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        println!(); // Spacing before tree
269        let plural = if entry_count == 1 { "entry" } else { "entries" };
270        println!("Rebasing {} {}...", entry_count, plural);
271
272        // Phase 1: Rebase all entries locally (libgit2 only - no CLI commands)
273        for (index, entry) in stack.entries.iter().enumerate() {
274            let original_branch = &entry.branch;
275
276            // Create a temporary branch from the current base
277            // This avoids committing directly to protected branches like develop/main
278            let temp_branch = format!("{}-temp-{}", original_branch, Utc::now().timestamp());
279            temp_branches.push(temp_branch.clone()); // Track for cleanup
280            self.git_repo
281                .create_branch(&temp_branch, Some(&current_base))?;
282            self.git_repo.checkout_branch(&temp_branch)?;
283
284            // Cherry-pick the commit onto the temp branch (NOT the protected base!)
285            match self.cherry_pick_commit(&entry.commit_hash) {
286                Ok(new_commit_hash) => {
287                    result.new_commits.push(new_commit_hash.clone());
288
289                    // Get the commit that's now at HEAD (the cherry-picked commit)
290                    let rebased_commit_id = self.git_repo.get_head_commit()?.id().to_string();
291
292                    // Update the original branch to point to this rebased commit
293                    // This is LOCAL ONLY - moves refs/heads/<branch> to the commit on temp branch
294                    self.git_repo
295                        .update_branch_to_commit(original_branch, &rebased_commit_id)?;
296
297                    // Track which branches need to be pushed (only those with PRs)
298                    let tree_char = if index + 1 == entry_count {
299                        "โ””โ”€"
300                    } else {
301                        "โ”œโ”€"
302                    };
303
304                    if let Some(pr_num) = &entry.pull_request_id {
305                        println!("   {} {} (PR #{})", tree_char, original_branch, pr_num);
306                        branches_to_push.push((original_branch.clone(), pr_num.clone()));
307                    } else {
308                        println!("   {} {} (not submitted)", tree_char, original_branch);
309                    }
310
311                    result
312                        .branch_mapping
313                        .insert(original_branch.clone(), original_branch.clone());
314
315                    // Update stack entry with new commit hash
316                    self.update_stack_entry(
317                        stack.id,
318                        &entry.id,
319                        original_branch,
320                        &rebased_commit_id,
321                    )?;
322
323                    // This branch becomes the base for the next entry
324                    current_base = original_branch.clone();
325                }
326                Err(e) => {
327                    println!(); // Spacing before error
328                    Output::error(format!("Conflict in {}: {}", &entry.commit_hash[..8], e));
329                    result.conflicts.push(entry.commit_hash.clone());
330
331                    if !self.options.auto_resolve {
332                        result.success = false;
333                        result.error = Some(format!(
334                            "Conflict in {}: {}\n\n\
335                            MANUAL CONFLICT RESOLUTION REQUIRED\n\
336                            =====================================\n\n\
337                            Step 1: Analyze conflicts\n\
338                            โ†’ Run: ca conflicts\n\
339                            โ†’ This shows which conflicts are in which files\n\n\
340                            Step 2: Resolve conflicts in your editor\n\
341                            โ†’ Open conflicted files and edit them\n\
342                            โ†’ Remove conflict markers (<<<<<<, ======, >>>>>>)\n\
343                            โ†’ Keep the code you want\n\
344                            โ†’ Save the files\n\n\
345                            Step 3: Mark conflicts as resolved\n\
346                            โ†’ Run: git add <resolved-files>\n\
347                            โ†’ Or: git add -A (to stage all resolved files)\n\n\
348                            Step 4: Complete the sync\n\
349                            โ†’ Run: ca sync\n\
350                            โ†’ Cascade will detect resolved conflicts and continue\n\n\
351                            Alternative: Abort and start over\n\
352                            โ†’ Run: git cherry-pick --abort\n\
353                            โ†’ Then: ca sync (starts fresh)\n\n\
354                            TIP: Enable auto-resolution for simple conflicts:\n\
355                            โ†’ Run: ca sync --auto-resolve\n\
356                            โ†’ Only complex conflicts will require manual resolution",
357                            entry.commit_hash, e
358                        ));
359                        break;
360                    }
361
362                    // Try to resolve automatically
363                    match self.auto_resolve_conflicts(&entry.commit_hash) {
364                        Ok(fully_resolved) => {
365                            if !fully_resolved {
366                                result.success = false;
367                                result.error = Some(format!(
368                                    "Could not auto-resolve all conflicts in {}\n\n\
369                                    MANUAL CONFLICT RESOLUTION REQUIRED\n\
370                                    =====================================\n\n\
371                                    Some conflicts are too complex for auto-resolution.\n\n\
372                                    Step 1: Analyze remaining conflicts\n\
373                                    โ†’ Run: ca conflicts\n\
374                                    โ†’ Shows which files still have conflicts\n\
375                                    โ†’ Use --detailed flag for more info\n\n\
376                                    Step 2: Resolve conflicts in your editor\n\
377                                    โ†’ Open conflicted files (marked with โœ‹ in ca conflicts output)\n\
378                                    โ†’ Remove conflict markers (<<<<<<, ======, >>>>>>)\n\
379                                    โ†’ Keep the code you want\n\
380                                    โ†’ Save the files\n\n\
381                                    Step 3: Mark conflicts as resolved\n\
382                                    โ†’ Run: git add <resolved-files>\n\
383                                    โ†’ Or: git add -A (to stage all resolved files)\n\n\
384                                    Step 4: Complete the sync\n\
385                                    โ†’ Run: ca sync\n\
386                                    โ†’ Cascade will continue from where it left off\n\n\
387                                    Alternative: Abort and start over\n\
388                                    โ†’ Run: git cherry-pick --abort\n\
389                                    โ†’ Then: ca sync (starts fresh)\n\n\
390                                    BACKUP: If auto-resolution was wrong\n\
391                                    โ†’ Check for .cascade-backup files in your repo\n\
392                                    โ†’ These contain the original file content before auto-resolution",
393                                    &entry.commit_hash[..8]
394                                ));
395                                break;
396                            }
397
398                            // Commit the resolved changes
399                            let commit_message =
400                                format!("Auto-resolved conflicts in {}", &entry.commit_hash[..8]);
401                            
402                            // DEBUG: Check what's staged before committing
403                            warn!("AUTO-RESOLVE DEBUG: About to commit. Checking staged files...");
404                            if let Ok(status) = std::process::Command::new("git")
405                                .args(["diff", "--cached", "--stat"])
406                                .current_dir(self.git_repo.path())
407                                .output()
408                            {
409                                let stat_output = String::from_utf8_lossy(&status.stdout);
410                                warn!("AUTO-RESOLVE DEBUG: Staged changes:\n{}", stat_output);
411                            }
412                            
413                            match self.git_repo.commit(&commit_message) {
414                                Ok(new_commit_id) => {
415                                    warn!(
416                                        "AUTO-RESOLVE DEBUG: Created commit {} with message '{}'",
417                                        &new_commit_id[..8],
418                                        commit_message
419                                    );
420                                    
421                                    // DEBUG: Check what's in the commit
422                                    if let Ok(show) = std::process::Command::new("git")
423                                        .args(["show", "--stat", &new_commit_id])
424                                        .current_dir(self.git_repo.path())
425                                        .output()
426                                    {
427                                        let show_output = String::from_utf8_lossy(&show.stdout);
428                                        warn!("AUTO-RESOLVE DEBUG: Commit contents:\n{}", show_output);
429                                    }
430                                    
431                                    Output::success("Auto-resolved conflicts");
432                                    result.new_commits.push(new_commit_id.clone());
433                                    let rebased_commit_id = new_commit_id;
434
435                                    // Update the original branch to point to this rebased commit
436                                    self.git_repo.update_branch_to_commit(
437                                        original_branch,
438                                        &rebased_commit_id,
439                                    )?;
440
441                                    // Track which branches need to be pushed (only those with PRs)
442                                    let tree_char = if index + 1 == entry_count {
443                                        "โ””โ”€"
444                                    } else {
445                                        "โ”œโ”€"
446                                    };
447
448                                    if let Some(pr_num) = &entry.pull_request_id {
449                                        println!(
450                                            "   {} {} (PR #{})",
451                                            tree_char, original_branch, pr_num
452                                        );
453                                        branches_to_push
454                                            .push((original_branch.clone(), pr_num.clone()));
455                                    } else {
456                                        println!(
457                                            "   {} {} (not submitted)",
458                                            tree_char, original_branch
459                                        );
460                                    }
461
462                                    result
463                                        .branch_mapping
464                                        .insert(original_branch.clone(), original_branch.clone());
465
466                                    // Update stack entry with new commit hash
467                                    self.update_stack_entry(
468                                        stack.id,
469                                        &entry.id,
470                                        original_branch,
471                                        &rebased_commit_id,
472                                    )?;
473
474                                    // This branch becomes the base for the next entry
475                                    current_base = original_branch.clone();
476                                }
477                                Err(commit_err) => {
478                                    result.success = false;
479                                    result.error = Some(format!(
480                                        "Could not commit auto-resolved conflicts: {}\n\n\
481                                        This usually means:\n\
482                                        - Git index is locked (another process accessing repo)\n\
483                                        - File permissions issue\n\
484                                        - Disk space issue\n\n\
485                                        Recovery:\n\
486                                        1. Check if another Git operation is running\n\
487                                        2. Run 'rm -f .git/index.lock' if stale lock exists\n\
488                                        3. Run 'git status' to check repo state\n\
489                                        4. Retry 'ca sync' after fixing the issue",
490                                        commit_err
491                                    ));
492                                    break;
493                                }
494                            }
495                        }
496                        Err(resolve_err) => {
497                            result.success = false;
498                            result.error = Some(format!(
499                                "Could not resolve conflicts: {}\n\n\
500                                Recovery:\n\
501                                1. Check repo state: 'git status'\n\
502                                2. If files are staged, commit or reset them: 'git reset --hard HEAD'\n\
503                                3. Remove any lock files: 'rm -f .git/index.lock'\n\
504                                4. Retry 'ca sync'",
505                                resolve_err
506                            ));
507                            break;
508                        }
509                    }
510                }
511            }
512        }
513
514        // Cleanup temp branches before returning to original branch
515        // Must checkout away from temp branches first
516        if !temp_branches.is_empty() {
517            // Force checkout to base branch to allow temp branch deletion
518            // Use unsafe checkout to bypass safety checks since we know this is cleanup
519            if let Err(e) = self.git_repo.checkout_branch_unsafe(&target_base) {
520                Output::warning(format!("Could not checkout base for cleanup: {}", e));
521                // If we can't checkout, we can't delete temp branches
522                // This is non-critical - temp branches will be cleaned up eventually
523            } else {
524                // Successfully checked out - now delete temp branches
525                for temp_branch in &temp_branches {
526                    if let Err(e) = self.git_repo.delete_branch_unsafe(temp_branch) {
527                        debug!("Could not delete temp branch {}: {}", temp_branch, e);
528                    }
529                }
530            }
531        }
532
533        // Phase 2: Push all branches with PRs to remote (git CLI - after all libgit2 operations)
534        // This batch approach prevents index lock conflicts between libgit2 and git CLI
535        let pushed_count = branches_to_push.len();
536        let skipped_count = entry_count - pushed_count;
537
538        if !branches_to_push.is_empty() {
539            println!(); // Spacing before push phase
540            println!(
541                "Pushing {} branch{} to remote...",
542                pushed_count,
543                if pushed_count == 1 { "" } else { "es" }
544            );
545
546            for (branch_name, _pr_num) in &branches_to_push {
547                match self.git_repo.force_push_single_branch_auto(branch_name) {
548                    Ok(_) => {
549                        debug!("Pushed {} successfully", branch_name);
550                    }
551                    Err(e) => {
552                        Output::warning(format!("Could not push '{}': {}", branch_name, e));
553                        // Continue pushing other branches even if one fails
554                    }
555                }
556            }
557        }
558
559        // Update working branch to point to the top of the rebased stack
560        // This ensures subsequent `ca push` doesn't re-add old commits
561        if let Some(ref orig_branch) = original_branch {
562            // CRITICAL: Never update the base branch! Only update working branches
563            if orig_branch != &target_base {
564                // Get the last entry's branch (top of stack)
565                if let Some(last_entry) = stack.entries.last() {
566                    let top_branch = &last_entry.branch;
567
568                    // Force-update working branch to point to same commit as top entry
569                    if let Ok(top_commit) = self.git_repo.get_branch_head(top_branch) {
570                        debug!(
571                            "Updating working branch '{}' to match top of stack ({})",
572                            orig_branch,
573                            &top_commit[..8]
574                        );
575
576                        if let Err(e) = self
577                            .git_repo
578                            .update_branch_to_commit(orig_branch, &top_commit)
579                        {
580                            Output::warning(format!(
581                                "Could not update working branch '{}' to top of stack: {}",
582                                orig_branch, e
583                            ));
584                        }
585                    }
586                }
587
588                // Return to original working branch
589                // Use unsafe checkout to force it (we're in cleanup phase, no uncommitted changes)
590                if let Err(e) = self.git_repo.checkout_branch_unsafe(orig_branch) {
591                    debug!(
592                        "Could not return to original branch '{}': {}",
593                        orig_branch, e
594                    );
595                    // Non-critical: User is left on base branch instead of working branch
596                }
597            } else {
598                // User was on base branch - this is unusual but valid
599                // Don't update base branch, just checkout back to it
600                debug!(
601                    "Skipping working branch update - user was on base branch '{}'",
602                    orig_branch
603                );
604                if let Err(e) = self.git_repo.checkout_branch_unsafe(orig_branch) {
605                    debug!("Could not return to base branch '{}': {}", orig_branch, e);
606                }
607            }
608        }
609
610        // Build summary message
611        result.summary = if pushed_count > 0 {
612            let pr_plural = if pushed_count == 1 { "" } else { "s" };
613            let entry_plural = if entry_count == 1 { "entry" } else { "entries" };
614
615            if skipped_count > 0 {
616                format!(
617                    "{} {} rebased ({} PR{} updated, {} not yet submitted)",
618                    entry_count, entry_plural, pushed_count, pr_plural, skipped_count
619                )
620            } else {
621                format!(
622                    "{} {} rebased ({} PR{} updated)",
623                    entry_count, entry_plural, pushed_count, pr_plural
624                )
625            }
626        } else {
627            let plural = if entry_count == 1 { "entry" } else { "entries" };
628            format!("{} {} rebased (no PRs to update yet)", entry_count, plural)
629        };
630
631        // Display result with proper formatting
632        println!(); // Spacing after tree
633        if result.success {
634            Output::success(&result.summary);
635        } else {
636            Output::error(format!("Rebase failed: {:?}", result.error));
637        }
638
639        // Save the updated stack metadata to disk
640        self.stack_manager.save_to_disk()?;
641
642        Ok(result)
643    }
644
645    /// Interactive rebase with user input
646    fn rebase_interactive(&mut self, stack: &Stack) -> Result<RebaseResult> {
647        info!("Starting interactive rebase for stack '{}'", stack.name);
648
649        let mut result = RebaseResult {
650            success: true,
651            branch_mapping: HashMap::new(),
652            conflicts: Vec::new(),
653            new_commits: Vec::new(),
654            error: None,
655            summary: String::new(),
656        };
657
658        println!("Interactive Rebase for Stack: {}", stack.name);
659        println!("   Base branch: {}", stack.base_branch);
660        println!("   Entries: {}", stack.entries.len());
661
662        if self.options.interactive {
663            println!("\nChoose action for each commit:");
664            println!("  (p)ick   - apply the commit");
665            println!("  (s)kip   - skip this commit");
666            println!("  (e)dit   - edit the commit message");
667            println!("  (q)uit   - abort the rebase");
668        }
669
670        // For now, automatically pick all commits
671        // In a real implementation, this would prompt the user
672        for entry in &stack.entries {
673            println!(
674                "  {} {} - {}",
675                entry.short_hash(),
676                entry.branch,
677                entry.short_message(50)
678            );
679
680            // Auto-pick for demo purposes
681            match self.cherry_pick_commit(&entry.commit_hash) {
682                Ok(new_commit) => result.new_commits.push(new_commit),
683                Err(_) => result.conflicts.push(entry.commit_hash.clone()),
684            }
685        }
686
687        result.summary = format!(
688            "Interactive rebase processed {} commits",
689            stack.entries.len()
690        );
691        Ok(result)
692    }
693
694    /// Cherry-pick a commit onto the current branch
695    fn cherry_pick_commit(&self, commit_hash: &str) -> Result<String> {
696        // Use the real cherry-pick implementation from GitRepository
697        let new_commit_hash = self.git_repo.cherry_pick(commit_hash)?;
698
699        // Check for any leftover staged changes after successful cherry-pick
700        if let Ok(staged_files) = self.git_repo.get_staged_files() {
701            if !staged_files.is_empty() {
702                // Commit any leftover staged changes silently
703                let cleanup_message = format!("Cleanup after cherry-pick {}", &commit_hash[..8]);
704                let _ = self.git_repo.commit_staged_changes(&cleanup_message);
705            }
706        }
707
708        Ok(new_commit_hash)
709    }
710
711    /// Attempt to automatically resolve conflicts
712    fn auto_resolve_conflicts(&self, commit_hash: &str) -> Result<bool> {
713        warn!("=== AUTO-RESOLVE DEBUG: Starting for commit {} ===", commit_hash);
714
715        // Check if there are actually conflicts
716        if !self.git_repo.has_conflicts()? {
717            warn!("AUTO-RESOLVE DEBUG: No conflicts detected by Git");
718            return Ok(true);
719        }
720
721        let conflicted_files = self.git_repo.get_conflicted_files()?;
722
723        if conflicted_files.is_empty() {
724            warn!("AUTO-RESOLVE DEBUG: Conflicted files list is empty");
725            return Ok(true);
726        }
727
728        warn!(
729            "AUTO-RESOLVE DEBUG: Found conflicts in {} files: {:?}",
730            conflicted_files.len(),
731            conflicted_files
732        );
733
734        // Use the new conflict analyzer for detailed analysis
735        let analysis = self
736            .conflict_analyzer
737            .analyze_conflicts(&conflicted_files, self.git_repo.path())?;
738
739        info!(
740            "๐Ÿ” Conflict analysis: {} total conflicts, {} auto-resolvable",
741            analysis.total_conflicts, analysis.auto_resolvable_count
742        );
743
744        // Display recommendations
745        for recommendation in &analysis.recommendations {
746            info!("๐Ÿ’ก {}", recommendation);
747        }
748
749        let mut resolved_count = 0;
750        let mut resolved_files = Vec::new(); // Track which files were actually resolved
751        let mut failed_files = Vec::new();
752
753        for file_analysis in &analysis.files {
754            warn!(
755                "AUTO-RESOLVE DEBUG: Processing file: {} (auto_resolvable: {}, conflicts: {})",
756                file_analysis.file_path,
757                file_analysis.auto_resolvable,
758                file_analysis.conflicts.len()
759            );
760
761            if file_analysis.auto_resolvable {
762                match self.resolve_file_conflicts_enhanced(
763                    &file_analysis.file_path,
764                    &file_analysis.conflicts,
765                ) {
766                    Ok(ConflictResolution::Resolved) => {
767                        resolved_count += 1;
768                        resolved_files.push(file_analysis.file_path.clone());
769                        warn!(
770                            "AUTO-RESOLVE DEBUG: Successfully resolved {}",
771                            file_analysis.file_path
772                        );
773                    }
774                    Ok(ConflictResolution::TooComplex) => {
775                        warn!(
776                            "AUTO-RESOLVE DEBUG: {} too complex for auto-resolution",
777                            file_analysis.file_path
778                        );
779                        failed_files.push(file_analysis.file_path.clone());
780                    }
781                    Err(e) => {
782                        warn!(
783                            "AUTO-RESOLVE DEBUG: Failed to resolve {}: {}",
784                            file_analysis.file_path, e
785                        );
786                        failed_files.push(file_analysis.file_path.clone());
787                    }
788                }
789            } else {
790                failed_files.push(file_analysis.file_path.clone());
791                warn!(
792                    "AUTO-RESOLVE DEBUG: {} requires manual resolution ({} conflicts)",
793                    file_analysis.file_path,
794                    file_analysis.conflicts.len()
795                );
796            }
797        }
798
799        if resolved_count > 0 {
800            warn!(
801                "AUTO-RESOLVE DEBUG: Resolved {}/{} files",
802                resolved_count,
803                conflicted_files.len()
804            );
805            warn!("AUTO-RESOLVE DEBUG: Resolved files: {:?}", resolved_files);
806
807            // CRITICAL: Only stage files that were successfully resolved
808            // This prevents staging files that still have conflict markers
809            let file_paths: Vec<&str> = resolved_files.iter().map(|s| s.as_str()).collect();
810            warn!("AUTO-RESOLVE DEBUG: Staging {} files", file_paths.len());
811            self.git_repo.stage_files(&file_paths)?;
812            warn!("AUTO-RESOLVE DEBUG: Files staged successfully");
813        } else {
814            warn!("AUTO-RESOLVE DEBUG: No files were resolved (resolved_count = 0)");
815        }
816
817        // Return true only if ALL conflicts were resolved
818        let all_resolved = failed_files.is_empty();
819
820        warn!(
821            "AUTO-RESOLVE DEBUG: all_resolved = {}, failed_files = {:?}",
822            all_resolved, failed_files
823        );
824
825        if !all_resolved {
826            warn!(
827                "AUTO-RESOLVE DEBUG: {} files still need manual resolution",
828                failed_files.len()
829            );
830        }
831
832        warn!("AUTO-RESOLVE DEBUG: Returning all_resolved = {}", all_resolved);
833        Ok(all_resolved)
834    }
835
836    /// Resolve conflicts using enhanced analysis
837    fn resolve_file_conflicts_enhanced(
838        &self,
839        file_path: &str,
840        conflicts: &[crate::git::ConflictRegion],
841    ) -> Result<ConflictResolution> {
842        let repo_path = self.git_repo.path();
843        let full_path = repo_path.join(file_path);
844
845        // Read the file content with conflict markers
846        let mut content = std::fs::read_to_string(&full_path)
847            .map_err(|e| CascadeError::config(format!("Failed to read file {file_path}: {e}")))?;
848
849        if conflicts.is_empty() {
850            return Ok(ConflictResolution::Resolved);
851        }
852
853        info!(
854            "Resolving {} conflicts in {} using enhanced analysis",
855            conflicts.len(),
856            file_path
857        );
858
859        let mut any_resolved = false;
860
861        // Process conflicts in reverse order to maintain string indices
862        for conflict in conflicts.iter().rev() {
863            match self.resolve_single_conflict_enhanced(conflict) {
864                Ok(Some(resolution)) => {
865                    // Replace the conflict region with the resolved content
866                    let before = &content[..conflict.start_pos];
867                    let after = &content[conflict.end_pos..];
868                    content = format!("{before}{resolution}{after}");
869                    any_resolved = true;
870                    debug!(
871                        "โœ… Resolved {} conflict at lines {}-{} in {}",
872                        format!("{:?}", conflict.conflict_type).to_lowercase(),
873                        conflict.start_line,
874                        conflict.end_line,
875                        file_path
876                    );
877                }
878                Ok(None) => {
879                    debug!(
880                        "โš ๏ธ  {} conflict at lines {}-{} in {} requires manual resolution",
881                        format!("{:?}", conflict.conflict_type).to_lowercase(),
882                        conflict.start_line,
883                        conflict.end_line,
884                        file_path
885                    );
886                    return Ok(ConflictResolution::TooComplex);
887                }
888                Err(e) => {
889                    debug!("โŒ Failed to resolve conflict in {}: {}", file_path, e);
890                    return Ok(ConflictResolution::TooComplex);
891                }
892            }
893        }
894
895        if any_resolved {
896            // Check if we resolved ALL conflicts in this file
897            let remaining_conflicts = self.parse_conflict_markers(&content)?;
898
899            if remaining_conflicts.is_empty() {
900                warn!(
901                    "AUTO-RESOLVE DEBUG: All conflicts resolved in {}, content length: {} bytes",
902                    file_path,
903                    content.len()
904                );
905
906                // CRITICAL SAFETY CHECK: Don't write empty files!
907                if content.trim().is_empty() {
908                    warn!(
909                        "AUTO-RESOLVE DEBUG: SAFETY CHECK TRIGGERED! Resolved content for {} is empty! Aborting.",
910                        file_path
911                    );
912                    return Ok(ConflictResolution::TooComplex);
913                }
914
915                // SAFETY: Create backup before writing resolved content
916                let backup_path = full_path.with_extension("cascade-backup");
917                if let Ok(original_content) = std::fs::read_to_string(&full_path) {
918                    warn!(
919                        "AUTO-RESOLVE DEBUG: Backup for {} (original: {} bytes, resolved: {} bytes)",
920                        file_path,
921                        original_content.len(),
922                        content.len()
923                    );
924                    let _ = std::fs::write(&backup_path, original_content);
925                }
926
927                // All conflicts resolved - write the file back atomically
928                crate::utils::atomic_file::write_string(&full_path, &content)?;
929
930                warn!(
931                    "AUTO-RESOLVE DEBUG: Wrote {} bytes to {}",
932                    content.len(),
933                    file_path
934                );
935                return Ok(ConflictResolution::Resolved);
936            } else {
937                info!(
938                    "โš ๏ธ  Partially resolved conflicts in {} ({} remaining)",
939                    file_path,
940                    remaining_conflicts.len()
941                );
942            }
943        }
944
945        Ok(ConflictResolution::TooComplex)
946    }
947
948    /// Helper to count whitespace consistency (lower is better)
949    #[allow(dead_code)]
950    fn count_whitespace_consistency(content: &str) -> usize {
951        let mut inconsistencies = 0;
952        let lines: Vec<&str> = content.lines().collect();
953
954        for line in &lines {
955            // Check for mixed tabs and spaces
956            if line.contains('\t') && line.contains(' ') {
957                inconsistencies += 1;
958            }
959        }
960
961        // Penalize for inconsistencies
962        lines.len().saturating_sub(inconsistencies)
963    }
964
965    /// Resolve a single conflict using enhanced analysis
966    fn resolve_single_conflict_enhanced(
967        &self,
968        conflict: &crate::git::ConflictRegion,
969    ) -> Result<Option<String>> {
970        debug!(
971            "Resolving {} conflict in {} (lines {}-{})",
972            format!("{:?}", conflict.conflict_type).to_lowercase(),
973            conflict.file_path,
974            conflict.start_line,
975            conflict.end_line
976        );
977
978        use crate::git::ConflictType;
979
980        match conflict.conflict_type {
981            ConflictType::Whitespace => {
982                // SAFETY: Only resolve if the content is truly identical except for whitespace
983                // Otherwise, it might be intentional formatting changes
984                let our_normalized = conflict
985                    .our_content
986                    .split_whitespace()
987                    .collect::<Vec<_>>()
988                    .join(" ");
989                let their_normalized = conflict
990                    .their_content
991                    .split_whitespace()
992                    .collect::<Vec<_>>()
993                    .join(" ");
994
995                if our_normalized == their_normalized {
996                    // Content is identical - in cherry-pick context, ALWAYS prefer THEIRS
997                    // CRITICAL: In cherry-pick, OURS=base branch, THEIRS=commit being applied
998                    // We must keep the commit's changes (THEIRS), not the base (OURS)
999                    // Otherwise we delete the user's code!
1000                    Ok(Some(conflict.their_content.clone()))
1001                } else {
1002                    // Content differs beyond whitespace - not safe to auto-resolve
1003                    debug!(
1004                        "Whitespace conflict has content differences - requires manual resolution"
1005                    );
1006                    Ok(None)
1007                }
1008            }
1009            ConflictType::LineEnding => {
1010                // Normalize to Unix line endings
1011                let normalized = conflict
1012                    .our_content
1013                    .replace("\r\n", "\n")
1014                    .replace('\r', "\n");
1015                Ok(Some(normalized))
1016            }
1017            ConflictType::PureAddition => {
1018                // CRITICAL: In cherry-pick, OURS=base, THEIRS=commit being applied
1019                // We must respect what the commit does (THEIRS), not what the base has (OURS)
1020
1021                if conflict.our_content.is_empty() && !conflict.their_content.is_empty() {
1022                    // Base is empty, commit adds content โ†’ keep the addition
1023                    Ok(Some(conflict.their_content.clone()))
1024                } else if conflict.their_content.is_empty() && !conflict.our_content.is_empty() {
1025                    // Base has content, commit removes it โ†’ keep it removed (empty)
1026                    Ok(Some(String::new()))
1027                } else if conflict.our_content.is_empty() && conflict.their_content.is_empty() {
1028                    // Both empty โ†’ keep empty
1029                    Ok(Some(String::new()))
1030                } else {
1031                    // Both sides have content - this could be:
1032                    // - Duplicate function definitions
1033                    // - Conflicting logic
1034                    // - Different implementations of same feature
1035                    // Too risky to auto-merge - require manual resolution
1036                    debug!(
1037                        "PureAddition conflict has content on both sides - requires manual resolution"
1038                    );
1039                    Ok(None)
1040                }
1041            }
1042            ConflictType::ImportMerge => {
1043                // SAFETY: Only merge simple single-line imports
1044                // Multi-line imports or complex cases require manual resolution
1045
1046                // Check if all imports are single-line and look like imports
1047                let our_lines: Vec<&str> = conflict.our_content.lines().collect();
1048                let their_lines: Vec<&str> = conflict.their_content.lines().collect();
1049
1050                // Verify all lines look like simple imports (heuristic check)
1051                let all_simple = our_lines.iter().chain(their_lines.iter()).all(|line| {
1052                    let trimmed = line.trim();
1053                    trimmed.starts_with("import ")
1054                        || trimmed.starts_with("from ")
1055                        || trimmed.starts_with("use ")
1056                        || trimmed.starts_with("#include")
1057                        || trimmed.is_empty()
1058                });
1059
1060                if !all_simple {
1061                    debug!("ImportMerge contains non-import lines - requires manual resolution");
1062                    return Ok(None);
1063                }
1064
1065                // Merge and deduplicate imports
1066                let mut all_imports: Vec<&str> = our_lines
1067                    .into_iter()
1068                    .chain(their_lines)
1069                    .filter(|line| !line.trim().is_empty())
1070                    .collect();
1071                all_imports.sort();
1072                all_imports.dedup();
1073                Ok(Some(all_imports.join("\n")))
1074            }
1075            ConflictType::Structural | ConflictType::ContentOverlap | ConflictType::Complex => {
1076                // These require manual resolution
1077                Ok(None)
1078            }
1079        }
1080    }
1081
1082    /// Parse conflict markers from file content
1083    fn parse_conflict_markers(&self, content: &str) -> Result<Vec<ConflictRegion>> {
1084        let lines: Vec<&str> = content.lines().collect();
1085        let mut conflicts = Vec::new();
1086        let mut i = 0;
1087
1088        while i < lines.len() {
1089            if lines[i].starts_with("<<<<<<<") {
1090                // Found start of conflict
1091                let start_line = i + 1;
1092                let mut separator_line = None;
1093                let mut end_line = None;
1094
1095                // Find the separator and end
1096                for (j, line) in lines.iter().enumerate().skip(i + 1) {
1097                    if line.starts_with("=======") {
1098                        separator_line = Some(j + 1);
1099                    } else if line.starts_with(">>>>>>>") {
1100                        end_line = Some(j + 1);
1101                        break;
1102                    }
1103                }
1104
1105                if let (Some(sep), Some(end)) = (separator_line, end_line) {
1106                    // Calculate byte positions
1107                    let start_pos = lines[..i].iter().map(|l| l.len() + 1).sum::<usize>();
1108                    let end_pos = lines[..end].iter().map(|l| l.len() + 1).sum::<usize>();
1109
1110                    let our_content = lines[(i + 1)..(sep - 1)].join("\n");
1111                    let their_content = lines[sep..(end - 1)].join("\n");
1112
1113                    conflicts.push(ConflictRegion {
1114                        start: start_pos,
1115                        end: end_pos,
1116                        start_line,
1117                        end_line: end,
1118                        our_content,
1119                        their_content,
1120                    });
1121
1122                    i = end;
1123                } else {
1124                    i += 1;
1125                }
1126            } else {
1127                i += 1;
1128            }
1129        }
1130
1131        Ok(conflicts)
1132    }
1133
1134    /// Resolve a single conflict using smart strategies
1135    fn resolve_single_conflict(
1136        &self,
1137        conflict: &ConflictRegion,
1138        file_path: &str,
1139    ) -> Result<Option<String>> {
1140        debug!(
1141            "Analyzing conflict in {} (lines {}-{})",
1142            file_path, conflict.start_line, conflict.end_line
1143        );
1144
1145        // Strategy 1: Whitespace-only differences
1146        if let Some(resolved) = self.resolve_whitespace_conflict(conflict)? {
1147            debug!("Resolved as whitespace-only conflict");
1148            return Ok(Some(resolved));
1149        }
1150
1151        // Strategy 2: Line ending differences
1152        if let Some(resolved) = self.resolve_line_ending_conflict(conflict)? {
1153            debug!("Resolved as line ending conflict");
1154            return Ok(Some(resolved));
1155        }
1156
1157        // Strategy 3: Pure addition conflicts (no overlapping changes)
1158        if let Some(resolved) = self.resolve_addition_conflict(conflict)? {
1159            debug!("Resolved as pure addition conflict");
1160            return Ok(Some(resolved));
1161        }
1162
1163        // Strategy 4: Import/dependency reordering
1164        if let Some(resolved) = self.resolve_import_conflict(conflict, file_path)? {
1165            debug!("Resolved as import reordering conflict");
1166            return Ok(Some(resolved));
1167        }
1168
1169        // No strategy could resolve this conflict
1170        Ok(None)
1171    }
1172
1173    /// Resolve conflicts that only differ by whitespace
1174    fn resolve_whitespace_conflict(&self, conflict: &ConflictRegion) -> Result<Option<String>> {
1175        let our_normalized = self.normalize_whitespace(&conflict.our_content);
1176        let their_normalized = self.normalize_whitespace(&conflict.their_content);
1177
1178        if our_normalized == their_normalized {
1179            // Only whitespace differences - prefer the version with better formatting
1180            let resolved =
1181                if conflict.our_content.trim().len() >= conflict.their_content.trim().len() {
1182                    conflict.our_content.clone()
1183                } else {
1184                    conflict.their_content.clone()
1185                };
1186
1187            return Ok(Some(resolved));
1188        }
1189
1190        Ok(None)
1191    }
1192
1193    /// Resolve conflicts that only differ by line endings
1194    fn resolve_line_ending_conflict(&self, conflict: &ConflictRegion) -> Result<Option<String>> {
1195        let our_normalized = conflict
1196            .our_content
1197            .replace("\r\n", "\n")
1198            .replace('\r', "\n");
1199        let their_normalized = conflict
1200            .their_content
1201            .replace("\r\n", "\n")
1202            .replace('\r', "\n");
1203
1204        if our_normalized == their_normalized {
1205            // Only line ending differences - prefer Unix line endings
1206            return Ok(Some(our_normalized));
1207        }
1208
1209        Ok(None)
1210    }
1211
1212    /// Resolve conflicts where both sides only add lines (no overlapping edits)
1213    fn resolve_addition_conflict(&self, conflict: &ConflictRegion) -> Result<Option<String>> {
1214        let our_lines: Vec<&str> = conflict.our_content.lines().collect();
1215        let their_lines: Vec<&str> = conflict.their_content.lines().collect();
1216
1217        // Check if one side is a subset of the other (pure addition)
1218        if our_lines.is_empty() {
1219            return Ok(Some(conflict.their_content.clone()));
1220        }
1221        if their_lines.is_empty() {
1222            return Ok(Some(conflict.our_content.clone()));
1223        }
1224
1225        // Try to merge additions intelligently
1226        let mut merged_lines = Vec::new();
1227        let mut our_idx = 0;
1228        let mut their_idx = 0;
1229
1230        while our_idx < our_lines.len() || their_idx < their_lines.len() {
1231            if our_idx >= our_lines.len() {
1232                // Only their lines left
1233                merged_lines.extend_from_slice(&their_lines[their_idx..]);
1234                break;
1235            } else if their_idx >= their_lines.len() {
1236                // Only our lines left
1237                merged_lines.extend_from_slice(&our_lines[our_idx..]);
1238                break;
1239            } else if our_lines[our_idx] == their_lines[their_idx] {
1240                // Same line - add once
1241                merged_lines.push(our_lines[our_idx]);
1242                our_idx += 1;
1243                their_idx += 1;
1244            } else {
1245                // Different lines - this might be too complex
1246                return Ok(None);
1247            }
1248        }
1249
1250        Ok(Some(merged_lines.join("\n")))
1251    }
1252
1253    /// Resolve import/dependency conflicts by sorting and merging
1254    fn resolve_import_conflict(
1255        &self,
1256        conflict: &ConflictRegion,
1257        file_path: &str,
1258    ) -> Result<Option<String>> {
1259        // Only apply to likely import sections in common file types
1260        let is_import_file = file_path.ends_with(".rs")
1261            || file_path.ends_with(".py")
1262            || file_path.ends_with(".js")
1263            || file_path.ends_with(".ts")
1264            || file_path.ends_with(".go")
1265            || file_path.ends_with(".java")
1266            || file_path.ends_with(".swift")
1267            || file_path.ends_with(".kt")
1268            || file_path.ends_with(".cs");
1269
1270        if !is_import_file {
1271            return Ok(None);
1272        }
1273
1274        let our_lines: Vec<&str> = conflict.our_content.lines().collect();
1275        let their_lines: Vec<&str> = conflict.their_content.lines().collect();
1276
1277        // Check if all lines look like imports/uses
1278        let our_imports = our_lines
1279            .iter()
1280            .all(|line| self.is_import_line(line, file_path));
1281        let their_imports = their_lines
1282            .iter()
1283            .all(|line| self.is_import_line(line, file_path));
1284
1285        if our_imports && their_imports {
1286            // Merge and sort imports
1287            let mut all_imports: Vec<&str> = our_lines.into_iter().chain(their_lines).collect();
1288            all_imports.sort();
1289            all_imports.dedup();
1290
1291            return Ok(Some(all_imports.join("\n")));
1292        }
1293
1294        Ok(None)
1295    }
1296
1297    /// Check if a line looks like an import statement
1298    fn is_import_line(&self, line: &str, file_path: &str) -> bool {
1299        let trimmed = line.trim();
1300
1301        if trimmed.is_empty() {
1302            return true; // Empty lines are OK in import sections
1303        }
1304
1305        if file_path.ends_with(".rs") {
1306            return trimmed.starts_with("use ") || trimmed.starts_with("extern crate");
1307        } else if file_path.ends_with(".py") {
1308            return trimmed.starts_with("import ") || trimmed.starts_with("from ");
1309        } else if file_path.ends_with(".js") || file_path.ends_with(".ts") {
1310            return trimmed.starts_with("import ")
1311                || trimmed.starts_with("const ")
1312                || trimmed.starts_with("require(");
1313        } else if file_path.ends_with(".go") {
1314            return trimmed.starts_with("import ") || trimmed == "import (" || trimmed == ")";
1315        } else if file_path.ends_with(".java") {
1316            return trimmed.starts_with("import ");
1317        } else if file_path.ends_with(".swift") {
1318            return trimmed.starts_with("import ") || trimmed.starts_with("@testable import ");
1319        } else if file_path.ends_with(".kt") {
1320            return trimmed.starts_with("import ") || trimmed.starts_with("@file:");
1321        } else if file_path.ends_with(".cs") {
1322            return trimmed.starts_with("using ") || trimmed.starts_with("extern alias ");
1323        }
1324
1325        false
1326    }
1327
1328    /// Normalize whitespace for comparison
1329    fn normalize_whitespace(&self, content: &str) -> String {
1330        content
1331            .lines()
1332            .map(|line| line.trim())
1333            .filter(|line| !line.is_empty())
1334            .collect::<Vec<_>>()
1335            .join("\n")
1336    }
1337
1338    /// Update a stack entry with new commit information
1339    /// NOTE: We keep the original branch name to preserve PR mapping, only update commit hash
1340    fn update_stack_entry(
1341        &mut self,
1342        stack_id: Uuid,
1343        entry_id: &Uuid,
1344        _new_branch: &str,
1345        new_commit_hash: &str,
1346    ) -> Result<()> {
1347        debug!(
1348            "Updating entry {} in stack {} with new commit {}",
1349            entry_id, stack_id, new_commit_hash
1350        );
1351
1352        // Get the stack and update the entry
1353        let stack = self
1354            .stack_manager
1355            .get_stack_mut(&stack_id)
1356            .ok_or_else(|| CascadeError::config(format!("Stack {stack_id} not found")))?;
1357
1358        // Find and update the entry
1359        if let Some(entry) = stack.entries.iter_mut().find(|e| e.id == *entry_id) {
1360            debug!(
1361                "Found entry {} - updating commit from '{}' to '{}' (keeping original branch '{}')",
1362                entry_id, entry.commit_hash, new_commit_hash, entry.branch
1363            );
1364
1365            // CRITICAL: Keep the original branch name to preserve PR mapping
1366            // Only update the commit hash to point to the new rebased commit
1367            entry.commit_hash = new_commit_hash.to_string();
1368
1369            // Note: Stack will be saved by the caller (StackManager) after rebase completes
1370
1371            debug!(
1372                "Successfully updated entry {} in stack {}",
1373                entry_id, stack_id
1374            );
1375            Ok(())
1376        } else {
1377            Err(CascadeError::config(format!(
1378                "Entry {entry_id} not found in stack {stack_id}"
1379            )))
1380        }
1381    }
1382
1383    /// Pull latest changes from remote
1384    fn pull_latest_changes(&self, branch: &str) -> Result<()> {
1385        info!("Pulling latest changes for branch {}", branch);
1386
1387        // First try to fetch (this might fail if no remote exists)
1388        match self.git_repo.fetch() {
1389            Ok(_) => {
1390                debug!("Fetch successful");
1391                // Now try to pull the specific branch
1392                match self.git_repo.pull(branch) {
1393                    Ok(_) => {
1394                        info!("Pull completed successfully for {}", branch);
1395                        Ok(())
1396                    }
1397                    Err(e) => {
1398                        warn!("Pull failed for {}: {}", branch, e);
1399                        // Don't fail the entire rebase for pull issues
1400                        Ok(())
1401                    }
1402                }
1403            }
1404            Err(e) => {
1405                warn!("Fetch failed: {}", e);
1406                // Don't fail if there's no remote configured
1407                Ok(())
1408            }
1409        }
1410    }
1411
1412    /// Check if rebase is in progress
1413    pub fn is_rebase_in_progress(&self) -> bool {
1414        // Check for git rebase state files
1415        let git_dir = self.git_repo.path().join(".git");
1416        git_dir.join("REBASE_HEAD").exists()
1417            || git_dir.join("rebase-merge").exists()
1418            || git_dir.join("rebase-apply").exists()
1419    }
1420
1421    /// Abort an in-progress rebase
1422    pub fn abort_rebase(&self) -> Result<()> {
1423        info!("Aborting rebase operation");
1424
1425        let git_dir = self.git_repo.path().join(".git");
1426
1427        // Clean up rebase state files
1428        if git_dir.join("REBASE_HEAD").exists() {
1429            std::fs::remove_file(git_dir.join("REBASE_HEAD")).map_err(|e| {
1430                CascadeError::Git(git2::Error::from_str(&format!(
1431                    "Failed to clean rebase state: {e}"
1432                )))
1433            })?;
1434        }
1435
1436        if git_dir.join("rebase-merge").exists() {
1437            std::fs::remove_dir_all(git_dir.join("rebase-merge")).map_err(|e| {
1438                CascadeError::Git(git2::Error::from_str(&format!(
1439                    "Failed to clean rebase-merge: {e}"
1440                )))
1441            })?;
1442        }
1443
1444        if git_dir.join("rebase-apply").exists() {
1445            std::fs::remove_dir_all(git_dir.join("rebase-apply")).map_err(|e| {
1446                CascadeError::Git(git2::Error::from_str(&format!(
1447                    "Failed to clean rebase-apply: {e}"
1448                )))
1449            })?;
1450        }
1451
1452        info!("Rebase aborted successfully");
1453        Ok(())
1454    }
1455
1456    /// Continue an in-progress rebase after conflict resolution
1457    pub fn continue_rebase(&self) -> Result<()> {
1458        info!("Continuing rebase operation");
1459
1460        // Check if there are still conflicts
1461        if self.git_repo.has_conflicts()? {
1462            return Err(CascadeError::branch(
1463                "Cannot continue rebase: there are unresolved conflicts. Resolve conflicts and stage files first.".to_string()
1464            ));
1465        }
1466
1467        // Stage resolved files
1468        self.git_repo.stage_conflict_resolved_files()?;
1469
1470        info!("Rebase continued successfully");
1471        Ok(())
1472    }
1473
1474    /// Check if there's an in-progress cherry-pick operation
1475    fn has_in_progress_cherry_pick(&self) -> Result<bool> {
1476        let git_dir = self.git_repo.path().join(".git");
1477        Ok(git_dir.join("CHERRY_PICK_HEAD").exists())
1478    }
1479
1480    /// Handle resuming an in-progress cherry-pick from a previous failed sync
1481    fn handle_in_progress_cherry_pick(&mut self, stack: &Stack) -> Result<RebaseResult> {
1482        use crate::cli::output::Output;
1483
1484        let git_dir = self.git_repo.path().join(".git");
1485
1486        Output::section("Resuming in-progress sync");
1487        println!();
1488        Output::info("Detected unfinished cherry-pick from previous sync");
1489        println!();
1490
1491        // Check if conflicts are resolved
1492        if self.git_repo.has_conflicts()? {
1493            let conflicted_files = self.git_repo.get_conflicted_files()?;
1494
1495            let result = RebaseResult {
1496                success: false,
1497                branch_mapping: HashMap::new(),
1498                conflicts: conflicted_files.clone(),
1499                new_commits: Vec::new(),
1500                error: Some(format!(
1501                    "Cannot continue: {} file(s) still have unresolved conflicts\n\n\
1502                    MANUAL CONFLICT RESOLUTION REQUIRED\n\
1503                    =====================================\n\n\
1504                    Conflicted files:\n{}\n\n\
1505                    Step 1: Analyze conflicts\n\
1506                    โ†’ Run: ca conflicts\n\
1507                    โ†’ Shows detailed conflict analysis\n\n\
1508                    Step 2: Resolve conflicts in your editor\n\
1509                    โ†’ Open conflicted files and edit them\n\
1510                    โ†’ Remove conflict markers (<<<<<<, ======, >>>>>>)\n\
1511                    โ†’ Keep the code you want\n\
1512                    โ†’ Save the files\n\n\
1513                    Step 3: Mark conflicts as resolved\n\
1514                    โ†’ Run: git add <resolved-files>\n\
1515                    โ†’ Or: git add -A (to stage all resolved files)\n\n\
1516                    Step 4: Complete the sync\n\
1517                    โ†’ Run: ca sync\n\
1518                    โ†’ Cascade will continue from where it left off\n\n\
1519                    Alternative: Abort and start over\n\
1520                    โ†’ Run: git cherry-pick --abort\n\
1521                    โ†’ Then: ca sync (starts fresh)",
1522                    conflicted_files.len(),
1523                    conflicted_files
1524                        .iter()
1525                        .map(|f| format!("  - {}", f))
1526                        .collect::<Vec<_>>()
1527                        .join("\n")
1528                )),
1529                summary: "Sync paused - conflicts need resolution".to_string(),
1530            };
1531
1532            return Ok(result);
1533        }
1534
1535        // Conflicts are resolved - continue the cherry-pick
1536        Output::info("Conflicts resolved, continuing cherry-pick...");
1537
1538        // Stage all resolved files
1539        self.git_repo.stage_conflict_resolved_files()?;
1540
1541        // Complete the cherry-pick by committing
1542        let cherry_pick_msg_file = git_dir.join("CHERRY_PICK_MSG");
1543        let commit_message = if cherry_pick_msg_file.exists() {
1544            std::fs::read_to_string(&cherry_pick_msg_file)
1545                .unwrap_or_else(|_| "Resolved conflicts".to_string())
1546        } else {
1547            "Resolved conflicts".to_string()
1548        };
1549
1550        match self.git_repo.commit(&commit_message) {
1551            Ok(_new_commit_id) => {
1552                Output::success("Cherry-pick completed");
1553
1554                // Clean up cherry-pick state
1555                if git_dir.join("CHERRY_PICK_HEAD").exists() {
1556                    let _ = std::fs::remove_file(git_dir.join("CHERRY_PICK_HEAD"));
1557                }
1558                if cherry_pick_msg_file.exists() {
1559                    let _ = std::fs::remove_file(&cherry_pick_msg_file);
1560                }
1561
1562                println!();
1563                Output::info("Continuing with rest of stack...");
1564                println!();
1565
1566                // Now continue with the rest of the rebase
1567                // We need to restart the full rebase since we don't track which entry we were on
1568                self.rebase_with_force_push(stack)
1569            }
1570            Err(e) => {
1571                let result = RebaseResult {
1572                    success: false,
1573                    branch_mapping: HashMap::new(),
1574                    conflicts: Vec::new(),
1575                    new_commits: Vec::new(),
1576                    error: Some(format!(
1577                        "Failed to complete cherry-pick: {}\n\n\
1578                        This usually means:\n\
1579                        - Git index is locked (another process accessing repo)\n\
1580                        - File permissions issue\n\
1581                        - Disk space issue\n\n\
1582                        Recovery:\n\
1583                        1. Check if another Git operation is running\n\
1584                        2. Run 'rm -f .git/index.lock' if stale lock exists\n\
1585                        3. Run 'git status' to check repo state\n\
1586                        4. Retry 'ca sync' after fixing the issue\n\n\
1587                        Or abort and start fresh:\n\
1588                        โ†’ Run: git cherry-pick --abort\n\
1589                        โ†’ Then: ca sync",
1590                        e
1591                    )),
1592                    summary: "Failed to complete cherry-pick".to_string(),
1593                };
1594
1595                Ok(result)
1596            }
1597        }
1598    }
1599}
1600
1601impl RebaseResult {
1602    /// Get a summary of the rebase operation
1603    pub fn get_summary(&self) -> String {
1604        if self.success {
1605            format!("โœ… {}", self.summary)
1606        } else {
1607            format!(
1608                "โŒ Rebase failed: {}",
1609                self.error.as_deref().unwrap_or("Unknown error")
1610            )
1611        }
1612    }
1613
1614    /// Check if any conflicts occurred
1615    pub fn has_conflicts(&self) -> bool {
1616        !self.conflicts.is_empty()
1617    }
1618
1619    /// Get the number of successful operations
1620    pub fn success_count(&self) -> usize {
1621        self.new_commits.len()
1622    }
1623}
1624
1625#[cfg(test)]
1626mod tests {
1627    use super::*;
1628    use std::path::PathBuf;
1629    use std::process::Command;
1630    use tempfile::TempDir;
1631
1632    #[allow(dead_code)]
1633    fn create_test_repo() -> (TempDir, PathBuf) {
1634        let temp_dir = TempDir::new().unwrap();
1635        let repo_path = temp_dir.path().to_path_buf();
1636
1637        // Initialize git repository
1638        Command::new("git")
1639            .args(["init"])
1640            .current_dir(&repo_path)
1641            .output()
1642            .unwrap();
1643        Command::new("git")
1644            .args(["config", "user.name", "Test"])
1645            .current_dir(&repo_path)
1646            .output()
1647            .unwrap();
1648        Command::new("git")
1649            .args(["config", "user.email", "test@test.com"])
1650            .current_dir(&repo_path)
1651            .output()
1652            .unwrap();
1653
1654        // Create initial commit
1655        std::fs::write(repo_path.join("README.md"), "# Test").unwrap();
1656        Command::new("git")
1657            .args(["add", "."])
1658            .current_dir(&repo_path)
1659            .output()
1660            .unwrap();
1661        Command::new("git")
1662            .args(["commit", "-m", "Initial"])
1663            .current_dir(&repo_path)
1664            .output()
1665            .unwrap();
1666
1667        (temp_dir, repo_path)
1668    }
1669
1670    #[test]
1671    fn test_conflict_region_creation() {
1672        let region = ConflictRegion {
1673            start: 0,
1674            end: 50,
1675            start_line: 1,
1676            end_line: 3,
1677            our_content: "function test() {\n    return true;\n}".to_string(),
1678            their_content: "function test() {\n  return true;\n}".to_string(),
1679        };
1680
1681        assert_eq!(region.start_line, 1);
1682        assert_eq!(region.end_line, 3);
1683        assert!(region.our_content.contains("return true"));
1684        assert!(region.their_content.contains("return true"));
1685    }
1686
1687    #[test]
1688    fn test_rebase_strategies() {
1689        assert_eq!(RebaseStrategy::ForcePush, RebaseStrategy::ForcePush);
1690        assert_eq!(RebaseStrategy::Interactive, RebaseStrategy::Interactive);
1691    }
1692
1693    #[test]
1694    fn test_rebase_options() {
1695        let options = RebaseOptions::default();
1696        assert_eq!(options.strategy, RebaseStrategy::ForcePush);
1697        assert!(!options.interactive);
1698        assert!(options.auto_resolve);
1699        assert_eq!(options.max_retries, 3);
1700    }
1701
1702    #[test]
1703    fn test_cleanup_guard_tracks_branches() {
1704        let mut guard = TempBranchCleanupGuard::new();
1705        assert!(guard.branches.is_empty());
1706
1707        guard.add_branch("test-branch-1".to_string());
1708        guard.add_branch("test-branch-2".to_string());
1709
1710        assert_eq!(guard.branches.len(), 2);
1711        assert_eq!(guard.branches[0], "test-branch-1");
1712        assert_eq!(guard.branches[1], "test-branch-2");
1713    }
1714
1715    #[test]
1716    fn test_cleanup_guard_prevents_double_cleanup() {
1717        use std::process::Command;
1718        use tempfile::TempDir;
1719
1720        // Create a temporary git repo
1721        let temp_dir = TempDir::new().unwrap();
1722        let repo_path = temp_dir.path();
1723
1724        Command::new("git")
1725            .args(["init"])
1726            .current_dir(repo_path)
1727            .output()
1728            .unwrap();
1729
1730        Command::new("git")
1731            .args(["config", "user.name", "Test"])
1732            .current_dir(repo_path)
1733            .output()
1734            .unwrap();
1735
1736        Command::new("git")
1737            .args(["config", "user.email", "test@test.com"])
1738            .current_dir(repo_path)
1739            .output()
1740            .unwrap();
1741
1742        // Create initial commit
1743        std::fs::write(repo_path.join("test.txt"), "test").unwrap();
1744        Command::new("git")
1745            .args(["add", "."])
1746            .current_dir(repo_path)
1747            .output()
1748            .unwrap();
1749        Command::new("git")
1750            .args(["commit", "-m", "initial"])
1751            .current_dir(repo_path)
1752            .output()
1753            .unwrap();
1754
1755        let git_repo = GitRepository::open(repo_path).unwrap();
1756
1757        // Create a test branch
1758        git_repo.create_branch("test-temp", None).unwrap();
1759
1760        let mut guard = TempBranchCleanupGuard::new();
1761        guard.add_branch("test-temp".to_string());
1762
1763        // First cleanup should work
1764        guard.cleanup(&git_repo);
1765        assert!(guard.cleaned);
1766
1767        // Second cleanup should be a no-op (shouldn't panic)
1768        guard.cleanup(&git_repo);
1769        assert!(guard.cleaned);
1770    }
1771
1772    #[test]
1773    fn test_rebase_result() {
1774        let result = RebaseResult {
1775            success: true,
1776            branch_mapping: std::collections::HashMap::new(),
1777            conflicts: vec!["abc123".to_string()],
1778            new_commits: vec!["def456".to_string()],
1779            error: None,
1780            summary: "Test summary".to_string(),
1781        };
1782
1783        assert!(result.success);
1784        assert!(result.has_conflicts());
1785        assert_eq!(result.success_count(), 1);
1786    }
1787
1788    #[test]
1789    fn test_import_line_detection() {
1790        let (_temp_dir, repo_path) = create_test_repo();
1791        let git_repo = crate::git::GitRepository::open(&repo_path).unwrap();
1792        let stack_manager = crate::stack::StackManager::new(&repo_path).unwrap();
1793        let options = RebaseOptions::default();
1794        let rebase_manager = RebaseManager::new(stack_manager, git_repo, options);
1795
1796        // Test Swift import detection
1797        assert!(rebase_manager.is_import_line("import Foundation", "test.swift"));
1798        assert!(rebase_manager.is_import_line("@testable import MyModule", "test.swift"));
1799        assert!(!rebase_manager.is_import_line("class MyClass {", "test.swift"));
1800
1801        // Test Kotlin import detection
1802        assert!(rebase_manager.is_import_line("import kotlin.collections.*", "test.kt"));
1803        assert!(rebase_manager.is_import_line("@file:JvmName(\"Utils\")", "test.kt"));
1804        assert!(!rebase_manager.is_import_line("fun myFunction() {", "test.kt"));
1805
1806        // Test C# import detection
1807        assert!(rebase_manager.is_import_line("using System;", "test.cs"));
1808        assert!(rebase_manager.is_import_line("using System.Collections.Generic;", "test.cs"));
1809        assert!(rebase_manager.is_import_line("extern alias GridV1;", "test.cs"));
1810        assert!(!rebase_manager.is_import_line("namespace MyNamespace {", "test.cs"));
1811
1812        // Test empty lines are allowed in import sections
1813        assert!(rebase_manager.is_import_line("", "test.swift"));
1814        assert!(rebase_manager.is_import_line("   ", "test.kt"));
1815        assert!(rebase_manager.is_import_line("", "test.cs"));
1816    }
1817}