---
title: "Lab 6: San Francisco Airbnb Listings"
output: 
  flexdashboard::flex_dashboard:
    theme: journal
    social: menu
    source_code: embed
---


```{r setup, include=FALSE}
library(tidyverse)
library(sf)
library(plotly)
library(leaflet)
library(flexdashboard)

# load data
airbnb <- read_csv('/Users/joyceliu/Desktop/School/11.218/Lab 3/listingsSF.csv.gz') %>% 
  mutate(host_is_superhost = ifelse(!host_is_superhost | is.na(host_is_superhost), "Non-Superhost", "Superhost"))
b <- st_read('SF_Find_Neighborhoods_20251028.geojson')

# define a color palette
pal <- colorFactor(palette = c('salmon', 'gold', 'skyblue', 'orchid1'), domain = airbnb$room_type)

# define popup format
p_fmt <- paste0("<b>Name: </b>", airbnb$name, "<br>",
         "<b>Host Name: </b>", airbnb$host_name,"<br>",
         "<b>Nightly price: </b>", airbnb$price, "<br>")

# process data about hosts
hosts <- airbnb %>% 
  select(host_id, host_name, host_response_time, host_response_rate, host_is_superhost) %>% 
  mutate(host_response_rate = ifelse(host_response_rate == "N/A", "0", host_response_rate),
         host_response_rate = as.numeric(str_replace_all(host_response_rate, "%", ""))) %>% 
  filter(!(host_response_time %in% c(NA, "N/A")))

hosts$host_response_time <- factor(hosts$host_response_time, levels = c("a few days or more",
                                                                        "within a day",
                                                                        "within a few hours",
                                                                        "within an hour"))

# process data about listing size
price_beds <- airbnb %>% 
  select(room_type, price, beds, bedrooms) %>% 
  mutate(price = as.numeric(str_replace_all(price, "[$,]", ""))) %>% 
  filter(price < 7500)
```

Column {data-width=450}
-------------------------------------

### Chart A: Airbnb Locations in San Francisco

```{r}
leaflet() %>% 
  addProviderTiles(providers$CartoDB.Positron) %>% 
  setView(lng = -122.42, lat = 37.76, zoom = 12.4) %>%
  addCircles(data = airbnb,
             fillColor = ~pal(room_type),
             fillOpacity = 20,
             stroke = F,
             radius = 10,
             popup = p_fmt,
             group = "Airbnb Listings") %>% 
  addPolygons(data = b,
              color = "blue",
              fill = F,
              weight = 1,
              group = "Neighborhood Boundary") %>% 
  addLegend(position = "topright",
            pal = pal,
            values = airbnb$room_type,
            title = "Room Type") %>% 
  addLayersControl(overlayGroups = c("Airbnb Listings",
                                     "Neighborhood Boundary"))
```



Column {data-width=650}
-------------------------------------

### Chart B: Response Habits of Superhosts and Non-Superhosts

```{r}
hosts %>% ggplot(aes(x = host_response_rate, fill = host_is_superhost)) +
  geom_histogram(aes(y = after_stat(density))) + 
  facet_wrap(~host_is_superhost + host_response_time, 
             nrow = 2, ncol = 4,
             labeller = labeller(
               host_is_superhost = function(x) "",
               host_response_time = function(x) str_wrap(x, width = 10)
               )
             ) +
  scale_x_continuous(labels = scales::percent_format(scale = 1)) +
  scale_y_continuous(labels = scales::percent_format()) +
  scale_fill_manual(values = c("darkorchid1", "palevioletred2"),
                    name = "") +
  labs(x = "Host response rate", y = "Density") +
  theme(strip.background = element_blank(),
        axis.text.x = element_text(angle = 90, hjust = 1))
```

### Chart C: Price and Size of Airbnb Listings

```{r}
#| warning: false
#| message: false
price_beds %>% ggplot(aes(x = bedrooms, y = price, col = room_type)) +
  geom_point(size = 1) +
  geom_smooth(method = "lm", size = 0.5, se = F, fullrange = T) +
  scale_color_manual(name = "Room type",
                     values = c('salmon', 'gold', 'skyblue', 'orchid1')) +
  scale_y_continuous(labels = scales::dollar_format()) +
  labs(x = "Number of bedrooms",
       y = "Price per day")
```