmp = strcmp(ua->last, ub->last);
    if (cmp == 0) {
        cmp = strcmp(ua->first, ub->first);
    }
    return cmp;
}

bool user_iter(const void *a, void *udata) {
    const struct user *user = a;
    printf("%s %s (age=%d)\n", user->first, user->last, user->age);
    return true;
}

int main() {
    // create a new btree where each item is a `struct user`. 
    struct btree *tr = btree_new(sizeof(struct user), 0, user_compare, NULL);

    // load some users into the btree. Each set operation performas a copy of 
    // the data that is pointed to in the second argument.
    btree_set(tr, &(struct user){ .first="Dale", .last="Murphy", .age=44 });
    btree_set(tr, &(struct user){ .first="Roger", .last="Craig", .age=68 });
    btree_set(tr, &(struct user){ .first="Jane", .last="Murphy", .age=47 });

    struct user *user; 
    
    printf("\n-- get some users --\n");
    user = btree_get(tr, &(struct user){ .first="Jane", .last="Murphy" });
    printf("%s age=%d\n", user->first, user->age);

    user = btree_get(tr, &(struct user){ .first="Roger", .last="Craig" });
    printf("%s age=%d\n", user->first, user->age);

    user = btree_get(tr, &(struct user){ .first="Dale", .last="Murphy" });
    printf("%s age=%d\n", user->first, user->age);

    user = btree_get(tr, &(struct user){ .first="Tom", .last="Buffalo" });
    printf("%s\n", user?"exists":"not exists");


    printf("\n-- iterate over all users --\n");
    btree_ascend(tr, NULL, user_iter, NULL);

    printf("\n-- iterate beginning with last name `Murphy` --\n");
    btree_ascend(tr, &(struct user){.first="",.last="Murphy"}, user_iter, NULL);

    btree_free(tr);
}

// output:
// -- get some users --
// Jane age=47
// Roger age=68
// Dale age=44
// not exists
// 
// -- iterate over all users --
// Roger Craig (age=68)
// Dale Murphy (age=44)
// Jane Murphy (age=47)
// 
// -- iterate beginning with last name `Murphy` --
// Dale Murphy (age=44)
// Jane Murphy (age=47)