cascade_cli/stack/
rebase.rs

1use crate::errors::{CascadeError, Result};
2use crate::git::{ConflictAnalyzer, GitRepository};
3use crate::stack::{Stack, StackManager};
4use chrono::Utc;
5use serde::{Deserialize, Serialize};
6use std::collections::HashMap;
7use tracing::{debug, info, warn};
8use uuid::Uuid;
9
10/// Conflict resolution result
11#[derive(Debug, Clone)]
12enum ConflictResolution {
13    /// Conflict was successfully resolved
14    Resolved,
15    /// Conflict is too complex for automatic resolution
16    TooComplex,
17}
18
19/// Represents a conflict region in a file
20#[derive(Debug, Clone)]
21#[allow(dead_code)]
22struct ConflictRegion {
23    /// Byte position where conflict starts
24    start: usize,
25    /// Byte position where conflict ends  
26    end: usize,
27    /// Line number where conflict starts
28    start_line: usize,
29    /// Line number where conflict ends
30    end_line: usize,
31    /// Content from "our" side (before separator)
32    our_content: String,
33    /// Content from "their" side (after separator)
34    their_content: String,
35}
36
37/// Strategy for rebasing stacks (force-push is the only valid approach for preserving PR history)
38#[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
39pub enum RebaseStrategy {
40    /// Force-push rebased commits to original branches (preserves PR history)
41    /// This is the industry standard used by Graphite, Phabricator, spr, etc.
42    ForcePush,
43    /// Interactive rebase with conflict resolution
44    Interactive,
45}
46
47/// Options for rebase operations
48#[derive(Debug, Clone)]
49pub struct RebaseOptions {
50    /// The rebase strategy to use
51    pub strategy: RebaseStrategy,
52    /// Whether to run interactively (prompt for user input)
53    pub interactive: bool,
54    /// Target base branch to rebase onto
55    pub target_base: Option<String>,
56    /// Whether to preserve merge commits
57    pub preserve_merges: bool,
58    /// Whether to auto-resolve simple conflicts
59    pub auto_resolve: bool,
60    /// Maximum number of retries for conflict resolution
61    pub max_retries: usize,
62    /// Skip pulling latest changes (when already done by caller)
63    pub skip_pull: Option<bool>,
64    /// Original working branch to restore after rebase (if different from base)
65    /// This is critical to prevent updating the base branch when sync checks out to it
66    pub original_working_branch: Option<String>,
67}
68
69/// Result of a rebase operation
70#[derive(Debug)]
71pub struct RebaseResult {
72    /// Whether the rebase was successful
73    pub success: bool,
74    /// Old branch to new branch mapping
75    pub branch_mapping: HashMap<String, String>,
76    /// Commits that had conflicts
77    pub conflicts: Vec<String>,
78    /// New commit hashes
79    pub new_commits: Vec<String>,
80    /// Error message if rebase failed
81    pub error: Option<String>,
82    /// Summary of changes made
83    pub summary: String,
84}
85
86/// RAII guard to ensure temporary branches are cleaned up even on error/panic
87///
88/// This stores branch names and provides a cleanup method that can be called
89/// with a GitRepository reference. The Drop trait ensures cleanup happens
90/// even if the rebase function panics or returns early with an error.
91#[allow(dead_code)]
92struct TempBranchCleanupGuard {
93    branches: Vec<String>,
94    cleaned: bool,
95}
96
97#[allow(dead_code)]
98impl TempBranchCleanupGuard {
99    fn new() -> Self {
100        Self {
101            branches: Vec::new(),
102            cleaned: false,
103        }
104    }
105
106    fn add_branch(&mut self, branch: String) {
107        self.branches.push(branch);
108    }
109
110    /// Perform cleanup with provided git repository
111    fn cleanup(&mut self, git_repo: &GitRepository) {
112        if self.cleaned || self.branches.is_empty() {
113            return;
114        }
115
116        info!("๐Ÿงน Cleaning up {} temporary branches", self.branches.len());
117        for branch in &self.branches {
118            if let Err(e) = git_repo.delete_branch_unsafe(branch) {
119                warn!("Failed to delete temp branch {}: {}", branch, e);
120                // Continue with cleanup even if one fails
121            }
122        }
123        self.cleaned = true;
124    }
125}
126
127impl Drop for TempBranchCleanupGuard {
128    fn drop(&mut self) {
129        if !self.cleaned && !self.branches.is_empty() {
130            // This path is only hit on panic or unexpected early return
131            // We can't access git_repo here, so just log the branches that need manual cleanup
132            warn!(
133                "โš ๏ธ  {} temporary branches were not cleaned up: {}",
134                self.branches.len(),
135                self.branches.join(", ")
136            );
137            warn!("Run 'ca cleanup' to remove orphaned temporary branches");
138        }
139    }
140}
141
142/// Manages rebase operations for stacks
143pub struct RebaseManager {
144    stack_manager: StackManager,
145    git_repo: GitRepository,
146    options: RebaseOptions,
147    conflict_analyzer: ConflictAnalyzer,
148}
149
150impl Default for RebaseOptions {
151    fn default() -> Self {
152        Self {
153            strategy: RebaseStrategy::ForcePush,
154            interactive: false,
155            target_base: None,
156            preserve_merges: true,
157            auto_resolve: true,
158            max_retries: 3,
159            skip_pull: None,
160            original_working_branch: None,
161        }
162    }
163}
164
165impl RebaseManager {
166    /// Create a new rebase manager
167    pub fn new(
168        stack_manager: StackManager,
169        git_repo: GitRepository,
170        options: RebaseOptions,
171    ) -> Self {
172        Self {
173            stack_manager,
174            git_repo,
175            options,
176            conflict_analyzer: ConflictAnalyzer::new(),
177        }
178    }
179
180    /// Consume the rebase manager and return the updated stack manager
181    pub fn into_stack_manager(self) -> StackManager {
182        self.stack_manager
183    }
184
185    /// Rebase an entire stack onto a new base
186    pub fn rebase_stack(&mut self, stack_id: &Uuid) -> Result<RebaseResult> {
187        debug!("Starting rebase for stack {}", stack_id);
188
189        let stack = self
190            .stack_manager
191            .get_stack(stack_id)
192            .ok_or_else(|| CascadeError::config(format!("Stack {stack_id} not found")))?
193            .clone();
194
195        match self.options.strategy {
196            RebaseStrategy::ForcePush => self.rebase_with_force_push(&stack),
197            RebaseStrategy::Interactive => self.rebase_interactive(&stack),
198        }
199    }
200
201    /// Rebase using force-push strategy (industry standard for stacked diffs)
202    /// This updates local branches in-place, then force-pushes ONLY branches with existing PRs
203    /// to preserve PR history - the approach used by Graphite, Phabricator, spr, etc.
204    fn rebase_with_force_push(&mut self, stack: &Stack) -> Result<RebaseResult> {
205        use crate::cli::output::Output;
206
207        // Check if there's an in-progress cherry-pick from a previous failed sync
208        if self.has_in_progress_cherry_pick()? {
209            return self.handle_in_progress_cherry_pick(stack);
210        }
211
212        Output::section(format!("Rebasing stack: {}", stack.name));
213
214        let mut result = RebaseResult {
215            success: true,
216            branch_mapping: HashMap::new(),
217            conflicts: Vec::new(),
218            new_commits: Vec::new(),
219            error: None,
220            summary: String::new(),
221        };
222
223        let target_base = self
224            .options
225            .target_base
226            .as_ref()
227            .unwrap_or(&stack.base_branch)
228            .clone(); // Clone to avoid borrow issues
229
230        // Use the original working branch passed in options, or detect current branch
231        // CRITICAL: sync_stack passes the original branch before it checks out to base
232        // This prevents us from thinking we started on the base branch
233        let original_branch = self
234            .options
235            .original_working_branch
236            .clone()
237            .or_else(|| self.git_repo.get_current_branch().ok());
238
239        // SAFETY: Warn if we're starting on the base branch (unusual but valid)
240        // This can happen if user manually runs rebase while on base branch
241        if let Some(ref orig) = original_branch {
242            if orig == &target_base {
243                debug!(
244                    "Original working branch is base branch '{}' - will skip working branch update",
245                    orig
246                );
247            }
248        }
249
250        // Note: Caller (sync_stack) has already checked out base branch when skip_pull=true
251        // Only pull if not already done by caller (like sync command)
252        if !self.options.skip_pull.unwrap_or(false) {
253            if let Err(e) = self.pull_latest_changes(&target_base) {
254                Output::warning(format!("Could not pull latest changes: {}", e));
255            }
256        }
257
258        // Reset working directory to clean state before rebase
259        if let Err(e) = self.git_repo.reset_to_head() {
260            Output::warning(format!("Could not reset working directory: {}", e));
261        }
262
263        let mut current_base = target_base.clone();
264        let entry_count = stack.entries.len();
265        let mut temp_branches: Vec<String> = Vec::new(); // Track temp branches for cleanup
266        let mut branches_to_push: Vec<(String, String)> = Vec::new(); // (branch_name, pr_number)
267
268        // Handle empty stack early
269        if entry_count == 0 {
270            println!(); // Spacing
271            Output::info("Stack has no entries yet");
272            Output::tip("Use 'ca push' to add commits to this stack");
273
274            result.summary = "Stack is empty".to_string();
275
276            // Print success with summary (consistent with non-empty path)
277            println!(); // Spacing
278            Output::success(&result.summary);
279
280            // Save metadata and return
281            self.stack_manager.save_to_disk()?;
282            return Ok(result);
283        }
284
285        println!(); // Spacing before tree
286        let plural = if entry_count == 1 { "entry" } else { "entries" };
287        println!("Rebasing {} {}...", entry_count, plural);
288
289        // Phase 1: Rebase all entries locally (libgit2 only - no CLI commands)
290        for (index, entry) in stack.entries.iter().enumerate() {
291            let original_branch = &entry.branch;
292
293            // Check if this entry is already correctly based on the current base
294            // If so, skip rebasing it (avoids creating duplicate commits)
295            if self
296                .git_repo
297                .is_commit_based_on(&entry.commit_hash, &current_base)
298                .unwrap_or(false)
299            {
300                tracing::debug!(
301                    "Entry '{}' is already correctly based on '{}', skipping rebase",
302                    original_branch,
303                    current_base
304                );
305
306                // Track which branches need to be pushed (only those with PRs)
307                let tree_char = if index + 1 == entry_count {
308                    "โ””โ”€"
309                } else {
310                    "โ”œโ”€"
311                };
312
313                if let Some(pr_num) = &entry.pull_request_id {
314                    println!("   {} {} (PR #{})", tree_char, original_branch, pr_num);
315                    branches_to_push.push((original_branch.clone(), pr_num.clone()));
316                } else {
317                    println!("   {} {} (not submitted)", tree_char, original_branch);
318                }
319
320                result
321                    .branch_mapping
322                    .insert(original_branch.clone(), original_branch.clone());
323
324                // This branch becomes the base for the next entry
325                current_base = original_branch.clone();
326                continue;
327            }
328
329            // Create a temporary branch from the current base
330            // This avoids committing directly to protected branches like develop/main
331            let temp_branch = format!("{}-temp-{}", original_branch, Utc::now().timestamp());
332            temp_branches.push(temp_branch.clone()); // Track for cleanup
333            self.git_repo
334                .create_branch(&temp_branch, Some(&current_base))?;
335            self.git_repo.checkout_branch_silent(&temp_branch)?;
336
337            // Cherry-pick the commit onto the temp branch (NOT the protected base!)
338            match self.cherry_pick_commit(&entry.commit_hash) {
339                Ok(new_commit_hash) => {
340                    result.new_commits.push(new_commit_hash.clone());
341
342                    // Get the commit that's now at HEAD (the cherry-picked commit)
343                    let rebased_commit_id = self.git_repo.get_head_commit()?.id().to_string();
344
345                    // Update the original branch to point to this rebased commit
346                    // This is LOCAL ONLY - moves refs/heads/<branch> to the commit on temp branch
347                    self.git_repo
348                        .update_branch_to_commit(original_branch, &rebased_commit_id)?;
349
350                    // Track which branches need to be pushed (only those with PRs)
351                    let tree_char = if index + 1 == entry_count {
352                        "โ””โ”€"
353                    } else {
354                        "โ”œโ”€"
355                    };
356
357                    if let Some(pr_num) = &entry.pull_request_id {
358                        println!("   {} {} (PR #{})", tree_char, original_branch, pr_num);
359                        branches_to_push.push((original_branch.clone(), pr_num.clone()));
360                    } else {
361                        println!("   {} {} (not submitted)", tree_char, original_branch);
362                    }
363
364                    result
365                        .branch_mapping
366                        .insert(original_branch.clone(), original_branch.clone());
367
368                    // Update stack entry with new commit hash
369                    self.update_stack_entry(
370                        stack.id,
371                        &entry.id,
372                        original_branch,
373                        &rebased_commit_id,
374                    )?;
375
376                    // This branch becomes the base for the next entry
377                    current_base = original_branch.clone();
378                }
379                Err(e) => {
380                    result.conflicts.push(entry.commit_hash.clone());
381
382                    if !self.options.auto_resolve {
383                        println!(); // Spacing before error
384                        Output::error(e.to_string());
385                        result.success = false;
386                        result.error = Some(format!(
387                            "Conflict in {}: {}\n\n\
388                            MANUAL CONFLICT RESOLUTION REQUIRED\n\
389                            =====================================\n\n\
390                            Step 1: Analyze conflicts\n\
391                            โ†’ Run: ca conflicts\n\
392                            โ†’ This shows which conflicts are in which files\n\n\
393                            Step 2: Resolve conflicts in your editor\n\
394                            โ†’ Open conflicted files and edit them\n\
395                            โ†’ Remove conflict markers (<<<<<<, ======, >>>>>>)\n\
396                            โ†’ Keep the code you want\n\
397                            โ†’ Save the files\n\n\
398                            Step 3: Mark conflicts as resolved\n\
399                            โ†’ Run: git add <resolved-files>\n\
400                            โ†’ Or: git add -A (to stage all resolved files)\n\n\
401                            Step 4: Complete the sync\n\
402                            โ†’ Run: ca sync\n\
403                            โ†’ Cascade will detect resolved conflicts and continue\n\n\
404                            Alternative: Abort and start over\n\
405                            โ†’ Run: git cherry-pick --abort\n\
406                            โ†’ Then: ca sync (starts fresh)\n\n\
407                            TIP: Enable auto-resolution for simple conflicts:\n\
408                            โ†’ Run: ca sync --auto-resolve\n\
409                            โ†’ Only complex conflicts will require manual resolution",
410                            entry.commit_hash, e
411                        ));
412                        break;
413                    }
414
415                    // Try to resolve automatically
416                    match self.auto_resolve_conflicts(&entry.commit_hash) {
417                        Ok(fully_resolved) => {
418                            if !fully_resolved {
419                                result.success = false;
420                                result.error = Some(format!(
421                                    "Conflicts in commit {}\n\n\
422                                    To resolve:\n\
423                                    1. Fix conflicts in your editor\n\
424                                    2. Run: ca sync --continue\n\n\
425                                    Or abort:\n\
426                                    โ†’ Run: git cherry-pick --abort",
427                                    &entry.commit_hash[..8]
428                                ));
429                                break;
430                            }
431
432                            // Commit the resolved changes
433                            let commit_message =
434                                format!("Auto-resolved conflicts in {}", &entry.commit_hash[..8]);
435
436                            // CRITICAL: Check if there are actually changes to commit
437                            debug!("Checking staged files before commit");
438                            let staged_files = self.git_repo.get_staged_files()?;
439
440                            if staged_files.is_empty() {
441                                // NO FILES STAGED! This means auto-resolve didn't actually stage anything
442                                // This is the bug - cherry-pick failed, but has_conflicts() returned false
443                                // so auto-resolve exited early without staging anything
444                                result.success = false;
445                                result.error = Some(format!(
446                                    "CRITICAL BUG DETECTED: Cherry-pick failed but no files were staged!\n\n\
447                                    This indicates a Git state issue after cherry-pick failure.\n\n\
448                                    RECOVERY STEPS:\n\
449                                    ================\n\n\
450                                    Step 1: Check Git status\n\
451                                    โ†’ Run: git status\n\
452                                    โ†’ Check if there are any changes in working directory\n\n\
453                                    Step 2: Check for conflicts manually\n\
454                                    โ†’ Run: git diff\n\
455                                    โ†’ Look for conflict markers (<<<<<<, ======, >>>>>>)\n\n\
456                                    Step 3: Abort the cherry-pick\n\
457                                    โ†’ Run: git cherry-pick --abort\n\n\
458                                    Step 4: Report this bug\n\
459                                    โ†’ This is a known issue we're investigating\n\
460                                    โ†’ Cherry-pick failed for commit {}\n\
461                                    โ†’ But Git reported no conflicts and no staged files\n\n\
462                                    Step 5: Try manual resolution\n\
463                                    โ†’ Run: ca sync --no-auto-resolve\n\
464                                    โ†’ Manually resolve conflicts as they appear",
465                                    &entry.commit_hash[..8]
466                                ));
467                                warn!("CRITICAL - No files staged after auto-resolve!");
468                                break;
469                            }
470
471                            debug!("{} files staged", staged_files.len());
472
473                            match self.git_repo.commit(&commit_message) {
474                                Ok(new_commit_id) => {
475                                    debug!(
476                                        "Created commit {} with message '{}'",
477                                        &new_commit_id[..8],
478                                        commit_message
479                                    );
480
481                                    Output::success("Auto-resolved conflicts");
482                                    result.new_commits.push(new_commit_id.clone());
483                                    let rebased_commit_id = new_commit_id;
484
485                                    // Update the original branch to point to this rebased commit
486                                    self.git_repo.update_branch_to_commit(
487                                        original_branch,
488                                        &rebased_commit_id,
489                                    )?;
490
491                                    // Track which branches need to be pushed (only those with PRs)
492                                    let tree_char = if index + 1 == entry_count {
493                                        "โ””โ”€"
494                                    } else {
495                                        "โ”œโ”€"
496                                    };
497
498                                    if let Some(pr_num) = &entry.pull_request_id {
499                                        println!(
500                                            "   {} {} (PR #{})",
501                                            tree_char, original_branch, pr_num
502                                        );
503                                        branches_to_push
504                                            .push((original_branch.clone(), pr_num.clone()));
505                                    } else {
506                                        println!(
507                                            "   {} {} (not submitted)",
508                                            tree_char, original_branch
509                                        );
510                                    }
511
512                                    result
513                                        .branch_mapping
514                                        .insert(original_branch.clone(), original_branch.clone());
515
516                                    // Update stack entry with new commit hash
517                                    self.update_stack_entry(
518                                        stack.id,
519                                        &entry.id,
520                                        original_branch,
521                                        &rebased_commit_id,
522                                    )?;
523
524                                    // This branch becomes the base for the next entry
525                                    current_base = original_branch.clone();
526                                }
527                                Err(commit_err) => {
528                                    result.success = false;
529                                    result.error = Some(format!(
530                                        "Could not commit auto-resolved conflicts: {}\n\n\
531                                        This usually means:\n\
532                                        - Git index is locked (another process accessing repo)\n\
533                                        - File permissions issue\n\
534                                        - Disk space issue\n\n\
535                                        Recovery:\n\
536                                        1. Check if another Git operation is running\n\
537                                        2. Run 'rm -f .git/index.lock' if stale lock exists\n\
538                                        3. Run 'git status' to check repo state\n\
539                                        4. Retry 'ca sync' after fixing the issue",
540                                        commit_err
541                                    ));
542                                    break;
543                                }
544                            }
545                        }
546                        Err(resolve_err) => {
547                            result.success = false;
548                            result.error = Some(format!(
549                                "Could not resolve conflicts: {}\n\n\
550                                Recovery:\n\
551                                1. Check repo state: 'git status'\n\
552                                2. If files are staged, commit or reset them: 'git reset --hard HEAD'\n\
553                                3. Remove any lock files: 'rm -f .git/index.lock'\n\
554                                4. Retry 'ca sync'",
555                                resolve_err
556                            ));
557                            break;
558                        }
559                    }
560                }
561            }
562        }
563
564        // Cleanup temp branches before returning to original branch
565        // Must checkout away from temp branches first
566        if !temp_branches.is_empty() {
567            // Force checkout to base branch to allow temp branch deletion
568            // Use unsafe checkout to bypass safety checks since we know this is cleanup
569            if let Err(e) = self.git_repo.checkout_branch_unsafe(&target_base) {
570                debug!("Could not checkout base for cleanup: {}", e);
571                // If we can't checkout, we can't delete temp branches
572                // This is non-critical - temp branches will be cleaned up eventually
573            } else {
574                // Successfully checked out - now delete temp branches
575                for temp_branch in &temp_branches {
576                    if let Err(e) = self.git_repo.delete_branch_unsafe(temp_branch) {
577                        debug!("Could not delete temp branch {}: {}", temp_branch, e);
578                    }
579                }
580            }
581        }
582
583        // Phase 2: Push all branches with PRs to remote (git CLI - after all libgit2 operations)
584        // This batch approach prevents index lock conflicts between libgit2 and git CLI
585        let pushed_count = branches_to_push.len();
586        let skipped_count = entry_count - pushed_count;
587
588        if !branches_to_push.is_empty() {
589            // Push branches silently - user will see the summary
590
591            for (branch_name, _pr_num) in &branches_to_push {
592                match self.git_repo.force_push_single_branch_auto(branch_name) {
593                    Ok(_) => {
594                        debug!("Pushed {} successfully", branch_name);
595                    }
596                    Err(e) => {
597                        Output::warning(format!("Could not push '{}': {}", branch_name, e));
598                        // Continue pushing other branches even if one fails
599                    }
600                }
601            }
602        }
603
604        // Update working branch to point to the top of the rebased stack
605        // This ensures subsequent `ca push` doesn't re-add old commits
606        if let Some(ref orig_branch) = original_branch {
607            // CRITICAL: Never update the base branch! Only update working branches
608            if orig_branch != &target_base {
609                // Get the last entry's branch (top of stack)
610                if let Some(last_entry) = stack.entries.last() {
611                    let top_branch = &last_entry.branch;
612
613                    // SAFETY CHECK: Detect if working branch has commits beyond the last stack entry
614                    // If it does, we need to preserve them - don't force-update the working branch
615                    if let (Ok(working_head), Ok(top_commit)) = (
616                        self.git_repo.get_branch_head(orig_branch),
617                        self.git_repo.get_branch_head(top_branch),
618                    ) {
619                        // Check if working branch is ahead of top stack entry
620                        if working_head != top_commit {
621                            // Get commits between top of stack and working branch head
622                            if let Ok(commits) = self.git_repo.get_commits_between(&top_commit, &working_head) {
623                                if !commits.is_empty() {
624                                    // Working branch has extra commits!
625                                    Output::error(format!(
626                                        "Cannot sync: Working branch '{}' has {} commit(s) not in the stack",
627                                        orig_branch,
628                                        commits.len()
629                                    ));
630                                    println!();
631                                    Output::sub_item("These commits would be lost if we proceed:");
632                                    for (i, commit) in commits.iter().take(5).enumerate() {
633                                        let message = commit.summary().unwrap_or("(no message)");
634                                        Output::sub_item(format!("  {}. {} - {}", i + 1, &commit.id().to_string()[..8], message));
635                                    }
636                                    if commits.len() > 5 {
637                                        Output::sub_item(format!("  ... and {} more", commits.len() - 5));
638                                    }
639                                    println!();
640                                    Output::tip("Add these commits to the stack first:");
641                                    Output::bullet(format!("Run: ca stack push"));
642                                    Output::bullet(format!("Then run: ca sync"));
643                                    println!();
644                                    
645                                    return Err(CascadeError::validation(
646                                        format!(
647                                            "Working branch '{}' has {} untracked commit(s). Add them to the stack with 'ca stack push' before syncing.",
648                                            orig_branch, commits.len()
649                                        )
650                                    ));
651                                }
652                            }
653                        }
654
655                        // Safe to update - working branch matches top of stack or is behind
656                        debug!(
657                            "Updating working branch '{}' to match top of stack ({})",
658                            orig_branch,
659                            &top_commit[..8]
660                        );
661
662                        if let Err(e) = self
663                            .git_repo
664                            .update_branch_to_commit(orig_branch, &top_commit)
665                        {
666                            Output::warning(format!(
667                                "Could not update working branch '{}' to top of stack: {}",
668                                orig_branch, e
669                            ));
670                        }
671                    }
672                }
673
674                // Return to original working branch
675                // Use unsafe checkout to force it (we're in cleanup phase, no uncommitted changes)
676                if let Err(e) = self.git_repo.checkout_branch_unsafe(orig_branch) {
677                    debug!(
678                        "Could not return to original branch '{}': {}",
679                        orig_branch, e
680                    );
681                    // Non-critical: User is left on base branch instead of working branch
682                }
683            } else {
684                // User was on base branch - this is unusual but valid
685                // Don't update base branch, just checkout back to it
686                debug!(
687                    "Skipping working branch update - user was on base branch '{}'",
688                    orig_branch
689                );
690                if let Err(e) = self.git_repo.checkout_branch_unsafe(orig_branch) {
691                    debug!("Could not return to base branch '{}': {}", orig_branch, e);
692                }
693            }
694        }
695
696        // Build summary message
697        result.summary = if pushed_count > 0 {
698            let pr_plural = if pushed_count == 1 { "" } else { "s" };
699            let entry_plural = if entry_count == 1 { "entry" } else { "entries" };
700
701            if skipped_count > 0 {
702                format!(
703                    "{} {} rebased ({} PR{} updated, {} not yet submitted)",
704                    entry_count, entry_plural, pushed_count, pr_plural, skipped_count
705                )
706            } else {
707                format!(
708                    "{} {} rebased ({} PR{} updated)",
709                    entry_count, entry_plural, pushed_count, pr_plural
710                )
711            }
712        } else {
713            let plural = if entry_count == 1 { "entry" } else { "entries" };
714            format!("{} {} rebased (no PRs to update yet)", entry_count, plural)
715        };
716
717        // Display result with proper formatting
718        println!(); // Spacing after tree
719        if result.success {
720            Output::success(&result.summary);
721        } else {
722            // Display error with proper icon
723            let error_msg = result
724                .error
725                .as_deref()
726                .unwrap_or("Rebase failed for unknown reason");
727            Output::error(error_msg);
728        }
729
730        // Save the updated stack metadata to disk
731        self.stack_manager.save_to_disk()?;
732
733        // CRITICAL: Return error if rebase failed
734        // Don't return Ok(result) with result.success = false - that's confusing!
735        if !result.success {
736            // Include the detailed error message (which contains conflict info)
737            let detailed_error = result.error.as_deref().unwrap_or("Rebase failed");
738            return Err(CascadeError::Branch(detailed_error.to_string()));
739        }
740
741        Ok(result)
742    }
743
744    /// Interactive rebase with user input
745    fn rebase_interactive(&mut self, stack: &Stack) -> Result<RebaseResult> {
746        info!("Starting interactive rebase for stack '{}'", stack.name);
747
748        let mut result = RebaseResult {
749            success: true,
750            branch_mapping: HashMap::new(),
751            conflicts: Vec::new(),
752            new_commits: Vec::new(),
753            error: None,
754            summary: String::new(),
755        };
756
757        println!("Interactive Rebase for Stack: {}", stack.name);
758        println!("   Base branch: {}", stack.base_branch);
759        println!("   Entries: {}", stack.entries.len());
760
761        if self.options.interactive {
762            println!("\nChoose action for each commit:");
763            println!("  (p)ick   - apply the commit");
764            println!("  (s)kip   - skip this commit");
765            println!("  (e)dit   - edit the commit message");
766            println!("  (q)uit   - abort the rebase");
767        }
768
769        // For now, automatically pick all commits
770        // In a real implementation, this would prompt the user
771        for entry in &stack.entries {
772            println!(
773                "  {} {} - {}",
774                entry.short_hash(),
775                entry.branch,
776                entry.short_message(50)
777            );
778
779            // Auto-pick for demo purposes
780            match self.cherry_pick_commit(&entry.commit_hash) {
781                Ok(new_commit) => result.new_commits.push(new_commit),
782                Err(_) => result.conflicts.push(entry.commit_hash.clone()),
783            }
784        }
785
786        result.summary = format!(
787            "Interactive rebase processed {} commits",
788            stack.entries.len()
789        );
790        Ok(result)
791    }
792
793    /// Cherry-pick a commit onto the current branch
794    fn cherry_pick_commit(&self, commit_hash: &str) -> Result<String> {
795        // Use the real cherry-pick implementation from GitRepository
796        let new_commit_hash = self.git_repo.cherry_pick(commit_hash)?;
797
798        // Check for any leftover staged changes after successful cherry-pick
799        if let Ok(staged_files) = self.git_repo.get_staged_files() {
800            if !staged_files.is_empty() {
801                // Commit any leftover staged changes silently
802                let cleanup_message = format!("Cleanup after cherry-pick {}", &commit_hash[..8]);
803                let _ = self.git_repo.commit_staged_changes(&cleanup_message);
804            }
805        }
806
807        Ok(new_commit_hash)
808    }
809
810    /// Attempt to automatically resolve conflicts
811    fn auto_resolve_conflicts(&self, commit_hash: &str) -> Result<bool> {
812        debug!("Starting auto-resolve for commit {}", commit_hash);
813
814        // Check if there are actually conflicts
815        let has_conflicts = self.git_repo.has_conflicts()?;
816        debug!("has_conflicts() = {}", has_conflicts);
817
818        // Check if cherry-pick is in progress
819        let cherry_pick_head = self.git_repo.path().join(".git").join("CHERRY_PICK_HEAD");
820        let cherry_pick_in_progress = cherry_pick_head.exists();
821
822        if !has_conflicts {
823            debug!("No conflicts detected by Git index");
824
825            // If cherry-pick is in progress but no conflicts detected, something is wrong
826            if cherry_pick_in_progress {
827                warn!("CHERRY_PICK_HEAD exists but no conflicts in index - aborting cherry-pick");
828
829                // Abort the cherry-pick to clean up
830                let _ = std::process::Command::new("git")
831                    .args(["cherry-pick", "--abort"])
832                    .current_dir(self.git_repo.path())
833                    .output();
834
835                return Err(CascadeError::Branch(format!(
836                    "Cherry-pick failed for {} but Git index shows no conflicts. \
837                     This usually means the cherry-pick was aborted or failed in an unexpected way. \
838                     Please try manual resolution.",
839                    &commit_hash[..8]
840                )));
841            }
842
843            return Ok(true);
844        }
845
846        let conflicted_files = self.git_repo.get_conflicted_files()?;
847
848        if conflicted_files.is_empty() {
849            debug!("Conflicted files list is empty");
850            return Ok(true);
851        }
852
853        debug!(
854            "Found conflicts in {} files: {:?}",
855            conflicted_files.len(),
856            conflicted_files
857        );
858
859        // Use the new conflict analyzer for detailed analysis
860        let analysis = self
861            .conflict_analyzer
862            .analyze_conflicts(&conflicted_files, self.git_repo.path())?;
863
864        debug!(
865            "Conflict analysis: {} total conflicts, {} auto-resolvable",
866            analysis.total_conflicts, analysis.auto_resolvable_count
867        );
868
869        // Display recommendations
870        for recommendation in &analysis.recommendations {
871            debug!("{}", recommendation);
872        }
873
874        let mut resolved_count = 0;
875        let mut resolved_files = Vec::new(); // Track which files were actually resolved
876        let mut failed_files = Vec::new();
877
878        for file_analysis in &analysis.files {
879            debug!(
880                "Processing file: {} (auto_resolvable: {}, conflicts: {})",
881                file_analysis.file_path,
882                file_analysis.auto_resolvable,
883                file_analysis.conflicts.len()
884            );
885
886            if file_analysis.auto_resolvable {
887                match self.resolve_file_conflicts_enhanced(
888                    &file_analysis.file_path,
889                    &file_analysis.conflicts,
890                ) {
891                    Ok(ConflictResolution::Resolved) => {
892                        resolved_count += 1;
893                        resolved_files.push(file_analysis.file_path.clone());
894                        debug!("Successfully resolved {}", file_analysis.file_path);
895                    }
896                    Ok(ConflictResolution::TooComplex) => {
897                        debug!(
898                            "{} too complex for auto-resolution",
899                            file_analysis.file_path
900                        );
901                        failed_files.push(file_analysis.file_path.clone());
902                    }
903                    Err(e) => {
904                        debug!("Failed to resolve {}: {}", file_analysis.file_path, e);
905                        failed_files.push(file_analysis.file_path.clone());
906                    }
907                }
908            } else {
909                failed_files.push(file_analysis.file_path.clone());
910                debug!(
911                    "{} requires manual resolution ({} conflicts)",
912                    file_analysis.file_path,
913                    file_analysis.conflicts.len()
914                );
915            }
916        }
917
918        if resolved_count > 0 {
919            debug!(
920                "Resolved {}/{} files",
921                resolved_count,
922                conflicted_files.len()
923            );
924            debug!("Resolved files: {:?}", resolved_files);
925
926            // CRITICAL: Only stage files that were successfully resolved
927            // This prevents staging files that still have conflict markers
928            let file_paths: Vec<&str> = resolved_files.iter().map(|s| s.as_str()).collect();
929            debug!("Staging {} files", file_paths.len());
930            self.git_repo.stage_files(&file_paths)?;
931            debug!("Files staged successfully");
932        } else {
933            debug!("No files were resolved (resolved_count = 0)");
934        }
935
936        // Return true only if ALL conflicts were resolved
937        let all_resolved = failed_files.is_empty();
938
939        debug!(
940            "all_resolved = {}, failed_files = {:?}",
941            all_resolved, failed_files
942        );
943
944        if !all_resolved {
945            debug!("{} files still need manual resolution", failed_files.len());
946        }
947
948        debug!("Returning all_resolved = {}", all_resolved);
949        Ok(all_resolved)
950    }
951
952    /// Resolve conflicts using enhanced analysis
953    fn resolve_file_conflicts_enhanced(
954        &self,
955        file_path: &str,
956        conflicts: &[crate::git::ConflictRegion],
957    ) -> Result<ConflictResolution> {
958        let repo_path = self.git_repo.path();
959        let full_path = repo_path.join(file_path);
960
961        // Read the file content with conflict markers
962        let mut content = std::fs::read_to_string(&full_path)
963            .map_err(|e| CascadeError::config(format!("Failed to read file {file_path}: {e}")))?;
964
965        if conflicts.is_empty() {
966            return Ok(ConflictResolution::Resolved);
967        }
968
969        info!(
970            "Resolving {} conflicts in {} using enhanced analysis",
971            conflicts.len(),
972            file_path
973        );
974
975        let mut any_resolved = false;
976
977        // Process conflicts in reverse order to maintain string indices
978        for conflict in conflicts.iter().rev() {
979            match self.resolve_single_conflict_enhanced(conflict) {
980                Ok(Some(resolution)) => {
981                    // Replace the conflict region with the resolved content
982                    let before = &content[..conflict.start_pos];
983                    let after = &content[conflict.end_pos..];
984                    content = format!("{before}{resolution}{after}");
985                    any_resolved = true;
986                    debug!(
987                        "โœ… Resolved {} conflict at lines {}-{} in {}",
988                        format!("{:?}", conflict.conflict_type).to_lowercase(),
989                        conflict.start_line,
990                        conflict.end_line,
991                        file_path
992                    );
993                }
994                Ok(None) => {
995                    debug!(
996                        "โš ๏ธ  {} conflict at lines {}-{} in {} requires manual resolution",
997                        format!("{:?}", conflict.conflict_type).to_lowercase(),
998                        conflict.start_line,
999                        conflict.end_line,
1000                        file_path
1001                    );
1002                    return Ok(ConflictResolution::TooComplex);
1003                }
1004                Err(e) => {
1005                    debug!("โŒ Failed to resolve conflict in {}: {}", file_path, e);
1006                    return Ok(ConflictResolution::TooComplex);
1007                }
1008            }
1009        }
1010
1011        if any_resolved {
1012            // Check if we resolved ALL conflicts in this file
1013            let remaining_conflicts = self.parse_conflict_markers(&content)?;
1014
1015            if remaining_conflicts.is_empty() {
1016                debug!(
1017                    "All conflicts resolved in {}, content length: {} bytes",
1018                    file_path,
1019                    content.len()
1020                );
1021
1022                // CRITICAL SAFETY CHECK: Don't write empty files!
1023                if content.trim().is_empty() {
1024                    warn!(
1025                        "SAFETY CHECK: Resolved content for {} is empty! Aborting auto-resolution.",
1026                        file_path
1027                    );
1028                    return Ok(ConflictResolution::TooComplex);
1029                }
1030
1031                // SAFETY: Create backup before writing resolved content
1032                let backup_path = full_path.with_extension("cascade-backup");
1033                if let Ok(original_content) = std::fs::read_to_string(&full_path) {
1034                    debug!(
1035                        "Backup for {} (original: {} bytes, resolved: {} bytes)",
1036                        file_path,
1037                        original_content.len(),
1038                        content.len()
1039                    );
1040                    let _ = std::fs::write(&backup_path, original_content);
1041                }
1042
1043                // All conflicts resolved - write the file back atomically
1044                crate::utils::atomic_file::write_string(&full_path, &content)?;
1045
1046                debug!("Wrote {} bytes to {}", content.len(), file_path);
1047                return Ok(ConflictResolution::Resolved);
1048            } else {
1049                info!(
1050                    "Partially resolved conflicts in {} ({} remaining)",
1051                    file_path,
1052                    remaining_conflicts.len()
1053                );
1054            }
1055        }
1056
1057        Ok(ConflictResolution::TooComplex)
1058    }
1059
1060    /// Helper to count whitespace consistency (lower is better)
1061    #[allow(dead_code)]
1062    fn count_whitespace_consistency(content: &str) -> usize {
1063        let mut inconsistencies = 0;
1064        let lines: Vec<&str> = content.lines().collect();
1065
1066        for line in &lines {
1067            // Check for mixed tabs and spaces
1068            if line.contains('\t') && line.contains(' ') {
1069                inconsistencies += 1;
1070            }
1071        }
1072
1073        // Penalize for inconsistencies
1074        lines.len().saturating_sub(inconsistencies)
1075    }
1076
1077    /// Resolve a single conflict using enhanced analysis
1078    fn resolve_single_conflict_enhanced(
1079        &self,
1080        conflict: &crate::git::ConflictRegion,
1081    ) -> Result<Option<String>> {
1082        debug!(
1083            "Resolving {} conflict in {} (lines {}-{})",
1084            format!("{:?}", conflict.conflict_type).to_lowercase(),
1085            conflict.file_path,
1086            conflict.start_line,
1087            conflict.end_line
1088        );
1089
1090        use crate::git::ConflictType;
1091
1092        match conflict.conflict_type {
1093            ConflictType::Whitespace => {
1094                // SAFETY: Only resolve if the content is truly identical except for whitespace
1095                // Otherwise, it might be intentional formatting changes
1096                let our_normalized = conflict
1097                    .our_content
1098                    .split_whitespace()
1099                    .collect::<Vec<_>>()
1100                    .join(" ");
1101                let their_normalized = conflict
1102                    .their_content
1103                    .split_whitespace()
1104                    .collect::<Vec<_>>()
1105                    .join(" ");
1106
1107                if our_normalized == their_normalized {
1108                    // Content is identical - in cherry-pick context, ALWAYS prefer THEIRS
1109                    // CRITICAL: In cherry-pick, OURS=base branch, THEIRS=commit being applied
1110                    // We must keep the commit's changes (THEIRS), not the base (OURS)
1111                    // Otherwise we delete the user's code!
1112                    Ok(Some(conflict.their_content.clone()))
1113                } else {
1114                    // Content differs beyond whitespace - not safe to auto-resolve
1115                    debug!(
1116                        "Whitespace conflict has content differences - requires manual resolution"
1117                    );
1118                    Ok(None)
1119                }
1120            }
1121            ConflictType::LineEnding => {
1122                // Normalize to Unix line endings
1123                let normalized = conflict
1124                    .our_content
1125                    .replace("\r\n", "\n")
1126                    .replace('\r', "\n");
1127                Ok(Some(normalized))
1128            }
1129            ConflictType::PureAddition => {
1130                // CRITICAL: In cherry-pick, OURS=base, THEIRS=commit being applied
1131                // We must respect what the commit does (THEIRS), not what the base has (OURS)
1132
1133                if conflict.our_content.is_empty() && !conflict.their_content.is_empty() {
1134                    // Base is empty, commit adds content โ†’ keep the addition
1135                    Ok(Some(conflict.their_content.clone()))
1136                } else if conflict.their_content.is_empty() && !conflict.our_content.is_empty() {
1137                    // Base has content, commit removes it โ†’ keep it removed (empty)
1138                    Ok(Some(String::new()))
1139                } else if conflict.our_content.is_empty() && conflict.their_content.is_empty() {
1140                    // Both empty โ†’ keep empty
1141                    Ok(Some(String::new()))
1142                } else {
1143                    // Both sides have content - this could be:
1144                    // - Duplicate function definitions
1145                    // - Conflicting logic
1146                    // - Different implementations of same feature
1147                    // Too risky to auto-merge - require manual resolution
1148                    debug!(
1149                        "PureAddition conflict has content on both sides - requires manual resolution"
1150                    );
1151                    Ok(None)
1152                }
1153            }
1154            ConflictType::ImportMerge => {
1155                // SAFETY: Only merge simple single-line imports
1156                // Multi-line imports or complex cases require manual resolution
1157
1158                // Check if all imports are single-line and look like imports
1159                let our_lines: Vec<&str> = conflict.our_content.lines().collect();
1160                let their_lines: Vec<&str> = conflict.their_content.lines().collect();
1161
1162                // Verify all lines look like simple imports (heuristic check)
1163                let all_simple = our_lines.iter().chain(their_lines.iter()).all(|line| {
1164                    let trimmed = line.trim();
1165                    trimmed.starts_with("import ")
1166                        || trimmed.starts_with("from ")
1167                        || trimmed.starts_with("use ")
1168                        || trimmed.starts_with("#include")
1169                        || trimmed.is_empty()
1170                });
1171
1172                if !all_simple {
1173                    debug!("ImportMerge contains non-import lines - requires manual resolution");
1174                    return Ok(None);
1175                }
1176
1177                // Merge and deduplicate imports
1178                let mut all_imports: Vec<&str> = our_lines
1179                    .into_iter()
1180                    .chain(their_lines)
1181                    .filter(|line| !line.trim().is_empty())
1182                    .collect();
1183                all_imports.sort();
1184                all_imports.dedup();
1185                Ok(Some(all_imports.join("\n")))
1186            }
1187            ConflictType::Structural | ConflictType::ContentOverlap | ConflictType::Complex => {
1188                // These require manual resolution
1189                Ok(None)
1190            }
1191        }
1192    }
1193
1194    /// Parse conflict markers from file content
1195    fn parse_conflict_markers(&self, content: &str) -> Result<Vec<ConflictRegion>> {
1196        let lines: Vec<&str> = content.lines().collect();
1197        let mut conflicts = Vec::new();
1198        let mut i = 0;
1199
1200        while i < lines.len() {
1201            if lines[i].starts_with("<<<<<<<") {
1202                // Found start of conflict
1203                let start_line = i + 1;
1204                let mut separator_line = None;
1205                let mut end_line = None;
1206
1207                // Find the separator and end
1208                for (j, line) in lines.iter().enumerate().skip(i + 1) {
1209                    if line.starts_with("=======") {
1210                        separator_line = Some(j + 1);
1211                    } else if line.starts_with(">>>>>>>") {
1212                        end_line = Some(j + 1);
1213                        break;
1214                    }
1215                }
1216
1217                if let (Some(sep), Some(end)) = (separator_line, end_line) {
1218                    // Calculate byte positions
1219                    let start_pos = lines[..i].iter().map(|l| l.len() + 1).sum::<usize>();
1220                    let end_pos = lines[..end].iter().map(|l| l.len() + 1).sum::<usize>();
1221
1222                    let our_content = lines[(i + 1)..(sep - 1)].join("\n");
1223                    let their_content = lines[sep..(end - 1)].join("\n");
1224
1225                    conflicts.push(ConflictRegion {
1226                        start: start_pos,
1227                        end: end_pos,
1228                        start_line,
1229                        end_line: end,
1230                        our_content,
1231                        their_content,
1232                    });
1233
1234                    i = end;
1235                } else {
1236                    i += 1;
1237                }
1238            } else {
1239                i += 1;
1240            }
1241        }
1242
1243        Ok(conflicts)
1244    }
1245
1246    /// Update a stack entry with new commit information
1247    /// NOTE: We keep the original branch name to preserve PR mapping, only update commit hash
1248    fn update_stack_entry(
1249        &mut self,
1250        stack_id: Uuid,
1251        entry_id: &Uuid,
1252        _new_branch: &str,
1253        new_commit_hash: &str,
1254    ) -> Result<()> {
1255        debug!(
1256            "Updating entry {} in stack {} with new commit {}",
1257            entry_id, stack_id, new_commit_hash
1258        );
1259
1260        // Get the stack and update the entry
1261        let stack = self
1262            .stack_manager
1263            .get_stack_mut(&stack_id)
1264            .ok_or_else(|| CascadeError::config(format!("Stack {stack_id} not found")))?;
1265
1266        // Find and update the entry
1267        if let Some(entry) = stack.entries.iter_mut().find(|e| e.id == *entry_id) {
1268            debug!(
1269                "Found entry {} - updating commit from '{}' to '{}' (keeping original branch '{}')",
1270                entry_id, entry.commit_hash, new_commit_hash, entry.branch
1271            );
1272
1273            // CRITICAL: Keep the original branch name to preserve PR mapping
1274            // Only update the commit hash to point to the new rebased commit
1275            entry.commit_hash = new_commit_hash.to_string();
1276
1277            // Note: Stack will be saved by the caller (StackManager) after rebase completes
1278
1279            debug!(
1280                "Successfully updated entry {} in stack {}",
1281                entry_id, stack_id
1282            );
1283            Ok(())
1284        } else {
1285            Err(CascadeError::config(format!(
1286                "Entry {entry_id} not found in stack {stack_id}"
1287            )))
1288        }
1289    }
1290
1291    /// Pull latest changes from remote
1292    fn pull_latest_changes(&self, branch: &str) -> Result<()> {
1293        info!("Pulling latest changes for branch {}", branch);
1294
1295        // First try to fetch (this might fail if no remote exists)
1296        match self.git_repo.fetch() {
1297            Ok(_) => {
1298                debug!("Fetch successful");
1299                // Now try to pull the specific branch
1300                match self.git_repo.pull(branch) {
1301                    Ok(_) => {
1302                        info!("Pull completed successfully for {}", branch);
1303                        Ok(())
1304                    }
1305                    Err(e) => {
1306                        warn!("Pull failed for {}: {}", branch, e);
1307                        // Don't fail the entire rebase for pull issues
1308                        Ok(())
1309                    }
1310                }
1311            }
1312            Err(e) => {
1313                warn!("Fetch failed: {}", e);
1314                // Don't fail if there's no remote configured
1315                Ok(())
1316            }
1317        }
1318    }
1319
1320    /// Check if rebase is in progress
1321    pub fn is_rebase_in_progress(&self) -> bool {
1322        // Check for git rebase state files
1323        let git_dir = self.git_repo.path().join(".git");
1324        git_dir.join("REBASE_HEAD").exists()
1325            || git_dir.join("rebase-merge").exists()
1326            || git_dir.join("rebase-apply").exists()
1327    }
1328
1329    /// Abort an in-progress rebase
1330    pub fn abort_rebase(&self) -> Result<()> {
1331        info!("Aborting rebase operation");
1332
1333        let git_dir = self.git_repo.path().join(".git");
1334
1335        // Clean up rebase state files
1336        if git_dir.join("REBASE_HEAD").exists() {
1337            std::fs::remove_file(git_dir.join("REBASE_HEAD")).map_err(|e| {
1338                CascadeError::Git(git2::Error::from_str(&format!(
1339                    "Failed to clean rebase state: {e}"
1340                )))
1341            })?;
1342        }
1343
1344        if git_dir.join("rebase-merge").exists() {
1345            std::fs::remove_dir_all(git_dir.join("rebase-merge")).map_err(|e| {
1346                CascadeError::Git(git2::Error::from_str(&format!(
1347                    "Failed to clean rebase-merge: {e}"
1348                )))
1349            })?;
1350        }
1351
1352        if git_dir.join("rebase-apply").exists() {
1353            std::fs::remove_dir_all(git_dir.join("rebase-apply")).map_err(|e| {
1354                CascadeError::Git(git2::Error::from_str(&format!(
1355                    "Failed to clean rebase-apply: {e}"
1356                )))
1357            })?;
1358        }
1359
1360        info!("Rebase aborted successfully");
1361        Ok(())
1362    }
1363
1364    /// Continue an in-progress rebase after conflict resolution
1365    pub fn continue_rebase(&self) -> Result<()> {
1366        info!("Continuing rebase operation");
1367
1368        // Check if there are still conflicts
1369        if self.git_repo.has_conflicts()? {
1370            return Err(CascadeError::branch(
1371                "Cannot continue rebase: there are unresolved conflicts. Resolve conflicts and stage files first.".to_string()
1372            ));
1373        }
1374
1375        // Stage resolved files
1376        self.git_repo.stage_conflict_resolved_files()?;
1377
1378        info!("Rebase continued successfully");
1379        Ok(())
1380    }
1381
1382    /// Check if there's an in-progress cherry-pick operation
1383    fn has_in_progress_cherry_pick(&self) -> Result<bool> {
1384        let git_dir = self.git_repo.path().join(".git");
1385        Ok(git_dir.join("CHERRY_PICK_HEAD").exists())
1386    }
1387
1388    /// Handle resuming an in-progress cherry-pick from a previous failed sync
1389    fn handle_in_progress_cherry_pick(&mut self, stack: &Stack) -> Result<RebaseResult> {
1390        use crate::cli::output::Output;
1391
1392        let git_dir = self.git_repo.path().join(".git");
1393
1394        Output::section("Resuming in-progress sync");
1395        println!();
1396        Output::info("Detected unfinished cherry-pick from previous sync");
1397        println!();
1398
1399        // Check if conflicts are resolved
1400        if self.git_repo.has_conflicts()? {
1401            let conflicted_files = self.git_repo.get_conflicted_files()?;
1402
1403            let result = RebaseResult {
1404                success: false,
1405                branch_mapping: HashMap::new(),
1406                conflicts: conflicted_files.clone(),
1407                new_commits: Vec::new(),
1408                error: Some(format!(
1409                    "Cannot continue: {} file(s) still have unresolved conflicts\n\n\
1410                    MANUAL CONFLICT RESOLUTION REQUIRED\n\
1411                    =====================================\n\n\
1412                    Conflicted files:\n{}\n\n\
1413                    Step 1: Analyze conflicts\n\
1414                    โ†’ Run: ca conflicts\n\
1415                    โ†’ Shows detailed conflict analysis\n\n\
1416                    Step 2: Resolve conflicts in your editor\n\
1417                    โ†’ Open conflicted files and edit them\n\
1418                    โ†’ Remove conflict markers (<<<<<<, ======, >>>>>>)\n\
1419                    โ†’ Keep the code you want\n\
1420                    โ†’ Save the files\n\n\
1421                    Step 3: Mark conflicts as resolved\n\
1422                    โ†’ Run: git add <resolved-files>\n\
1423                    โ†’ Or: git add -A (to stage all resolved files)\n\n\
1424                    Step 4: Complete the sync\n\
1425                    โ†’ Run: ca sync\n\
1426                    โ†’ Cascade will continue from where it left off\n\n\
1427                    Alternative: Abort and start over\n\
1428                    โ†’ Run: git cherry-pick --abort\n\
1429                    โ†’ Then: ca sync (starts fresh)",
1430                    conflicted_files.len(),
1431                    conflicted_files
1432                        .iter()
1433                        .map(|f| format!("  - {}", f))
1434                        .collect::<Vec<_>>()
1435                        .join("\n")
1436                )),
1437                summary: "Sync paused - conflicts need resolution".to_string(),
1438            };
1439
1440            return Ok(result);
1441        }
1442
1443        // Conflicts are resolved - continue the cherry-pick
1444        Output::info("Conflicts resolved, continuing cherry-pick...");
1445
1446        // Stage all resolved files
1447        self.git_repo.stage_conflict_resolved_files()?;
1448
1449        // Complete the cherry-pick by committing
1450        let cherry_pick_msg_file = git_dir.join("CHERRY_PICK_MSG");
1451        let commit_message = if cherry_pick_msg_file.exists() {
1452            std::fs::read_to_string(&cherry_pick_msg_file)
1453                .unwrap_or_else(|_| "Resolved conflicts".to_string())
1454        } else {
1455            "Resolved conflicts".to_string()
1456        };
1457
1458        match self.git_repo.commit(&commit_message) {
1459            Ok(_new_commit_id) => {
1460                Output::success("Cherry-pick completed");
1461
1462                // Clean up cherry-pick state
1463                if git_dir.join("CHERRY_PICK_HEAD").exists() {
1464                    let _ = std::fs::remove_file(git_dir.join("CHERRY_PICK_HEAD"));
1465                }
1466                if cherry_pick_msg_file.exists() {
1467                    let _ = std::fs::remove_file(&cherry_pick_msg_file);
1468                }
1469
1470                println!();
1471                Output::info("Continuing with rest of stack...");
1472                println!();
1473
1474                // Now continue with the rest of the rebase
1475                // We need to restart the full rebase since we don't track which entry we were on
1476                self.rebase_with_force_push(stack)
1477            }
1478            Err(e) => {
1479                let result = RebaseResult {
1480                    success: false,
1481                    branch_mapping: HashMap::new(),
1482                    conflicts: Vec::new(),
1483                    new_commits: Vec::new(),
1484                    error: Some(format!(
1485                        "Failed to complete cherry-pick: {}\n\n\
1486                        This usually means:\n\
1487                        - Git index is locked (another process accessing repo)\n\
1488                        - File permissions issue\n\
1489                        - Disk space issue\n\n\
1490                        Recovery:\n\
1491                        1. Check if another Git operation is running\n\
1492                        2. Run 'rm -f .git/index.lock' if stale lock exists\n\
1493                        3. Run 'git status' to check repo state\n\
1494                        4. Retry 'ca sync' after fixing the issue\n\n\
1495                        Or abort and start fresh:\n\
1496                        โ†’ Run: git cherry-pick --abort\n\
1497                        โ†’ Then: ca sync",
1498                        e
1499                    )),
1500                    summary: "Failed to complete cherry-pick".to_string(),
1501                };
1502
1503                Ok(result)
1504            }
1505        }
1506    }
1507}
1508
1509impl RebaseResult {
1510    /// Get a summary of the rebase operation
1511    pub fn get_summary(&self) -> String {
1512        if self.success {
1513            format!("โœ… {}", self.summary)
1514        } else {
1515            format!(
1516                "โŒ Rebase failed: {}",
1517                self.error.as_deref().unwrap_or("Unknown error")
1518            )
1519        }
1520    }
1521
1522    /// Check if any conflicts occurred
1523    pub fn has_conflicts(&self) -> bool {
1524        !self.conflicts.is_empty()
1525    }
1526
1527    /// Get the number of successful operations
1528    pub fn success_count(&self) -> usize {
1529        self.new_commits.len()
1530    }
1531}
1532
1533#[cfg(test)]
1534mod tests {
1535    use super::*;
1536    use std::path::PathBuf;
1537    use std::process::Command;
1538    use tempfile::TempDir;
1539
1540    #[allow(dead_code)]
1541    fn create_test_repo() -> (TempDir, PathBuf) {
1542        let temp_dir = TempDir::new().unwrap();
1543        let repo_path = temp_dir.path().to_path_buf();
1544
1545        // Initialize git repository
1546        Command::new("git")
1547            .args(["init"])
1548            .current_dir(&repo_path)
1549            .output()
1550            .unwrap();
1551        Command::new("git")
1552            .args(["config", "user.name", "Test"])
1553            .current_dir(&repo_path)
1554            .output()
1555            .unwrap();
1556        Command::new("git")
1557            .args(["config", "user.email", "test@test.com"])
1558            .current_dir(&repo_path)
1559            .output()
1560            .unwrap();
1561
1562        // Create initial commit
1563        std::fs::write(repo_path.join("README.md"), "# Test").unwrap();
1564        Command::new("git")
1565            .args(["add", "."])
1566            .current_dir(&repo_path)
1567            .output()
1568            .unwrap();
1569        Command::new("git")
1570            .args(["commit", "-m", "Initial"])
1571            .current_dir(&repo_path)
1572            .output()
1573            .unwrap();
1574
1575        (temp_dir, repo_path)
1576    }
1577
1578    #[test]
1579    fn test_conflict_region_creation() {
1580        let region = ConflictRegion {
1581            start: 0,
1582            end: 50,
1583            start_line: 1,
1584            end_line: 3,
1585            our_content: "function test() {\n    return true;\n}".to_string(),
1586            their_content: "function test() {\n  return true;\n}".to_string(),
1587        };
1588
1589        assert_eq!(region.start_line, 1);
1590        assert_eq!(region.end_line, 3);
1591        assert!(region.our_content.contains("return true"));
1592        assert!(region.their_content.contains("return true"));
1593    }
1594
1595    #[test]
1596    fn test_rebase_strategies() {
1597        assert_eq!(RebaseStrategy::ForcePush, RebaseStrategy::ForcePush);
1598        assert_eq!(RebaseStrategy::Interactive, RebaseStrategy::Interactive);
1599    }
1600
1601    #[test]
1602    fn test_rebase_options() {
1603        let options = RebaseOptions::default();
1604        assert_eq!(options.strategy, RebaseStrategy::ForcePush);
1605        assert!(!options.interactive);
1606        assert!(options.auto_resolve);
1607        assert_eq!(options.max_retries, 3);
1608    }
1609
1610    #[test]
1611    fn test_cleanup_guard_tracks_branches() {
1612        let mut guard = TempBranchCleanupGuard::new();
1613        assert!(guard.branches.is_empty());
1614
1615        guard.add_branch("test-branch-1".to_string());
1616        guard.add_branch("test-branch-2".to_string());
1617
1618        assert_eq!(guard.branches.len(), 2);
1619        assert_eq!(guard.branches[0], "test-branch-1");
1620        assert_eq!(guard.branches[1], "test-branch-2");
1621    }
1622
1623    #[test]
1624    fn test_cleanup_guard_prevents_double_cleanup() {
1625        use std::process::Command;
1626        use tempfile::TempDir;
1627
1628        // Create a temporary git repo
1629        let temp_dir = TempDir::new().unwrap();
1630        let repo_path = temp_dir.path();
1631
1632        Command::new("git")
1633            .args(["init"])
1634            .current_dir(repo_path)
1635            .output()
1636            .unwrap();
1637
1638        Command::new("git")
1639            .args(["config", "user.name", "Test"])
1640            .current_dir(repo_path)
1641            .output()
1642            .unwrap();
1643
1644        Command::new("git")
1645            .args(["config", "user.email", "test@test.com"])
1646            .current_dir(repo_path)
1647            .output()
1648            .unwrap();
1649
1650        // Create initial commit
1651        std::fs::write(repo_path.join("test.txt"), "test").unwrap();
1652        Command::new("git")
1653            .args(["add", "."])
1654            .current_dir(repo_path)
1655            .output()
1656            .unwrap();
1657        Command::new("git")
1658            .args(["commit", "-m", "initial"])
1659            .current_dir(repo_path)
1660            .output()
1661            .unwrap();
1662
1663        let git_repo = GitRepository::open(repo_path).unwrap();
1664
1665        // Create a test branch
1666        git_repo.create_branch("test-temp", None).unwrap();
1667
1668        let mut guard = TempBranchCleanupGuard::new();
1669        guard.add_branch("test-temp".to_string());
1670
1671        // First cleanup should work
1672        guard.cleanup(&git_repo);
1673        assert!(guard.cleaned);
1674
1675        // Second cleanup should be a no-op (shouldn't panic)
1676        guard.cleanup(&git_repo);
1677        assert!(guard.cleaned);
1678    }
1679
1680    #[test]
1681    fn test_rebase_result() {
1682        let result = RebaseResult {
1683            success: true,
1684            branch_mapping: std::collections::HashMap::new(),
1685            conflicts: vec!["abc123".to_string()],
1686            new_commits: vec!["def456".to_string()],
1687            error: None,
1688            summary: "Test summary".to_string(),
1689        };
1690
1691        assert!(result.success);
1692        assert!(result.has_conflicts());
1693        assert_eq!(result.success_count(), 1);
1694    }
1695}