use crate::agents::AgentStatus;
use crate::http::context::AppContext;
use crate::io::story_metadata::parse_front_matter;
use serde::Serialize;
use std::collections::HashMap;
use std::fs;
use std::path::{Path, PathBuf};

/// Agent assignment embedded in a pipeline stage item.
#[derive(Clone, Debug, Serialize)]
pub struct AgentAssignment {
    pub agent_name: String,
    pub model: Option<String>,
    pub status: String,
}

#[derive(Clone, Debug, Serialize)]
pub struct UpcomingStory {
    pub story_id: String,
    pub name: Option<String>,
    pub error: Option<String>,
    /// Active agent working on this item, if any.
    pub agent: Option<AgentAssignment>,
}

pub struct StoryValidationResult {
    pub story_id: String,
    pub valid: bool,
    pub error: Option<String>,
}

/// Full pipeline state across all stages.
#[derive(Clone, Debug, Serialize)]
pub struct PipelineState {
    pub upcoming: Vec<UpcomingStory>,
    pub current: Vec<UpcomingStory>,
    pub qa: Vec<UpcomingStory>,
    pub merge: Vec<UpcomingStory>,
}

/// Load the full pipeline state (all 4 active stages).
pub fn load_pipeline_state(ctx: &AppContext) -> Result<PipelineState, String> {
    let agent_map = build_active_agent_map(ctx);
    Ok(PipelineState {
        upcoming: load_stage_items(ctx, "1_upcoming", &HashMap::new())?,
        current: load_stage_items(ctx, "2_current", &agent_map)?,
        qa: load_stage_items(ctx, "3_qa", &agent_map)?,
        merge: load_stage_items(ctx, "4_merge", &agent_map)?,
    })
}

/// Build a map from story_id → AgentAssignment for all pending/running agents.
fn build_active_agent_map(ctx: &AppContext) -> HashMap<String, AgentAssignment> {
    let agents = match ctx.agents.list_agents() {
        Ok(a) => a,
        Err(_) => return HashMap::new(),
    };

    let config_opt = ctx
        .state
        .get_project_root()
        .ok()
        .and_then(|root| crate::config::ProjectConfig::load(&root).ok());

    let mut map = HashMap::new();
    for agent in agents {
        if !matches!(agent.status, AgentStatus::Pending | AgentStatus::Running) {
            continue;
        }
        let model = config_opt
            .as_ref()
            .and_then(|cfg| cfg.find_agent(&agent.agent_name))
            .and_then(|ac| ac.model.clone());
        map.insert(
            agent.story_id.clone(),
            AgentAssignment {
                agent_name: agent.agent_name,
                model,
                status: agent.status.to_string(),
            },
        );
    }
    map
}

/// Load work items from any pipeline stage directory.
fn load_stage_items(
    ctx: &AppContext,
    stage_dir: &str,
    agent_map: &HashMap<String, AgentAssignment>,
) -> Result<Vec<UpcomingStory>, String> {
    let root = ctx.state.get_project_root()?;
    let dir = root.join(".story_kit").join("work").join(stage_dir);

    if !dir.exists() {
        return Ok(Vec::new());
    }

    let mut stories = Vec::new();
    for entry in fs::read_dir(&dir)
        .map_err(|e| format!("Failed to read {stage_dir} directory: {e}"))?
    {
        let entry = entry.map_err(|e| format!("Failed to read {stage_dir} entry: {e}"))?;
        let path = entry.path();
        if path.extension().and_then(|ext| ext.to_str()) != Some("md") {
            continue;
        }
        let story_id = path
            .file_stem()
            .and_then(|stem| stem.to_str())
            .ok_or_else(|| "Invalid story file name.".to_string())?
            .to_string();
        let contents = fs::read_to_string(&path)
            .map_err(|e| format!("Failed to read story file {}: {e}", path.display()))?;
        let (name, error) = match parse_front_matter(&contents) {
            Ok(meta) => (meta.name, None),
            Err(e) => (None, Some(e.to_string())),
        };
        let agent = agent_map.get(&story_id).cloned();
        stories.push(UpcomingStory { story_id, name, error, agent });
    }

    stories.sort_by(|a, b| a.story_id.cmp(&b.story_id));
    Ok(stories)
}

pub fn load_upcoming_stories(ctx: &AppContext) -> Result<Vec<UpcomingStory>, String> {
    load_stage_items(ctx, "1_upcoming", &HashMap::new())
}

/// Shared create-story logic used by both the OpenApi and MCP handlers.
///
/// When `commit` is `true`, the new story file is git-added and committed to
/// the current branch immediately after creation.
pub fn create_story_file(
    root: &std::path::Path,
    name: &str,
    user_story: Option<&str>,
    acceptance_criteria: Option<&[String]>,
    commit: bool,
) -> Result<String, String> {
    let story_number = next_item_number(root)?;
    let slug = slugify_name(name);

    if slug.is_empty() {
        return Err("Name must contain at least one alphanumeric character.".to_string());
    }

    let filename = format!("{story_number}_story_{slug}.md");
    let upcoming_dir = root.join(".story_kit").join("work").join("1_upcoming");
    fs::create_dir_all(&upcoming_dir)
        .map_err(|e| format!("Failed to create upcoming directory: {e}"))?;

    let filepath = upcoming_dir.join(&filename);
    if filepath.exists() {
        return Err(format!("Story file already exists: {filename}"));
    }

    let story_id = filepath
        .file_stem()
        .and_then(|s| s.to_str())
        .unwrap_or_default()
        .to_string();

    let mut content = String::new();
    content.push_str("---\n");
    content.push_str(&format!("name: {name}\n"));
    content.push_str("test_plan: pending\n");
    content.push_str("---\n\n");
    content.push_str(&format!("# Story {story_number}: {name}\n\n"));

    content.push_str("## User Story\n\n");
    if let Some(us) = user_story {
        content.push_str(us);
        content.push('\n');
    } else {
        content.push_str("As a ..., I want ..., so that ...\n");
    }
    content.push('\n');

    content.push_str("## Acceptance Criteria\n\n");
    if let Some(criteria) = acceptance_criteria {
        for criterion in criteria {
            content.push_str(&format!("- [ ] {criterion}\n"));
        }
    } else {
        content.push_str("- [ ] TODO\n");
    }
    content.push('\n');

    content.push_str("## Out of Scope\n\n");
    content.push_str("- TBD\n");

    fs::write(&filepath, &content)
        .map_err(|e| format!("Failed to write story file: {e}"))?;

    // Watcher handles the git commit asynchronously.
    let _ = commit; // kept for API compat, ignored

    Ok(story_id)
}

// ── Bug file helpers ──────────────────────────────────────────────

/// Create a bug file in `work/1_upcoming/` with a deterministic filename and auto-commit.
///
/// Returns the bug_id (e.g. `"4_bug_login_crash"`).
pub fn create_bug_file(
    root: &Path,
    name: &str,
    description: &str,
    steps_to_reproduce: &str,
    actual_result: &str,
    expected_result: &str,
    acceptance_criteria: Option<&[String]>,
) -> Result<String, String> {
    let bug_number = next_item_number(root)?;
    let slug = slugify_name(name);

    if slug.is_empty() {
        return Err("Name must contain at least one alphanumeric character.".to_string());
    }

    let filename = format!("{bug_number}_bug_{slug}.md");
    let bugs_dir = root.join(".story_kit").join("work").join("1_upcoming");
    fs::create_dir_all(&bugs_dir)
        .map_err(|e| format!("Failed to create upcoming directory: {e}"))?;

    let filepath = bugs_dir.join(&filename);
    if filepath.exists() {
        return Err(format!("Bug file already exists: {filename}"));
    }

    let bug_id = filepath
        .file_stem()
        .and_then(|s| s.to_str())
        .unwrap_or_default()
        .to_string();

    let mut content = String::new();
    content.push_str(&format!("# Bug {bug_number}: {name}\n\n"));
    content.push_str("## Description\n\n");
    content.push_str(description);
    content.push_str("\n\n");
    content.push_str("## How to Reproduce\n\n");
    content.push_str(steps_to_reproduce);
    content.push_str("\n\n");
    content.push_str("## Actual Result\n\n");
    content.push_str(actual_result);
    content.push_str("\n\n");
    content.push_str("## Expected Result\n\n");
    content.push_str(expected_result);
    content.push_str("\n\n");
    content.push_str("## Acceptance Criteria\n\n");
    if let Some(criteria) = acceptance_criteria {
        for criterion in criteria {
            content.push_str(&format!("- [ ] {criterion}\n"));
        }
    } else {
        content.push_str("- [ ] Bug is fixed and verified\n");
    }

    fs::write(&filepath, &content).map_err(|e| format!("Failed to write bug file: {e}"))?;

    // Watcher handles the git commit asynchronously.

    Ok(bug_id)
}

/// Returns true if the item stem (filename without extension) is a bug item.
/// Bug items follow the pattern: {N}_bug_{slug}
fn is_bug_item(stem: &str) -> bool {
    // Format: {digits}_bug_{rest}
    let after_num = stem.trim_start_matches(|c: char| c.is_ascii_digit());
    after_num.starts_with("_bug_")
}

/// Extract the human-readable name from a bug file's first heading.
fn extract_bug_name(path: &Path) -> Option<String> {
    let contents = fs::read_to_string(path).ok()?;
    for line in contents.lines() {
        if let Some(rest) = line.strip_prefix("# Bug ") {
            // Format: "N: Name"
            if let Some(colon_pos) = rest.find(": ") {
                return Some(rest[colon_pos + 2..].to_string());
            }
        }
    }
    None
}

/// List all open bugs — files in `work/1_upcoming/` matching the `_bug_` naming pattern.
///
/// Returns a sorted list of `(bug_id, name)` pairs.
pub fn list_bug_files(root: &Path) -> Result<Vec<(String, String)>, String> {
    let upcoming_dir = root.join(".story_kit").join("work").join("1_upcoming");
    if !upcoming_dir.exists() {
        return Ok(Vec::new());
    }

    let mut bugs = Vec::new();
    for entry in
        fs::read_dir(&upcoming_dir).map_err(|e| format!("Failed to read upcoming directory: {e}"))?
    {
        let entry = entry.map_err(|e| format!("Failed to read entry: {e}"))?;
        let path = entry.path();

        if path.is_dir() {
            continue;
        }

        if path.extension().and_then(|ext| ext.to_str()) != Some("md") {
            continue;
        }

        let stem = path
            .file_stem()
            .and_then(|s| s.to_str())
            .ok_or_else(|| "Invalid file name.".to_string())?;

        // Only include bug items: {N}_bug_{slug}
        if !is_bug_item(stem) {
            continue;
        }

        let bug_id = stem.to_string();
        let name = extract_bug_name(&path).unwrap_or_else(|| bug_id.clone());
        bugs.push((bug_id, name));
    }

    bugs.sort_by(|a, b| a.0.cmp(&b.0));
    Ok(bugs)
}

/// Locate a work item file by searching work/2_current/ then work/1_upcoming/.
fn find_story_file(project_root: &Path, story_id: &str) -> Result<PathBuf, String> {
    let filename = format!("{story_id}.md");
    let sk = project_root.join(".story_kit").join("work");
    // Check 2_current/ first
    let current_path = sk.join("2_current").join(&filename);
    if current_path.exists() {
        return Ok(current_path);
    }
    // Fall back to 1_upcoming/
    let upcoming_path = sk.join("1_upcoming").join(&filename);
    if upcoming_path.exists() {
        return Ok(upcoming_path);
    }
    Err(format!(
        "Story '{story_id}' not found in work/2_current/ or work/1_upcoming/."
    ))
}

/// Check off the Nth unchecked acceptance criterion in a story file and auto-commit.
///
/// `criterion_index` is 0-based among unchecked (`- [ ]`) items.
pub fn check_criterion_in_file(
    project_root: &Path,
    story_id: &str,
    criterion_index: usize,
) -> Result<(), String> {
    let filepath = find_story_file(project_root, story_id)?;
    let contents = fs::read_to_string(&filepath)
        .map_err(|e| format!("Failed to read story file: {e}"))?;

    let mut unchecked_count: usize = 0;
    let mut found = false;
    let new_lines: Vec<String> = contents
        .lines()
        .map(|line| {
            let trimmed = line.trim();
            if let Some(rest) = trimmed.strip_prefix("- [ ] ") {
                if unchecked_count == criterion_index {
                    unchecked_count += 1;
                    found = true;
                    let indent_len = line.len() - trimmed.len();
                    let indent = &line[..indent_len];
                    return format!("{indent}- [x] {rest}");
                }
                unchecked_count += 1;
            }
            line.to_string()
        })
        .collect();

    if !found {
        return Err(format!(
            "Criterion index {criterion_index} out of range. Story '{story_id}' has \
             {unchecked_count} unchecked criteria (indices 0..{}).",
            unchecked_count.saturating_sub(1)
        ));
    }

    let mut new_str = new_lines.join("\n");
    if contents.ends_with('\n') {
        new_str.push('\n');
    }
    fs::write(&filepath, &new_str)
        .map_err(|e| format!("Failed to write story file: {e}"))?;

    // Watcher handles the git commit asynchronously.
    Ok(())
}

/// Update the `test_plan` front-matter field in a story file and auto-commit.
pub fn set_test_plan_in_file(
    project_root: &Path,
    story_id: &str,
    status: &str,
) -> Result<(), String> {
    let filepath = find_story_file(project_root, story_id)?;
    let contents = fs::read_to_string(&filepath)
        .map_err(|e| format!("Failed to read story file: {e}"))?;

    let mut in_front_matter = false;
    let mut front_matter_started = false;
    let mut found = false;

    let new_lines: Vec<String> = contents
        .lines()
        .map(|line| {
            if line.trim() == "---" {
                if !front_matter_started {
                    front_matter_started = true;
                    in_front_matter = true;
                } else if in_front_matter {
                    in_front_matter = false;
                }
                return line.to_string();
            }
            if in_front_matter {
                let trimmed = line.trim_start();
                if trimmed.starts_with("test_plan:") {
                    found = true;
                    return format!("test_plan: {status}");
                }
            }
            line.to_string()
        })
        .collect();

    if !found {
        return Err(format!(
            "Story '{story_id}' does not have a 'test_plan' field in its front matter."
        ));
    }

    let mut new_str = new_lines.join("\n");
    if contents.ends_with('\n') {
        new_str.push('\n');
    }
    fs::write(&filepath, &new_str)
        .map_err(|e| format!("Failed to write story file: {e}"))?;

    // Watcher handles the git commit asynchronously.
    Ok(())
}

fn slugify_name(name: &str) -> String {
    let slug: String = name
        .chars()
        .map(|c| {
            if c.is_ascii_alphanumeric() {
                c.to_ascii_lowercase()
            } else {
                '_'
            }
        })
        .collect();
    // Collapse consecutive underscores and trim edges
    let mut result = String::new();
    let mut prev_underscore = true; // start true to trim leading _
    for ch in slug.chars() {
        if ch == '_' {
            if !prev_underscore {
                result.push('_');
            }
            prev_underscore = true;
        } else {
            result.push(ch);
            prev_underscore = false;
        }
    }
    // Trim trailing underscore
    if result.ends_with('_') {
        result.pop();
    }
    result
}

/// Scan all `work/` subdirectories for the highest item number across all types (stories, bugs, spikes).
fn next_item_number(root: &std::path::Path) -> Result<u32, String> {
    let work_base = root.join(".story_kit").join("work");
    let mut max_num: u32 = 0;

    for subdir in &["1_upcoming", "2_current", "3_qa", "4_merge", "5_archived"] {
        let dir = work_base.join(subdir);
        if !dir.exists() {
            continue;
        }
        for entry in
            fs::read_dir(&dir).map_err(|e| format!("Failed to read {subdir} directory: {e}"))?
        {
            let entry = entry.map_err(|e| format!("Failed to read entry: {e}"))?;
            let name = entry.file_name();
            let name_str = name.to_string_lossy();
            // Filename format: {N}_{type}_{slug}.md — extract leading N
            let num_str: String = name_str.chars().take_while(|c| c.is_ascii_digit()).collect();
            if let Ok(n) = num_str.parse::<u32>()
                && n > max_num
            {
                max_num = n;
            }
        }
    }

    Ok(max_num + 1)
}

pub fn validate_story_dirs(
    root: &std::path::Path,
) -> Result<Vec<StoryValidationResult>, String> {
    let mut results = Vec::new();

    // Directories to validate: work/2_current/ + work/1_upcoming/
    let dirs_to_validate: Vec<PathBuf> = vec![
        root.join(".story_kit").join("work").join("2_current"),
        root.join(".story_kit").join("work").join("1_upcoming"),
    ];

    for dir in &dirs_to_validate {
        let subdir = dir.file_name().map(|n| n.to_string_lossy().into_owned()).unwrap_or_default();
        if !dir.exists() {
            continue;
        }
        for entry in
            fs::read_dir(dir).map_err(|e| format!("Failed to read {subdir} directory: {e}"))?
        {
            let entry = entry.map_err(|e| format!("Failed to read entry: {e}"))?;
            let path = entry.path();
            if path.extension().and_then(|ext| ext.to_str()) != Some("md") {
                continue;
            }
            let story_id = path
                .file_stem()
                .and_then(|stem| stem.to_str())
                .unwrap_or_default()
                .to_string();
            let contents = fs::read_to_string(&path)
                .map_err(|e| format!("Failed to read {}: {e}", path.display()))?;
            match parse_front_matter(&contents) {
                Ok(meta) => {
                    let mut errors = Vec::new();
                    if meta.name.is_none() {
                        errors.push("Missing 'name' field".to_string());
                    }
                    if meta.test_plan.is_none() {
                        errors.push("Missing 'test_plan' field".to_string());
                    }
                    if errors.is_empty() {
                        results.push(StoryValidationResult {
                            story_id,
                            valid: true,
                            error: None,
                        });
                    } else {
                        results.push(StoryValidationResult {
                            story_id,
                            valid: false,
                            error: Some(errors.join("; ")),
                        });
                    }
                }
                Err(e) => results.push(StoryValidationResult {
                    story_id,
                    valid: false,
                    error: Some(e.to_string()),
                }),
            }
        }
    }

    results.sort_by(|a, b| a.story_id.cmp(&b.story_id));
    Ok(results)
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn load_upcoming_returns_empty_when_no_dir() {
        let tmp = tempfile::tempdir().unwrap();
        let root = tmp.path().to_path_buf();
        // No .story_kit directory at all
        let ctx = crate::http::context::AppContext::new_test(root);
        let result = load_upcoming_stories(&ctx).unwrap();
        assert!(result.is_empty());
    }

    #[test]
    fn pipeline_state_includes_agent_for_running_story() {
        let tmp = tempfile::tempdir().unwrap();
        let root = tmp.path().to_path_buf();

        let current = root.join(".story_kit/work/2_current");
        fs::create_dir_all(&current).unwrap();
        fs::write(
            current.join("10_story_test.md"),
            "---\nname: Test Story\ntest_plan: approved\n---\n# Story\n",
        )
        .unwrap();

        let ctx = crate::http::context::AppContext::new_test(root);
        ctx.agents.inject_test_agent("10_story_test", "coder-1", crate::agents::AgentStatus::Running);

        let state = load_pipeline_state(&ctx).unwrap();

        assert_eq!(state.current.len(), 1);
        let item = &state.current[0];
        assert!(item.agent.is_some(), "running agent should appear on work item");
        let agent = item.agent.as_ref().unwrap();
        assert_eq!(agent.agent_name, "coder-1");
        assert_eq!(agent.status, "running");
    }

    #[test]
    fn pipeline_state_no_agent_for_completed_story() {
        let tmp = tempfile::tempdir().unwrap();
        let root = tmp.path().to_path_buf();

        let current = root.join(".story_kit/work/2_current");
        fs::create_dir_all(&current).unwrap();
        fs::write(
            current.join("11_story_done.md"),
            "---\nname: Done Story\ntest_plan: approved\n---\n# Story\n",
        )
        .unwrap();

        let ctx = crate::http::context::AppContext::new_test(root);
        ctx.agents.inject_test_agent("11_story_done", "coder-1", crate::agents::AgentStatus::Completed);

        let state = load_pipeline_state(&ctx).unwrap();

        assert_eq!(state.current.len(), 1);
        assert!(
            state.current[0].agent.is_none(),
            "completed agent should not appear on work item"
        );
    }

    #[test]
    fn pipeline_state_pending_agent_included() {
        let tmp = tempfile::tempdir().unwrap();
        let root = tmp.path().to_path_buf();

        let current = root.join(".story_kit/work/2_current");
        fs::create_dir_all(&current).unwrap();
        fs::write(
            current.join("12_story_pending.md"),
            "---\nname: Pending Story\ntest_plan: approved\n---\n# Story\n",
        )
        .unwrap();

        let ctx = crate::http::context::AppContext::new_test(root);
        ctx.agents.inject_test_agent("12_story_pending", "coder-1", crate::agents::AgentStatus::Pending);

        let state = load_pipeline_state(&ctx).unwrap();

        assert_eq!(state.current.len(), 1);
        let item = &state.current[0];
        assert!(item.agent.is_some(), "pending agent should appear on work item");
        assert_eq!(item.agent.as_ref().unwrap().status, "pending");
    }

    #[test]
    fn load_upcoming_parses_metadata() {
        let tmp = tempfile::tempdir().unwrap();
        let upcoming = tmp.path().join(".story_kit/work/1_upcoming");
        fs::create_dir_all(&upcoming).unwrap();
        fs::write(
            upcoming.join("31_story_view_upcoming.md"),
            "---\nname: View Upcoming\ntest_plan: pending\n---\n# Story\n",
        )
        .unwrap();
        fs::write(
            upcoming.join("32_story_worktree.md"),
            "---\nname: Worktree Orchestration\ntest_plan: pending\n---\n# Story\n",
        )
        .unwrap();

        let ctx = crate::http::context::AppContext::new_test(tmp.path().to_path_buf());
        let stories = load_upcoming_stories(&ctx).unwrap();
        assert_eq!(stories.len(), 2);
        assert_eq!(stories[0].story_id, "31_story_view_upcoming");
        assert_eq!(stories[0].name.as_deref(), Some("View Upcoming"));
        assert_eq!(stories[1].story_id, "32_story_worktree");
        assert_eq!(stories[1].name.as_deref(), Some("Worktree Orchestration"));
    }

    #[test]
    fn load_upcoming_skips_non_md_files() {
        let tmp = tempfile::tempdir().unwrap();
        let upcoming = tmp.path().join(".story_kit/work/1_upcoming");
        fs::create_dir_all(&upcoming).unwrap();
        fs::write(upcoming.join(".gitkeep"), "").unwrap();
        fs::write(
            upcoming.join("31_story_example.md"),
            "---\nname: A Story\ntest_plan: pending\n---\n",
        )
        .unwrap();

        let ctx = crate::http::context::AppContext::new_test(tmp.path().to_path_buf());
        let stories = load_upcoming_stories(&ctx).unwrap();
        assert_eq!(stories.len(), 1);
        assert_eq!(stories[0].story_id, "31_story_example");
    }

    #[test]
    fn validate_story_dirs_valid_files() {
        let tmp = tempfile::tempdir().unwrap();
        let current = tmp.path().join(".story_kit/work/2_current");
        let upcoming = tmp.path().join(".story_kit/work/1_upcoming");
        fs::create_dir_all(&current).unwrap();
        fs::create_dir_all(&upcoming).unwrap();
        fs::write(
            current.join("28_story_todos.md"),
            "---\nname: Show TODOs\ntest_plan: approved\n---\n# Story\n",
        )
        .unwrap();
        fs::write(
            upcoming.join("36_story_front_matter.md"),
            "---\nname: Enforce Front Matter\ntest_plan: pending\n---\n# Story\n",
        )
        .unwrap();

        let results = validate_story_dirs(tmp.path()).unwrap();
        assert_eq!(results.len(), 2);
        assert!(results.iter().all(|r| r.valid));
        assert!(results.iter().all(|r| r.error.is_none()));
    }

    #[test]
    fn validate_story_dirs_missing_front_matter() {
        let tmp = tempfile::tempdir().unwrap();
        let current = tmp.path().join(".story_kit/work/2_current");
        fs::create_dir_all(&current).unwrap();
        fs::write(current.join("28_story_todos.md"), "# No front matter\n").unwrap();

        let results = validate_story_dirs(tmp.path()).unwrap();
        assert_eq!(results.len(), 1);
        assert!(!results[0].valid);
        assert_eq!(results[0].error.as_deref(), Some("Missing front matter"));
    }

    #[test]
    fn validate_story_dirs_missing_required_fields() {
        let tmp = tempfile::tempdir().unwrap();
        let current = tmp.path().join(".story_kit/work/2_current");
        fs::create_dir_all(&current).unwrap();
        fs::write(current.join("28_story_todos.md"), "---\n---\n# Story\n").unwrap();

        let results = validate_story_dirs(tmp.path()).unwrap();
        assert_eq!(results.len(), 1);
        assert!(!results[0].valid);
        let err = results[0].error.as_deref().unwrap();
        assert!(err.contains("Missing 'name' field"));
        assert!(err.contains("Missing 'test_plan' field"));
    }

    #[test]
    fn validate_story_dirs_missing_test_plan_only() {
        let tmp = tempfile::tempdir().unwrap();
        let current = tmp.path().join(".story_kit/work/2_current");
        fs::create_dir_all(&current).unwrap();
        fs::write(
            current.join("28_story_todos.md"),
            "---\nname: A Story\n---\n# Story\n",
        )
        .unwrap();

        let results = validate_story_dirs(tmp.path()).unwrap();
        assert_eq!(results.len(), 1);
        assert!(!results[0].valid);
        let err = results[0].error.as_deref().unwrap();
        assert!(err.contains("Missing 'test_plan' field"));
        assert!(!err.contains("Missing 'name' field"));
    }

    #[test]
    fn validate_story_dirs_empty_when_no_dirs() {
        let tmp = tempfile::tempdir().unwrap();
        let results = validate_story_dirs(tmp.path()).unwrap();
        assert!(results.is_empty());
    }

    // --- slugify_name tests ---

    #[test]
    fn slugify_simple_name() {
        assert_eq!(
            slugify_name("Enforce Front Matter on All Story Files"),
            "enforce_front_matter_on_all_story_files"
        );
    }

    #[test]
    fn slugify_with_special_chars() {
        assert_eq!(slugify_name("Hello, World! (v2)"), "hello_world_v2");
    }

    #[test]
    fn slugify_leading_trailing_underscores() {
        assert_eq!(slugify_name("  spaces  "), "spaces");
    }

    #[test]
    fn slugify_consecutive_separators() {
        assert_eq!(slugify_name("a--b__c  d"), "a_b_c_d");
    }

    #[test]
    fn slugify_empty_after_strip() {
        assert_eq!(slugify_name("!!!"), "");
    }

    #[test]
    fn slugify_already_snake_case() {
        assert_eq!(slugify_name("my_story_name"), "my_story_name");
    }

    // --- next_item_number tests ---

    #[test]
    fn next_item_number_empty_dirs() {
        let tmp = tempfile::tempdir().unwrap();
        let base = tmp.path().join(".story_kit/work/1_upcoming");
        fs::create_dir_all(&base).unwrap();
        assert_eq!(next_item_number(tmp.path()).unwrap(), 1);
    }

    #[test]
    fn next_item_number_scans_all_dirs() {
        let tmp = tempfile::tempdir().unwrap();
        let upcoming = tmp.path().join(".story_kit/work/1_upcoming");
        let current = tmp.path().join(".story_kit/work/2_current");
        let archived = tmp.path().join(".story_kit/work/5_archived");
        fs::create_dir_all(&upcoming).unwrap();
        fs::create_dir_all(&current).unwrap();
        fs::create_dir_all(&archived).unwrap();
        fs::write(upcoming.join("10_story_foo.md"), "").unwrap();
        fs::write(current.join("20_story_bar.md"), "").unwrap();
        fs::write(archived.join("15_story_baz.md"), "").unwrap();
        assert_eq!(next_item_number(tmp.path()).unwrap(), 21);
    }

    #[test]
    fn next_item_number_no_work_dirs() {
        let tmp = tempfile::tempdir().unwrap();
        // No .story_kit at all
        assert_eq!(next_item_number(tmp.path()).unwrap(), 1);
    }

    // --- create_story integration tests ---

    #[test]
    fn create_story_writes_correct_content() {
        let tmp = tempfile::tempdir().unwrap();
        let upcoming = tmp.path().join(".story_kit/work/1_upcoming");
        fs::create_dir_all(&upcoming).unwrap();
        fs::write(upcoming.join("36_story_existing.md"), "").unwrap();

        let number = next_item_number(tmp.path()).unwrap();
        assert_eq!(number, 37);

        let slug = slugify_name("My New Feature");
        assert_eq!(slug, "my_new_feature");

        let filename = format!("{number}_{slug}.md");
        let filepath = upcoming.join(&filename);

        let mut content = String::new();
        content.push_str("---\n");
        content.push_str("name: My New Feature\n");
        content.push_str("test_plan: pending\n");
        content.push_str("---\n\n");
        content.push_str(&format!("# Story {number}: My New Feature\n\n"));
        content.push_str("## User Story\n\n");
        content.push_str("As a dev, I want this feature\n\n");
        content.push_str("## Acceptance Criteria\n\n");
        content.push_str("- [ ] It works\n");
        content.push_str("- [ ] It is tested\n\n");
        content.push_str("## Out of Scope\n\n");
        content.push_str("- TBD\n");

        fs::write(&filepath, &content).unwrap();

        let written = fs::read_to_string(&filepath).unwrap();
        assert!(written.starts_with("---\nname: My New Feature\ntest_plan: pending\n---"));
        assert!(written.contains("# Story 37: My New Feature"));
        assert!(written.contains("- [ ] It works"));
        assert!(written.contains("- [ ] It is tested"));
        assert!(written.contains("## Out of Scope"));
    }

    #[test]
    fn create_story_rejects_duplicate() {
        let tmp = tempfile::tempdir().unwrap();
        let upcoming = tmp.path().join(".story_kit/work/1_upcoming");
        fs::create_dir_all(&upcoming).unwrap();

        let filepath = upcoming.join("1_story_my_feature.md");
        fs::write(&filepath, "existing").unwrap();

        // Simulate the check
        assert!(filepath.exists());
    }

    // ── check_criterion_in_file tests ─────────────────────────────────────────

    fn setup_git_repo(root: &std::path::Path) {
        std::process::Command::new("git")
            .args(["init"])
            .current_dir(root)
            .output()
            .unwrap();
        std::process::Command::new("git")
            .args(["config", "user.email", "test@test.com"])
            .current_dir(root)
            .output()
            .unwrap();
        std::process::Command::new("git")
            .args(["config", "user.name", "Test"])
            .current_dir(root)
            .output()
            .unwrap();
        std::process::Command::new("git")
            .args(["commit", "--allow-empty", "-m", "init"])
            .current_dir(root)
            .output()
            .unwrap();
    }

    fn story_with_criteria(n: usize) -> String {
        let mut s = "---\nname: Test Story\ntest_plan: pending\n---\n\n## Acceptance Criteria\n\n".to_string();
        for i in 0..n {
            s.push_str(&format!("- [ ] Criterion {i}\n"));
        }
        s
    }

    #[test]
    fn check_criterion_marks_first_unchecked() {
        let tmp = tempfile::tempdir().unwrap();
        setup_git_repo(tmp.path());
        let current = tmp.path().join(".story_kit/work/2_current");
        fs::create_dir_all(&current).unwrap();
        let filepath = current.join("1_test.md");
        fs::write(&filepath, story_with_criteria(3)).unwrap();
        std::process::Command::new("git")
            .args(["add", "."])
            .current_dir(tmp.path())
            .output()
            .unwrap();
        std::process::Command::new("git")
            .args(["commit", "-m", "add story"])
            .current_dir(tmp.path())
            .output()
            .unwrap();

        check_criterion_in_file(tmp.path(), "1_test", 0).unwrap();

        let contents = fs::read_to_string(&filepath).unwrap();
        assert!(contents.contains("- [x] Criterion 0"), "first should be checked");
        assert!(contents.contains("- [ ] Criterion 1"), "second should stay unchecked");
        assert!(contents.contains("- [ ] Criterion 2"), "third should stay unchecked");
    }

    #[test]
    fn check_criterion_marks_second_unchecked() {
        let tmp = tempfile::tempdir().unwrap();
        setup_git_repo(tmp.path());
        let current = tmp.path().join(".story_kit/work/2_current");
        fs::create_dir_all(&current).unwrap();
        let filepath = current.join("2_test.md");
        fs::write(&filepath, story_with_criteria(3)).unwrap();
        std::process::Command::new("git")
            .args(["add", "."])
            .current_dir(tmp.path())
            .output()
            .unwrap();
        std::process::Command::new("git")
            .args(["commit", "-m", "add story"])
            .current_dir(tmp.path())
            .output()
            .unwrap();

        check_criterion_in_file(tmp.path(), "2_test", 1).unwrap();

        let contents = fs::read_to_string(&filepath).unwrap();
        assert!(contents.contains("- [ ] Criterion 0"), "first should stay unchecked");
        assert!(contents.contains("- [x] Criterion 1"), "second should be checked");
        assert!(contents.contains("- [ ] Criterion 2"), "third should stay unchecked");
    }

    #[test]
    fn check_criterion_out_of_range_returns_error() {
        let tmp = tempfile::tempdir().unwrap();
        setup_git_repo(tmp.path());
        let current = tmp.path().join(".story_kit/work/2_current");
        fs::create_dir_all(&current).unwrap();
        let filepath = current.join("3_test.md");
        fs::write(&filepath, story_with_criteria(2)).unwrap();
        std::process::Command::new("git")
            .args(["add", "."])
            .current_dir(tmp.path())
            .output()
            .unwrap();
        std::process::Command::new("git")
            .args(["commit", "-m", "add story"])
            .current_dir(tmp.path())
            .output()
            .unwrap();

        let result = check_criterion_in_file(tmp.path(), "3_test", 5);
        assert!(result.is_err(), "should fail for out-of-range index");
        assert!(result.unwrap_err().contains("out of range"));
    }

    // ── set_test_plan_in_file tests ───────────────────────────────────────────

    #[test]
    fn set_test_plan_updates_pending_to_approved() {
        let tmp = tempfile::tempdir().unwrap();
        setup_git_repo(tmp.path());
        let current = tmp.path().join(".story_kit/work/2_current");
        fs::create_dir_all(&current).unwrap();
        let filepath = current.join("4_test.md");
        fs::write(
            &filepath,
            "---\nname: Test Story\ntest_plan: pending\n---\n\n## Body\n",
        )
        .unwrap();
        std::process::Command::new("git")
            .args(["add", "."])
            .current_dir(tmp.path())
            .output()
            .unwrap();
        std::process::Command::new("git")
            .args(["commit", "-m", "add story"])
            .current_dir(tmp.path())
            .output()
            .unwrap();

        set_test_plan_in_file(tmp.path(), "4_test", "approved").unwrap();

        let contents = fs::read_to_string(&filepath).unwrap();
        assert!(contents.contains("test_plan: approved"), "should be updated to approved");
        assert!(!contents.contains("test_plan: pending"), "old value should be replaced");
    }

    #[test]
    fn set_test_plan_missing_field_returns_error() {
        let tmp = tempfile::tempdir().unwrap();
        setup_git_repo(tmp.path());
        let current = tmp.path().join(".story_kit/work/2_current");
        fs::create_dir_all(&current).unwrap();
        let filepath = current.join("5_test.md");
        fs::write(
            &filepath,
            "---\nname: Test Story\n---\n\n## Body\n",
        )
        .unwrap();
        std::process::Command::new("git")
            .args(["add", "."])
            .current_dir(tmp.path())
            .output()
            .unwrap();
        std::process::Command::new("git")
            .args(["commit", "-m", "add story"])
            .current_dir(tmp.path())
            .output()
            .unwrap();

        let result = set_test_plan_in_file(tmp.path(), "5_test", "approved");
        assert!(result.is_err(), "should fail if test_plan field is missing");
        assert!(result.unwrap_err().contains("test_plan"));
    }

    #[test]
    fn find_story_file_searches_current_then_upcoming() {
        let tmp = tempfile::tempdir().unwrap();
        let current = tmp.path().join(".story_kit/work/2_current");
        let upcoming = tmp.path().join(".story_kit/work/1_upcoming");
        fs::create_dir_all(&current).unwrap();
        fs::create_dir_all(&upcoming).unwrap();

        // Only in upcoming
        fs::write(upcoming.join("6_test.md"), "").unwrap();
        let found = find_story_file(tmp.path(), "6_test").unwrap();
        assert!(found.ends_with("1_upcoming/6_test.md") || found.ends_with("1_upcoming\\6_test.md"));

        // Also in current — current should win
        fs::write(current.join("6_test.md"), "").unwrap();
        let found = find_story_file(tmp.path(), "6_test").unwrap();
        assert!(found.ends_with("2_current/6_test.md") || found.ends_with("2_current\\6_test.md"));
    }

    #[test]
    fn find_story_file_returns_error_when_not_found() {
        let tmp = tempfile::tempdir().unwrap();
        let result = find_story_file(tmp.path(), "99_missing");
        assert!(result.is_err());
        assert!(result.unwrap_err().contains("not found"));
    }

    // ── Bug file helper tests ──────────────────────────────────────────────────

    #[test]
    fn next_item_number_starts_at_1_when_empty_bugs() {
        let tmp = tempfile::tempdir().unwrap();
        assert_eq!(next_item_number(tmp.path()).unwrap(), 1);
    }

    #[test]
    fn next_item_number_increments_from_existing_bugs() {
        let tmp = tempfile::tempdir().unwrap();
        let upcoming = tmp.path().join(".story_kit/work/1_upcoming");
        fs::create_dir_all(&upcoming).unwrap();
        fs::write(upcoming.join("1_bug_crash.md"), "").unwrap();
        fs::write(upcoming.join("3_bug_another.md"), "").unwrap();
        assert_eq!(next_item_number(tmp.path()).unwrap(), 4);
    }

    #[test]
    fn next_item_number_scans_archived_too() {
        let tmp = tempfile::tempdir().unwrap();
        let upcoming = tmp.path().join(".story_kit/work/1_upcoming");
        let archived = tmp.path().join(".story_kit/work/5_archived");
        fs::create_dir_all(&upcoming).unwrap();
        fs::create_dir_all(&archived).unwrap();
        fs::write(archived.join("5_bug_old.md"), "").unwrap();
        assert_eq!(next_item_number(tmp.path()).unwrap(), 6);
    }

    #[test]
    fn list_bug_files_empty_when_no_bugs_dir() {
        let tmp = tempfile::tempdir().unwrap();
        let result = list_bug_files(tmp.path()).unwrap();
        assert!(result.is_empty());
    }

    #[test]
    fn list_bug_files_excludes_archive_subdir() {
        let tmp = tempfile::tempdir().unwrap();
        let upcoming_dir = tmp.path().join(".story_kit/work/1_upcoming");
        let archived_dir = tmp.path().join(".story_kit/work/5_archived");
        fs::create_dir_all(&upcoming_dir).unwrap();
        fs::create_dir_all(&archived_dir).unwrap();
        fs::write(upcoming_dir.join("1_bug_open.md"), "# Bug 1: Open Bug\n").unwrap();
        fs::write(archived_dir.join("2_bug_closed.md"), "# Bug 2: Closed Bug\n").unwrap();

        let result = list_bug_files(tmp.path()).unwrap();
        assert_eq!(result.len(), 1);
        assert_eq!(result[0].0, "1_bug_open");
        assert_eq!(result[0].1, "Open Bug");
    }

    #[test]
    fn list_bug_files_sorted_by_id() {
        let tmp = tempfile::tempdir().unwrap();
        let upcoming_dir = tmp.path().join(".story_kit/work/1_upcoming");
        fs::create_dir_all(&upcoming_dir).unwrap();
        fs::write(upcoming_dir.join("3_bug_third.md"), "# Bug 3: Third\n").unwrap();
        fs::write(upcoming_dir.join("1_bug_first.md"), "# Bug 1: First\n").unwrap();
        fs::write(upcoming_dir.join("2_bug_second.md"), "# Bug 2: Second\n").unwrap();

        let result = list_bug_files(tmp.path()).unwrap();
        assert_eq!(result.len(), 3);
        assert_eq!(result[0].0, "1_bug_first");
        assert_eq!(result[1].0, "2_bug_second");
        assert_eq!(result[2].0, "3_bug_third");
    }

    #[test]
    fn extract_bug_name_parses_heading() {
        let tmp = tempfile::tempdir().unwrap();
        let path = tmp.path().join("bug-1-crash.md");
        fs::write(&path, "# Bug 1: Login page crashes\n\n## Description\n").unwrap();
        let name = extract_bug_name(&path).unwrap();
        assert_eq!(name, "Login page crashes");
    }

    #[test]
    fn create_bug_file_writes_correct_content() {
        let tmp = tempfile::tempdir().unwrap();
        setup_git_repo(tmp.path());

        let bug_id = create_bug_file(
            tmp.path(),
            "Login Crash",
            "The login page crashes on submit.",
            "1. Go to /login\n2. Click submit",
            "Page crashes with 500 error",
            "Login succeeds",
            Some(&["Login form submits without error".to_string()]),
        )
        .unwrap();

        assert_eq!(bug_id, "1_bug_login_crash");

        let filepath = tmp
            .path()
            .join(".story_kit/work/1_upcoming/1_bug_login_crash.md");
        assert!(filepath.exists());
        let contents = fs::read_to_string(&filepath).unwrap();
        assert!(contents.contains("# Bug 1: Login Crash"));
        assert!(contents.contains("## Description"));
        assert!(contents.contains("The login page crashes on submit."));
        assert!(contents.contains("## How to Reproduce"));
        assert!(contents.contains("1. Go to /login"));
        assert!(contents.contains("## Actual Result"));
        assert!(contents.contains("Page crashes with 500 error"));
        assert!(contents.contains("## Expected Result"));
        assert!(contents.contains("Login succeeds"));
        assert!(contents.contains("## Acceptance Criteria"));
        assert!(contents.contains("- [ ] Login form submits without error"));
    }

    #[test]
    fn create_bug_file_rejects_empty_name() {
        let tmp = tempfile::tempdir().unwrap();
        let result = create_bug_file(tmp.path(), "!!!", "desc", "steps", "actual", "expected", None);
        assert!(result.is_err());
        assert!(result.unwrap_err().contains("alphanumeric"));
    }

    #[test]
    fn create_bug_file_uses_default_acceptance_criterion() {
        let tmp = tempfile::tempdir().unwrap();
        setup_git_repo(tmp.path());

        create_bug_file(
            tmp.path(),
            "Some Bug",
            "desc",
            "steps",
            "actual",
            "expected",
            None,
        )
        .unwrap();

        let filepath = tmp.path().join(".story_kit/work/1_upcoming/1_bug_some_bug.md");
        let contents = fs::read_to_string(&filepath).unwrap();
        assert!(contents.contains("- [ ] Bug is fixed and verified"));
    }
}