1 files changed, 159 insertions, 10 deletions

diff --git a/src/chunker/context.rs b/src/chunker/context.rs
index d918937..45283bc 100644
--- a/src/chunker/context.rs
+++ b/src/chunker/context.rs
@@ -5,46 +5,195 @@ use log::{error, warn};
 use crate::{
     chunker::{constants::BUTCK_METADATA_DIR_NAME, rw::storage::hash::ChunkWriteHash},
     special_argument, special_flag,
+    storage::{ButckRWError, build, write},
     utils::file_input_solve::parse_path_input,
 };
 
+pub struct Butck;
+impl Butck {
+    pub fn write(files: Vec<PathBuf>, storage: PathBuf) -> ButckContext {
+        ButckContext::default()
+            .with_file_paths(files)
+            .with_storage_path(storage)
+            .with_write_mode()
+    }
+
+    pub fn build(index_files: Vec<PathBuf>, storage: PathBuf) -> ButckContext {
+        ButckContext::default()
+            .with_file_paths(index_files)
+            .with_storage_path(storage)
+            .with_build_mode()
+    }
+}
+
+#[derive(Debug, Default)]
+enum ButckMethod {
+    #[default]
+    None,
+    Write,
+    Build,
+}
+
 #[derive(Debug, Default)]
 pub struct ButckContext {
+    method: ButckMethod,
+
     /// All input files
+    /// They will be processed by build / write operations
+    /// For build operation, it expects *.bidx file collections
+    /// For write operation, it expects file path collections without directories
     pub file_paths: Vec<PathBuf>,
 
-    /// Path of Butck Storage
+    /// Storage repository path
+    /// It specifies the storage location for file chunks
+    /// For build operation, chunks will be read from this directory
+    /// For write operation, chunks will be output to this directory
+    ///
+    /// If set to None, the program cannot execute successfully
     pub storage_path: Option<PathBuf>,
 
-    // Display chunk boundaries
+    /// Display chunk boundaries
+    ///
+    /// If set to true, no chunking or building logic will be executed
+    /// Only boundary information will be output to stdio
     pub display_boundaries: bool,
 
-    /// Whether to read in stream mode
+    /// Stream reading
+    /// If set to Some(size)
+    /// Will load data of size each time and process it with streaming strategy
     pub stream_read: Option<u32>,
 
-    /// Whether to read files using memory mapping
+    /// Memory map reading
+    ///
+    /// If enabled, will use Memmap to map files to memory for access
     pub memmap_read: bool,
 
-    /// Register name
+    /// Registration name
+    /// When set to Some(name)
+    /// After write operation completes,
+    /// the corresponding bidx file will be registered to the storage directory's registry
+    ///
+    /// In build phase, registration name can be used directly to create files
     pub register_name: Option<String>,
 
-    /// Chunking policy name
+    /// Chunking policy
+    /// For command line program, can use `butck lspolicy-all` to query
+    /// It specifies the concrete chunking policy,
+    /// reasonable policy settings can significantly improve file deduplication rate
+    ///
+    /// If set to None, the program cannot execute successfully
     pub policy_name: Option<String>,
 
-    /// Hash algorithm used for chunking
+    /// Chunk hash
+    /// Stores hash representation of chunks
+    /// Currently supports Blake3 and SHA256
     pub chunk_hash: ChunkWriteHash,
 
-    /// Output directory
+    /// Output path
+    /// For build operation, built files will be output here
+    /// For write operation, generated *.bidx files will be output here
+    ///
+    /// Defaults to current runtime directory
     pub output_dir: PathBuf,
 
-    /// Output file (not available for some commands)
+    /// Output file
+    /// Precisely specifies output file name
+    ///
+    /// If number of input files is greater than 1, program cannot execute successfully
     pub output_file: Option<PathBuf>,
 
-    /// Override parameters
+    /// Parameters
+    /// Provides concrete parameters for the policy
     pub params: HashMap<String, String>,
 }
 
 impl ButckContext {
+    pub fn with_build_mode(mut self) -> Self {
+        self.method = ButckMethod::Build;
+        self
+    }
+
+    pub fn with_write_mode(mut self) -> Self {
+        self.method = ButckMethod::Write;
+        self
+    }
+
+    pub fn with_storage_path(mut self, path: PathBuf) -> Self {
+        self.storage_path = Some(path);
+        self
+    }
+
+    pub fn with_display_boundaries(mut self, display: bool) -> Self {
+        self.display_boundaries = display;
+        self
+    }
+
+    pub fn with_stream_read(mut self, size: Option<u32>) -> Self {
+        self.stream_read = size;
+        self
+    }
+
+    pub fn with_memmap_read(mut self, use_memmap: bool) -> Self {
+        self.memmap_read = use_memmap;
+        self
+    }
+
+    pub fn with_register_name(mut self, name: Option<String>) -> Self {
+        self.register_name = name;
+        self
+    }
+
+    pub fn with_policy_name(mut self, name: Option<String>) -> Self {
+        self.policy_name = name;
+        self
+    }
+
+    pub fn with_chunk_hash(mut self, hash: ChunkWriteHash) -> Self {
+        self.chunk_hash = hash;
+        self
+    }
+
+    pub fn with_output_dir(mut self, dir: PathBuf) -> Self {
+        self.output_dir = dir;
+        self
+    }
+
+    pub fn with_output_file(mut self, file: Option<PathBuf>) -> Self {
+        self.output_file = file;
+        self
+    }
+
+    pub fn param(mut self, key: String, value: String) -> Self {
+        self.params.insert(key, value);
+        self
+    }
+
+    pub fn with_file_paths(mut self, paths: Vec<PathBuf>) -> Self {
+        self.file_paths = paths;
+        self
+    }
+
+    pub fn add_file(mut self, path: PathBuf) -> Self {
+        self.file_paths.push(path);
+        self
+    }
+
+    pub async fn exec(self) -> Result<(), ButckRWError> {
+        match self.method {
+            ButckMethod::None => Ok(()),
+            ButckMethod::Write => {
+                write(self).await?;
+                Ok(())
+            }
+            ButckMethod::Build => {
+                build(self).await?;
+                Ok(())
+            }
+        }
+    }
+}
+
+impl ButckContext {
     /// Apply the args of ChunkerContext to itself
     pub fn from_args(mut args: Vec<String>) -> Self {
         let mut ctx = ButckContext::default();