//! Copyright (c) 2022-2026 GitDataAi All rights reserved.

use crate::bare::GitBare;
use crate::error::GitResult;
use crate::pb::*;

impl GitBare {
    /// Update multiple refs atomically using `git update-ref --stdin`.
    pub fn update_references(
        &self,
        request: UpdateReferencesRequest,
    ) -> GitResult<UpdateReferencesResponse> {
        let mut stdin_input = String::new();
        for update in &request.updates {
            crate::sanitize::validate_ref_name(&update.ref_name)?;
            crate::sanitize::validate_revision(&update.new_oid)?;
            if !update.old_oid.is_empty() {
                crate::sanitize::validate_revision(&update.old_oid)?;
                stdin_input.push_str(&format!(
                    "update {} {} {}\n",
                    update.ref_name, update.new_oid, update.old_oid
                ));
            } else {
                stdin_input.push_str(&format!("update {} {}\n", update.ref_name, update.new_oid));
            }
        }
        if stdin_input.is_empty() {
            return Ok(UpdateReferencesResponse::default());
        }

        let mut child = std::process::Command::new("git")
            .args([
                "--git-dir",
                &self.bare_dir.to_string_lossy(),
                "update-ref",
                "--stdin",
            ])
            .stdin(std::process::Stdio::piped())
            .stdout(std::process::Stdio::piped())
            .stderr(std::process::Stdio::piped())
            .spawn()
            .map_err(|e| crate::error::GitError::CommandFailed {
                status_code: None,
                stderr: e.to_string(),
            })?;

        if let Some(ref mut stdin) = child.stdin {
            use std::io::Write;
            stdin.write_all(stdin_input.as_bytes()).map_err(|e| {
                crate::error::GitError::CommandFailed {
                    status_code: None,
                    stderr: format!("failed to write stdin: {e}"),
                }
            })?;
        }
        drop(child.stdin.take());
        let output =
            child
                .wait_with_output()
                .map_err(|e| crate::error::GitError::CommandFailed {
                    status_code: None,
                    stderr: e.to_string(),
                })?;

        let stderr = String::from_utf8_lossy(&output.stderr).into_owned();
        if !output.status.success() {
            return Ok(UpdateReferencesResponse {
                failed_refs: request.updates.iter().map(|u| u.ref_name.clone()).collect(),
                error: stderr.trim().to_string(),
            });
        }
        Ok(UpdateReferencesResponse::default())
    }

    /// Delete refs in bulk.
    pub fn delete_refs(&self, request: DeleteRefsRequest) -> GitResult<DeleteRefsResponse> {
        let mut failed = Vec::new();
        let mut error_msg = String::new();

        for ref_name in &request.ref_names {
            crate::sanitize::validate_ref_name(ref_name)?;
            let output = std::process::Command::new("git")
                .args([
                    "--git-dir",
                    &self.bare_dir.to_string_lossy(),
                    "update-ref",
                    "-d",
                    ref_name,
                ])
                .stdout(std::process::Stdio::piped())
                .stderr(std::process::Stdio::piped())
                .output()
                .map_err(|e| crate::error::GitError::CommandFailed {
                    status_code: None,
                    stderr: e.to_string(),
                })?;

            if !output.status.success() {
                failed.push(ref_name.clone());
                if error_msg.is_empty() {
                    error_msg = String::from_utf8_lossy(&output.stderr).trim().to_string();
                }
            }
        }

        Ok(DeleteRefsResponse {
            failed_refs: failed,
            error: error_msg,
        })
    }

    /// Write a single ref with optional expected-old-oid check.
    pub fn write_ref(&self, request: WriteRefRequest) -> GitResult<WriteRefResponse> {
        crate::sanitize::validate_ref_name(&request.ref_name)?;
        crate::sanitize::validate_revision(&request.new_oid)?;

        let mut args = vec![
            "--git-dir".to_string(),
            self.bare_dir.to_string_lossy().into_owned(),
            "update-ref".to_string(),
            request.ref_name.clone(),
            request.new_oid.clone(),
        ];

        if !request.old_oid.is_empty() {
            crate::sanitize::validate_revision(&request.old_oid)?;
            args.push(request.old_oid.clone());
        }

        let output = std::process::Command::new("git")
            .args(&args)
            .stdout(std::process::Stdio::piped())
            .stderr(std::process::Stdio::piped())
            .output()
            .map_err(|e| crate::error::GitError::CommandFailed {
                status_code: None,
                stderr: e.to_string(),
            })?;

        if !output.status.success() {
            return Ok(WriteRefResponse {
                ok: false,
                error: String::from_utf8_lossy(&output.stderr).trim().to_string(),
            });
        }

        Ok(WriteRefResponse {
            ok: true,
            error: String::new(),
        })
    }

    /// Check if a ref exists.
    pub fn ref_exists(&self, request: RefExistsRequest) -> GitResult<RefExistsResponse> {
        crate::sanitize::validate_ref_name(&request.ref_name)?;
        let repo = self.gix_repo()?;
        let exists = repo
            .try_find_reference(&request.ref_name)
            .ok()
            .flatten()
            .is_some();
        Ok(RefExistsResponse { exists })
    }

    /// Find the default branch name.
    pub fn find_default_branch_name(&self) -> GitResult<FindDefaultBranchNameResponse> {
        let result = std::process::Command::new("git")
            .args([
                "--git-dir",
                &self.bare_dir.to_string_lossy(),
                "symbolic-ref",
                "HEAD",
            ])
            .output()
            .map_err(|e| crate::error::GitError::CommandFailed {
                status_code: None,
                stderr: e.to_string(),
            })?;
        if !result.status.success() {
            return Err(crate::error::GitError::CommandFailed {
                status_code: result.status.code(),
                stderr: String::from_utf8_lossy(&result.stderr).trim().to_string(),
            });
        }
        let name = String::from_utf8_lossy(&result.stdout)
            .trim()
            .strip_prefix("refs/heads/")
            .map(|b| b.to_string())
            .unwrap_or_default();
        Ok(FindDefaultBranchNameResponse { name })
    }
}