// route_setter.c
//
// Written by YOUR-NAME (YOUR-ZID)
// on TODAYS-DATE
//
// A linked list representation of a bouldering route.

#include <stdio.h>
#include <stdlib.h>

// Struct representing a hold in a climbing route
struct hold {
    int hold_id;
    int difficulty;
    struct hold *next;
};

// Your function prototypes
struct hold *append_hold(struct hold *route, int new_hold_id, int difficulty);
struct hold *insert_after_hold(struct hold *route, int hold_id, int new_hold_id, 
    int difficulty);
struct hold *remove_hold(struct hold *route, int hold_id);
struct hold *find_crux(struct hold *route);
int climber_progress(struct hold *route, int skill);

// Provided function prototypes
struct hold *create_hold(int hold_id, int difficulty);
void print_route(struct hold *route);
void free_route(struct hold *route);
void print_commands();
void command_loop();

// -----------------------------------------------------------------------------
//////////////// DO NOT CHANGE THE MAIN FUNCTION ///////////////////////////////

int main(void) {
    // Create a sample route with 4 holds
    printf("Welcome to Route Setter!\n");

    command_loop();
    return 0;
}

// -----------------------------------------------------------------------------
// YOUR FUNCTIONS
// -----------------------------------------------------------------------------

// Append a new hold to the end of the route.
struct hold *append_hold(struct hold *route, int new_hold_id, int difficulty) {
    // TODO: Implement this function
    return NULL;
}

// Insert a new hold after the hold with hold_id.
struct hold *insert_after_hold(struct hold *route, int hold_id, int new_hold_id, 
    int difficulty) {
    // TODO: Implement this function
    return NULL;
}

// Remove the hold with hold_id from the route.
struct hold *remove_hold(struct hold *route, int hold_id) {
    // TODO: Implement this function
    return NULL;
}

// Return a pointer to the hardest hold in the route.
struct hold *find_crux(struct hold *route) {
    // TODO: Implement this function
    return NULL;
}

// Return how many holds a climber can complete.
int climber_progress(struct hold *route, int skill) {
    // TODO: Implement this function
    return 0;
}

// -----------------------------------------------------------------------------
// PROVIDED FUNCTIONS
// -----------------------------------------------------------------------------
// DO NOT CHANGE ANY OF THE CODE BELOW HERE

// Creates a new hold and returns a pointer to it.
struct hold *create_hold(int hold_id, int difficulty) {
    struct hold *new_hold = malloc(sizeof(struct hold));

    new_hold->hold_id = hold_id;
    new_hold->difficulty = difficulty;
    new_hold->next = NULL;

    return new_hold;
}

// Prints the entire route, one hold per line.
void print_route(struct hold *route) {
    printf("==== Current Route ====\n");
    if (route == NULL) {
        printf("Route is empty.\n");
        return;
    }
    while (route != NULL) {
        printf("Hold %d (difficulty %d)\n", route->hold_id, route->difficulty);
        route = route->next;
    }
}

// Frees every hold in the route.
void free_route(struct hold *route) {
    while (route != NULL) {
        struct hold *next = route->next;
        free(route);
        route = next;
    }
}

// Print the available commands for the user.
void print_commands() {
    printf("Commands:\n");
    printf("  a <new_id> <difficulty> - append hold to the route\n");
    printf("  i <after_id> <new_id> <difficulty> - insert hold\n");
    printf("  r <hold_id>                         - remove hold\n");
    printf("  p                                   - print route\n");
    printf("  c <skill>                           - climber progress\n");
    printf("  x <skill>                           - find crux\n");
    printf("  q                                   - quit\n\n");
}

// Command loop for user input.
void command_loop() {
    char command;
    struct hold *route = NULL;

    while (scanf(" %c", &command) == 1 && command != 'q') {
        if (command == 'a') {
            int new_id;
            int difficulty;
            scanf("%d %d", &new_id, &difficulty);

            route = append_hold(route, new_id, difficulty);
        } else if (command == 'i') {
            int after_id;
            int new_id;
            int difficulty;
            scanf("%d %d %d", &after_id, &new_id, &difficulty);

            route = insert_after_hold(route, after_id, new_id, difficulty);
        } else if (command == 'p') {
            print_route(route);
        } else if (command == 'r') {
            int hold_id;
            scanf("%d", &hold_id);
            route = remove_hold(&route, hold_id);
        } else if (command == 'c') {
            int skill;
            scanf("%d", &skill);
            printf(
                "A climber with skill %d can climb %d holds before failing.\n",
                skill, climber_progress(route, skill)
            );
        } else if (command == 'x') {
            struct hold *crux = find_crux(route);
            if (crux != NULL) {
                printf(
                    "Crux hold is %d (difficulty %d)\n", 
                    crux->hold_id, crux->difficulty
                );
            } else {
                printf("No crux hold found.\n");
            }
        } else if (command == '?') {
            print_commands();
        }
    }

    free_route(route);
}