Trying to make a Wikipedia-style timeline in R

wiki_style_timeline.R

library(rvest)
library(tidyverse)
library(lubridate)
library(scales)
library(Cairo)
library(lubridate)

url <- "https://liquipedia.net/dota2/Team_Secret"
page <- read_html(url)

tbls <- html_nodes(page, ".roster") %>% 
  html_nodes("table") %>% 
  html_table(fill = TRUE)

tbls_df <- lapply(tbls, function(x) x[-1, 1:5])
tbls_df <- lapply(tbls_df, function(x) {colnames(x) = c("id", "name", "position", "join_date",
                                                        "leave_date"); x})
tbl <- bind_rows(tbls_df) %>% 
  mutate(joined = ymd(substr(join_date, 12, 21)),
         left = ymd(substr(leave_date, 13, 22))) %>% 
  select(-c(join_date, leave_date)) %>% 
  filter(name != 'distiled')

tbl$position <- ifelse(tbl$position %in% c("1", "1 (Sub)"), 1,
                       ifelse(tbl$position %in% c("1/2", "2"), 2,
                              ifelse(tbl$position %in% c("3"), 3,
                                     ifelse(tbl$position %in% c("4", "4 (Sub)", "4/5"), 4,
                                            ifelse(tbl$position %in% c("5", "5 (Sub)", "Sub"), 5, 5)))))

tbl$left <- ifelse(is.na(tbl$left), as.Date(18055, origin="1970-01-01"), tbl$left) %>% 
  as.Date(origin = "1970-01-01")

tbl_l <- tbl %>% 
  mutate(Start = as.Date(joined, "%Y-%m-%d"),
         End = as.Date(left, "%Y-%m-%d")) %>% 
  gather(date.type, task.date, -c(id, name, position)) %>% 
  arrange(date.type, task.date) %>% 
  mutate(Task = factor(id, levels = rev(unique(id)), ordered = TRUE)) %>% 
  filter(name != c('distiled', "Solitude"))

timeline <- ggplot(tbl_l, aes(x = Task, y = task.date, colour = position)) +
  geom_line(size = 6) +
  guides(colour = guide_legend(title = NULL)) +
  labs(x = NULL, y = NULL) +
  coord_flip() +
  scale_y_date() +
  theme(axis.text.x = element_text(angle = 45, hjust = 1))

timeline