Rework reading from device and clean up.

src/mapping/map.rs

@@ -0,0 +1,207 @@
+use std::fs::File;
+
+use super::{Cluster, Domain, Stage};
+
+use ron::de::from_reader;
+use ron::error::SpannedError;
+use serde::{Deserialize, Serialize};
+
+#[derive(Clone, Debug, Serialize, Deserialize, PartialEq)]
+pub struct MapFile {
+    pub sector_size: u16,
+    pub domain: Domain,
+    pub map: Vec<Cluster>,
+}
+
+impl TryFrom<File> for MapFile {
+    type Error = SpannedError;
+
+    fn try_from(file: File) -> Result<Self, Self::Error> {
+        from_reader(file)
+    }
+}
+
+impl Default for MapFile {
+    fn default() -> Self {
+        MapFile {
+            sector_size: crate::FB_SECTOR_SIZE,
+            domain: Domain::default(),
+            map: vec![Cluster {
+                domain: Domain::default(),
+                stage: Stage::Untested,
+            }],
+        }
+    }
+}
+
+impl MapFile {
+    pub fn new(sector_size: u16) -> Self {
+        MapFile::default().set_sector_size(sector_size).to_owned()
+    }
+
+    pub fn set_sector_size(&mut self, sector_size: u16) -> &mut Self {
+        self.sector_size = sector_size;
+        self
+    }
+
+    /// Recalculate cluster mappings.
+    pub fn update(&mut self, new_cluster: Cluster) -> &mut Self {
+        let mut new_map: Vec<Cluster> = vec![Cluster::from(new_cluster.to_owned())];
+
+        for map_cluster in self.map.iter() {
+            let mut map_cluster = *map_cluster;
+
+            // If new_cluster doesn't start ahead and ends short, map_cluster is forgotten.
+            if new_cluster.domain.start < map_cluster.domain.start
+                && new_cluster.domain.end < map_cluster.domain.end
+            {
+                /*
+                new_cluster overlaps the start of map_cluster,
+                but ends short of map_cluster end.
+
+                ACTION: Crop map_cluster to start at end of new_cluster.
+                */
+
+                map_cluster.domain.start = new_cluster.domain.end;
+                new_map.push(map_cluster);
+            } else if new_cluster.domain.end < map_cluster.domain.end {
+                /*
+                new_cluster starts within map_cluster domain.
+
+                ACTION: Crop
+                */
+
+                let domain_end = map_cluster.domain.end;
+
+                // Crop current object.
+                map_cluster.domain.end = new_cluster.domain.start;
+                new_map.push(map_cluster);
+
+                if new_cluster.domain.end < map_cluster.domain.end {
+                    /*
+                    new_cluster is within map_cluster.
+
+                    ACTION: Crop & Fracture map_cluster
+                    NOTE: Crop completed above.
+                    */
+
+                    new_map.push(Cluster {
+                        domain: Domain {
+                            start: new_cluster.domain.end,
+                            end: domain_end,
+                        },
+                        stage: map_cluster.stage.to_owned(),
+                    });
+                }
+            } else {
+                /*
+                No overlap.
+
+                ACTION: Transfer
+                */
+
+                new_map.push(map_cluster);
+            }
+        }
+
+        self.map = new_map;
+        self
+    }
+
+    /// Get current recovery stage.
+    pub fn get_stage(&self) -> Stage {
+        let mut recover_stage = Stage::Damaged;
+
+        for cluster in self.map.iter() {
+            match cluster.stage {
+                Stage::Untested => return Stage::Untested,
+                Stage::ForIsolation(_) => {
+                    if recover_stage == Stage::Damaged || cluster.stage < recover_stage {
+                        // Note that recover_stage after first condition is
+                        // only ever Stage::ForIsolation(_), thus PartialEq,
+                        // PartialOrd are useful for comparing the internal value.
+                        recover_stage = cluster.stage
+                    }
+                }
+                Stage::Damaged => (),
+                Stage::Intact => unreachable!(),
+            }
+        }
+
+        recover_stage
+    }
+
+    /// Get clusters of common stage.
+    pub fn get_clusters(&self, stage: Stage) -> Vec<Cluster> {
+        self.map
+            .iter()
+            .filter_map(|mc| {
+                if mc.stage == stage {
+                    Some(mc.to_owned())
+                } else {
+                    None
+                }
+            })
+            .collect()
+    }
+
+    /// Defragments cluster groups.
+    /// I.E. check forwards every cluster from current until stage changes,
+    /// then group at once.
+    pub fn defrag(&mut self) -> &mut Self {
+        let mut new_map: Vec<Cluster> = vec![];
+
+        // Fetch first cluster.
+        let mut start_cluster = self.map.iter().find(|c| c.domain.start == 0).unwrap();
+
+        // Even though this would be initialized by its first read,
+        // the compiler won't stop whining, and idk how to assert that to it.
+        let mut end_cluster = Cluster::default();
+        let mut new_cluster: Cluster;
+
+        let mut stage_common: bool;
+        let mut is_finished = false;
+
+        while !is_finished {
+            stage_common = true;
+
+            // Start a new cluster based on the cluster following
+            // the end of last new_cluster.
+            new_cluster = start_cluster.to_owned();
+
+            // While stage is common, and not finished,
+            // find each trailing cluster.
+            while stage_common && !is_finished {
+                end_cluster = start_cluster.to_owned();
+
+                if end_cluster.domain.end != self.domain.end {
+                    start_cluster = self
+                        .map
+                        .iter()
+                        .find(|c| end_cluster.domain.end == c.domain.start)
+                        .unwrap();
+
+                    stage_common = new_cluster.stage == start_cluster.stage
+                } else {
+                    is_finished = true;
+                }
+            }
+
+            // Set the new ending, encapsulating any clusters of common stage.
+            new_cluster.domain.end = end_cluster.domain.end;
+            new_map.push(new_cluster);
+        }
+
+        self.map = new_map;
+        self
+    }
+}
+
+pub fn write_map_to_file(file: File, map: &MapFile) -> ron::error::Result<String> {
+    ron::ser::to_string_pretty(
+        map,
+        ron::ser::PrettyConfig::new()
+            .new_line("\n".to_string())
+            .struct_names(true),
+    )
+}