use opensearch::OpenSearch;
use serde::{Deserialize, Serialize};
use tracing::info;

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ArchiveDocument {
    pub event_id: String,
    pub room_id: String,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub room_name: Option<String>,
    pub sender: String,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub sender_name: Option<String>,
    pub timestamp: i64,
    pub content: String,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub reply_to: Option<String>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub thread_id: Option<String>,
    #[serde(default)]
    pub media_urls: Vec<String>,
    pub event_type: String,
    #[serde(default)]
    pub edited: bool,
    #[serde(default)]
    pub redacted: bool,
    #[serde(default, skip_serializing_if = "Vec::is_empty")]
    pub reactions: Vec<Reaction>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Reaction {
    pub sender: String,
    pub emoji: String,
    pub timestamp: i64,
}

const INDEX_MAPPING: &str = r#"{
    "settings": {
        "number_of_shards": 1,
        "number_of_replicas": 0
    },
    "mappings": {
        "properties": {
            "event_id":    { "type": "keyword" },
            "room_id":     { "type": "keyword" },
            "room_name":   { "type": "keyword" },
            "sender":      { "type": "keyword" },
            "sender_name": { "type": "keyword" },
            "timestamp":   { "type": "date", "format": "epoch_millis" },
            "content":     { "type": "text", "analyzer": "standard" },
            "reply_to":    { "type": "keyword" },
            "thread_id":   { "type": "keyword" },
            "media_urls":  { "type": "keyword" },
            "event_type":  { "type": "keyword" },
            "edited":      { "type": "boolean" },
            "redacted":    { "type": "boolean" },
            "reactions":   {
                "type": "nested",
                "properties": {
                    "sender": { "type": "keyword" },
                    "emoji":  { "type": "keyword" },
                    "timestamp": { "type": "date", "format": "epoch_millis" }
                }
            }
        }
    }
}"#;

pub fn index_mapping_json() -> &'static str {
    INDEX_MAPPING
}

pub async fn create_index_if_not_exists(client: &OpenSearch, index: &str) -> anyhow::Result<()> {
    let exists = client
        .indices()
        .exists(opensearch::indices::IndicesExistsParts::Index(&[index]))
        .send()
        .await?;

    if exists.status_code().is_success() {
        info!(index, "OpenSearch index already exists");
        // Ensure reactions field exists (added after initial schema)
        let reactions_mapping = serde_json::json!({
            "properties": {
                "reactions": {
                    "type": "nested",
                    "properties": {
                        "sender": { "type": "keyword" },
                        "emoji":  { "type": "keyword" },
                        "timestamp": { "type": "date", "format": "epoch_millis" }
                    }
                }
            }
        });
        let _ = client
            .indices()
            .put_mapping(opensearch::indices::IndicesPutMappingParts::Index(&[index]))
            .body(reactions_mapping)
            .send()
            .await;
        return Ok(());
    }

    let mapping: serde_json::Value = serde_json::from_str(INDEX_MAPPING)?;
    let response = client
        .indices()
        .create(opensearch::indices::IndicesCreateParts::Index(index))
        .body(mapping)
        .send()
        .await?;

    if !response.status_code().is_success() {
        let body = response.text().await?;
        anyhow::bail!("Failed to create index {index}: {body}");
    }

    info!(index, "Created OpenSearch index");
    Ok(())
}

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

    fn sample_doc() -> ArchiveDocument {
        ArchiveDocument {
            event_id: "$abc123:sunbeam.pt".to_string(),
            room_id: "!room:sunbeam.pt".to_string(),
            room_name: Some("general".to_string()),
            sender: "@alice:sunbeam.pt".to_string(),
            sender_name: Some("Alice".to_string()),
            timestamp: 1710000000000,
            content: "hello world".to_string(),
            reply_to: None,
            thread_id: None,
            media_urls: vec![],
            event_type: "m.room.message".to_string(),
            edited: false,
            redacted: false,
            reactions: vec![],
        }
    }

    #[test]
    fn test_serialize_full_doc() {
        let doc = sample_doc();
        let json = serde_json::to_value(&doc).unwrap();

        assert_eq!(json["event_id"], "$abc123:sunbeam.pt");
        assert_eq!(json["room_id"], "!room:sunbeam.pt");
        assert_eq!(json["room_name"], "general");
        assert_eq!(json["sender"], "@alice:sunbeam.pt");
        assert_eq!(json["sender_name"], "Alice");
        assert_eq!(json["timestamp"], 1710000000000_i64);
        assert_eq!(json["content"], "hello world");
        assert_eq!(json["event_type"], "m.room.message");
        assert_eq!(json["edited"], false);
        assert_eq!(json["redacted"], false);
        assert!(json["media_urls"].as_array().unwrap().is_empty());
    }

    #[test]
    fn test_skip_none_fields() {
        let doc = sample_doc();
        let json_str = serde_json::to_string(&doc).unwrap();
        // reply_to and thread_id are None, should be omitted
        assert!(!json_str.contains("reply_to"));
        assert!(!json_str.contains("thread_id"));
    }

    #[test]
    fn test_serialize_with_optional_fields() {
        let mut doc = sample_doc();
        doc.reply_to = Some("$parent:sunbeam.pt".to_string());
        doc.thread_id = Some("$thread:sunbeam.pt".to_string());
        doc.media_urls = vec!["mxc://sunbeam.pt/abc".to_string()];
        doc.edited = true;

        let json = serde_json::to_value(&doc).unwrap();
        assert_eq!(json["reply_to"], "$parent:sunbeam.pt");
        assert_eq!(json["thread_id"], "$thread:sunbeam.pt");
        assert_eq!(json["media_urls"][0], "mxc://sunbeam.pt/abc");
        assert_eq!(json["edited"], true);
    }

    #[test]
    fn test_deserialize_roundtrip() {
        let doc = sample_doc();
        let json_str = serde_json::to_string(&doc).unwrap();
        let deserialized: ArchiveDocument = serde_json::from_str(&json_str).unwrap();

        assert_eq!(deserialized.event_id, doc.event_id);
        assert_eq!(deserialized.room_id, doc.room_id);
        assert_eq!(deserialized.room_name, doc.room_name);
        assert_eq!(deserialized.sender, doc.sender);
        assert_eq!(deserialized.content, doc.content);
        assert_eq!(deserialized.timestamp, doc.timestamp);
        assert_eq!(deserialized.edited, doc.edited);
        assert_eq!(deserialized.redacted, doc.redacted);
    }

    #[test]
    fn test_deserialize_with_defaults() {
        // Simulate a document missing optional/default fields
        let json = r#"{
            "event_id": "$x:s",
            "room_id": "!r:s",
            "sender": "@a:s",
            "timestamp": 1000,
            "content": "test",
            "event_type": "m.room.message"
        }"#;
        let doc: ArchiveDocument = serde_json::from_str(json).unwrap();
        assert!(doc.room_name.is_none());
        assert!(doc.sender_name.is_none());
        assert!(doc.reply_to.is_none());
        assert!(doc.thread_id.is_none());
        assert!(doc.media_urls.is_empty());
        assert!(!doc.edited);
        assert!(!doc.redacted);
    }

    #[test]
    fn test_index_mapping_is_valid_json() {
        let mapping: serde_json::Value =
            serde_json::from_str(index_mapping_json()).unwrap();
        assert!(mapping["settings"]["number_of_shards"].is_number());
        assert!(mapping["mappings"]["properties"]["event_id"]["type"]
            .as_str()
            .unwrap()
            == "keyword");
        assert!(mapping["mappings"]["properties"]["content"]["type"]
            .as_str()
            .unwrap()
            == "text");
        assert!(mapping["mappings"]["properties"]["timestamp"]["type"]
            .as_str()
            .unwrap()
            == "date");
    }
}