refactor(api): split MSN provider module

src/api/msn/mod.rs

@@ -0,0 +1,93 @@
+mod client;
+mod parse;
+mod symbols;
+
+use crate::api::MarketDataProvider;
+use crate::api::types::{Fundamentals, Interval, Ohlc, Period, Quote};
+use crate::error::IdxError;
+
+use client::MsnClient;
+use parse::{
+    ResampleInterval, parse_fundamentals, parse_history_with_verbose, parse_quote, resample_history,
+};
+
+pub(crate) use parse::{parse_fundamentals_from_str, parse_history_from_str, parse_quote_from_str};
+
+pub struct MsnProvider {
+    client: MsnClient,
+    verbose: bool,
+}
+
+impl MsnProvider {
+    pub fn new(verbose: bool) -> Self {
+        Self {
+            client: MsnClient::new(),
+            verbose,
+        }
+    }
+
+    fn chart_type_for_period(period: &Period) -> &'static str {
+        match period {
+            Period::OneDay => "1D1M",
+            Period::FiveDays | Period::OneMonth => "1M",
+            Period::ThreeMonths => "3M",
+            Period::SixMonths | Period::OneYear => "1Y",
+            Period::TwoYears => "3Y",
+            Period::FiveYears => "5Y",
+        }
+    }
+}
+
+impl MarketDataProvider for MsnProvider {
+    fn quote(&self, symbol: &str) -> Result<Quote, IdxError> {
+        let quotes = self.client.fetch_quotes(symbol)?;
+        parse_quote(symbol, &quotes)
+    }
+
+    fn fundamentals(&self, symbol: &str) -> Result<Fundamentals, IdxError> {
+        let ratios = self.client.fetch_key_ratios(symbol)?;
+        let quote = self
+            .client
+            .fetch_quotes(symbol)
+            .map_err(|e| {
+                if self.verbose {
+                    eprintln!("warning: quote fetch for fundamentals failed: {e}");
+                }
+                e
+            })
+            .ok()
+            .and_then(|quotes| quotes.into_iter().next());
+        parse_fundamentals(&ratios, quote.as_ref())
+    }
+
+    fn history(
+        &self,
+        symbol: &str,
+        period: &Period,
+        interval: &Interval,
+    ) -> Result<Vec<Ohlc>, IdxError> {
+        let charts = self
+            .client
+            .fetch_charts(symbol, Self::chart_type_for_period(period))?;
+        let rows = parse_history_with_verbose(period, &charts, self.verbose)?;
+        Ok(match interval {
+            Interval::Day => rows,
+            Interval::Week => resample_history(&rows, ResampleInterval::Week),
+            Interval::Month => resample_history(&rows, ResampleInterval::Month),
+        })
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::MsnProvider;
+    use crate::api::types::Period;
+
+    #[test]
+    fn maps_periods_to_supported_chart_types() {
+        assert_eq!(MsnProvider::chart_type_for_period(&Period::OneDay), "1D1M");
+        assert_eq!(MsnProvider::chart_type_for_period(&Period::SixMonths), "1Y");
+        assert_eq!(MsnProvider::chart_type_for_period(&Period::TwoYears), "3Y");
+        assert_eq!(MsnProvider::chart_type_for_period(&Period::FiveYears), "5Y");
+    }
+}