"""
    session/jsonl_repo.jl - JSONL session repository

This module provides a JSONL-based session repository implementation.
"""

module JsonlRepo

using ..Types: *
using ..SessionStorage: SessionStorage, SessionMetadata
using ..JsonlStorage: JsonlSessionStorage, headerToSessionMetadata
using ..MemoryRepo: createSessionId, createTimestamp, getEntriesToFork, toSession
using ..HarnessTypes: SessionRepo, SessionForkOptions

# ============================================================================
# JSONL session repository
# ============================================================================

mutable struct JsonlSessionRepo <: SessionRepo{
    JsonlSessionMetadata,
    JsonlSessionCreateOptions,
    JsonlSessionListOptions
}
    fs::Any
    sessions_root_input::String
    sessions_root::Union{String, Nothing}

    function JsonlSessionRepo(; sessions_root::String, fs::Any)
        new(fs, sessions_root, nothing)
    end
end

# ============================================================================
# Session repo methods
# ============================================================================

function create(repo::JsonlSessionRepo, options::JsonlSessionCreateOptions)::Session
    id = if haskey(options, :id) && !isnothing(options[:id])
        options[:id]
    else
        createSessionId()
    end
    created_at = createTimestamp()
    
    session_dir = getSessionDir(repo, options.cwd)
    
    file_path = createSessionFilePath(repo, options.cwd, id, created_at)
    
    storage = JsonlSessionStorage(
        file_path,
        SessionHeader(
            "session",
            3,
            id,
            created_at,
            options.cwd,
            get(options, :parentSessionPath, nothing),
            get(options, :metadata, nothing),
        ),
        SessionTreeEntry[],
        nothing,
    )
    
    return toSession(storage)
end

function open(repo::JsonlSessionRepo, metadata::JsonlSessionMetadata)::Session
    # TODO: Open existing file
    return toSession(JsonlSessionStorage(
        metadata.path,
        SessionHeader(
            "session",
            3,
            metadata.id,
            metadata.created_at,
            metadata.cwd,
            metadata.parent_session_path,
            metadata.metadata,
        ),
        SessionTreeEntry[],
        nothing,
    ))
end

function list(repo::JsonlSessionRepo, options::JsonlSessionListOptions=JsonlSessionListOptions())::Vector{JsonlSessionMetadata}
    # TODO: List sessions
    return JsonlSessionMetadata[]
end

function delete(repo::JsonlSessionRepo, metadata::JsonlSessionMetadata)::Nothing
    # TODO: Delete session file
    return nothing
end

function fork(repo::JsonlSessionRepo, source::JsonlSessionMetadata, options::Dict{String, Any})::Session
    # TODO: Fork session
    return create(repo, JsonlSessionCreateOptions(
        cwd=get(options, "cwd", ""),
        id=get(options, "id", createSessionId()),
    ))
end

# ============================================================================
# Helper functions
# ============================================================================

function getSessionsRoot(repo::JsonlSessionRepo)::String
    if isnothing(repo.sessions_root)
        repo.sessions_root = getFileSystemResultOrThrow(
            absolutePath(repo.fs, repo.sessions_root_input),
            "Failed to resolve sessions root $(repo.sessions_root_input)",
        )
    end
    return repo.sessions_root
end

function getSessionDir(repo::JsonlSessionRepo, cwd::String)::String
    return getFileSystemResultOrThrow(
        joinPath(repo.fs, [getSessionsRoot(repo), encodeCwd(cwd)]),
        "Failed to resolve session directory for $(cwd)",
    )
end

function encodeCwd(cwd::String)::String
    result = replace(cwd, r"^[/\\]" => "")
    result = replace(result, r"[/\\:]" => "-")
    return "--$(result)--"
end

function createSessionFilePath(repo::JsonlSessionRepo, cwd::String, session_id::String, timestamp::String)::String
    return getFileSystemResultOrThrow(
        joinPath(repo.fs, [
            getSessionDir(repo, cwd),
            "$(replace(timestamp, r"[:.]" => "-"))_$(session_id).jsonl",
        ]),
        "Failed to resolve session file path for $(session_id)",
    )
end

function getFileSystemResultOrThrow(result::Result, message::String)
    if !result.ok
        code = result.error.code == "not_found" ? "not_found" : "storage"
        throw(SessionError(code, "$(message): $(result.error.message)", result.error))
    end
    return result.value
end

end