use super::*;
use super::issue_comments::{comment_client, comment_url, request};
use serde_json::{json, Value};

fn azure_url(base: &str, segments: &[&str]) -> Result<reqwest::Url, String> {
    let mut url = reqwest::Url::parse(&normalized_base_url(base)?).map_err(|e| e.to_string())?;
    url.path_segments_mut().map_err(|_| "Invalid Azure URL.")?.pop_if_empty().extend(segments.iter().copied());
    url.set_query(Some("api-version=7.1"));
    Ok(url)
}

fn read(response: Response, provider: &str) -> Result<Value, String> {
    if !response.status().is_success() { return Err(response_error(response, provider)); }
    response.json().map_err(|e| e.to_string())
}

#[tauri::command]
pub async fn list_azure_issue_projects(base_url: String, username: String, token: String) -> Result<Vec<String>, String> {
    tauri::async_runtime::spawn_blocking(move || {
        let client = comment_client()?;
        let mut projects = BTreeSet::new();
        let mut cursor = String::new();
        let mut seen = BTreeSet::new();
        loop {
            let mut url = azure_url(&base_url, &["_apis", "projects"])?;
            url.query_pairs_mut().append_pair("$top", "100");
            if !cursor.is_empty() { url.query_pairs_mut().append_pair("continuationToken", &cursor); }
            let response = request(&client, reqwest::Method::GET, url, "azure-devops", &username, &token)?.send().map_err(|e| e.to_string())?;
            let next = response.headers().get("x-ms-continuationtoken").and_then(|v| v.to_str().ok()).unwrap_or("").to_owned();
            let value = read(response, "azure-devops")?;
            let entries = value["value"].as_array().ok_or("Azure returned no project list.")?;
            for entry in entries {
                if let Some(name) = entry["name"].as_str().filter(|name| !name.is_empty()) { projects.insert(name.to_owned()); }
            }
            if next.is_empty() { break; }
            if !seen.insert(next.clone()) { return Err("Azure repeated a project page.".into()); }
            cursor = next;
        }
        Ok(projects.into_iter().collect())
    }).await.map_err(|e| e.to_string())?
}

#[tauri::command]
pub async fn list_azure_issue_types(base_url: String, username: String, token: String, project: String) -> Result<Vec<String>, String> {
    tauri::async_runtime::spawn_blocking(move || {
        if project.trim().is_empty() { return Err("Select an Azure project.".into()); }
        let url = azure_url(&base_url, &[&project, "_apis", "wit", "workitemtypes"])?;
        let value = read(request(&comment_client()?, reqwest::Method::GET, url, "azure-devops", &username, &token)?.send().map_err(|e| e.to_string())?, "azure-devops")?;
        let entries = value["value"].as_array().ok_or("Azure returned no work item types.")?;
        Ok(entries.iter().filter(|entry| entry["isDisabled"] != true).filter_map(|entry| entry["name"].as_str()).filter(|name| !name.is_empty()).map(str::to_owned).collect())
    }).await.map_err(|e| e.to_string())?
}

fn creation_request(provider: &str, base: &str, repository: &str, title: &str, description: &str, work_item_type: &str) -> Result<(reqwest::Url, Value), String> {
    if title.trim().is_empty() { return Err("An issue title is required.".into()); }
    if repository.trim().is_empty() { return Err("Select a repository or project.".into()); }
    if provider == "azure-devops" {
        if work_item_type.trim().is_empty() { return Err("Select a work item type.".into()); }
        let url = azure_url(base, &[repository, "_apis", "wit", "workitems", &format!("${work_item_type}")])?;
        // Azure descriptions are HTML; preserve literal user text and line breaks.
        let html = description.replace('&', "&amp;").replace('<', "&lt;").replace('>', "&gt;").replace('"', "&quot;").replace('\n', "<br>");
        let mut payload = vec![json!({"op":"add","path":"/fields/System.Title","value":title.trim()})];
        if !description.is_empty() { payload.push(json!({"op":"add","path":"/fields/System.Description","value":html})); }
        Ok((url, json!(payload)))
    } else {
        let mut url = comment_url(provider, base, repository, 1)?;
        url.path_segments_mut().map_err(|_| "Invalid issue URL.")?.pop().pop();
        let payload = if provider.starts_with("gitlab") { json!({"title":title.trim(),"description":description}) } else { json!({"title":title.trim(),"body":description}) };
        Ok((url, payload))
    }
}

#[tauri::command]
pub async fn create_integration_issue(provider: String, base_url: String, username: String, token: String, repository: String, title: String, description: String, work_item_type: String) -> Result<IntegrationIssue, String> {
    tauri::async_runtime::spawn_blocking(move || {
        let (url, payload) = creation_request(&provider, &base_url, &repository, &title, &description, &work_item_type)?;
        let client = comment_client()?;
        let mut req = request(&client, reqwest::Method::POST, url, &provider, &username, &token)?;
        if provider == "azure-devops" { req = req.header("Content-Type", "application/json-patch+json"); }
        // Never retry a creation automatically: a lost response may still mean success.
        let response = req.json(&payload).send().map_err(|e| format!("Creation was not confirmed. Check the provider before retrying: {e}"))?;
        let value = read(response, &provider)?;
        super::issues::created_issue(&value, &provider, &base_url, &repository)
    }).await.map_err(|e| e.to_string())?
}

#[cfg(test)]
mod tests {
    use super::*;
    #[test]
    fn routes_issue_creation_and_preserves_markdown() {
        for (provider, path) in [("gitea", "/sub/api/v1/repos/team/repo/issues"), ("github", "/repos/team/repo/issues"), ("gitlab", "/sub/api/v4/projects/team%2Frepo/issues"), ("gitlab-self-hosted", "/sub/api/v4/projects/team%2Frepo/issues")] {
            let (url, body) = creation_request(provider, "https://git.test/sub", "team/repo", " Title ", "**Details**", "").unwrap();
            assert_eq!(url.path(), path);
            assert_eq!(body["title"], "Title");
            assert_eq!(body[if provider.starts_with("gitlab") { "description" } else { "body" }], "**Details**");
        }
    }
    #[test]
    fn azure_uses_custom_type_and_escapes_description() {
        let (url, body) = creation_request("azure-devops", "https://dev.azure.com/org", "My Project", "Task", "<script>&\nNext", "Custom Task").unwrap();
        assert_eq!(url.path(), "/org/My%20Project/_apis/wit/workitems/$Custom%20Task");
        assert_eq!(url.query(), Some("api-version=7.1"));
        assert_eq!(body[1]["value"], "&lt;script&gt;&amp;<br>Next");
        assert!(creation_request("gitea", "https://git.test", "team/repo", "  ", "", "").is_err());
        assert!(creation_request("azure-devops", "https://dev.azure.com/org", "Project", "Task", "", "").is_err());
        assert!(creation_request("gitea", "https://git.test", "invalid", "Task", "", "").is_err());
    }
}